Fix clang-tidy check readability-implicit-bool-cast.

96 files changed, 1040 insertions, 988 deletions

diff --git a/src/gui/widgets/attrs/attrdisplay.cpp b/src/gui/widgets/attrs/attrdisplay.cpp
index 503444e7f..3b91fef9d 100644
--- a/src/gui/widgets/attrs/attrdisplay.cpp
+++ b/src/gui/widgets/attrs/attrdisplay.cpp
@@ -60,7 +60,7 @@ std::string AttrDisplay::update()
     const int base = PlayerInfo::getStatBase(mId);
     const int bonus = PlayerInfo::getStatMod(mId);
     std::string value = toString(base + bonus);
-    if (bonus)
+    if (bonus != 0)
         value.append(strprintf("=%d%+d", base, bonus));
     mValue->setCaption(value);
     return mName;
diff --git a/src/gui/widgets/attrs/attrdisplay.h b/src/gui/widgets/attrs/attrdisplay.h
index c4f23339f..1641bac9f 100644
--- a/src/gui/widgets/attrs/attrdisplay.h
+++ b/src/gui/widgets/attrs/attrdisplay.h
@@ -54,7 +54,7 @@ class AttrDisplay notfinal : public Container
 
         std::string getValue() const
         {
-            if (!mValue)
+            if (mValue == nullptr)
                 return "-";
             else
                 return mValue->getCaption();
diff --git a/src/gui/widgets/avatarlistbox.cpp b/src/gui/widgets/avatarlistbox.cpp
index c81798e29..383efb397 100644
--- a/src/gui/widgets/avatarlistbox.cpp
+++ b/src/gui/widgets/avatarlistbox.cpp
@@ -56,7 +56,7 @@ Image *AvatarListBox::offlineIcon = nullptr;
 AvatarListBox::AvatarListBox(const Widget2 *const widget,
                              AvatarListModel *const model) :
     ListBox(widget, model, "avatarlistbox.xml"),
-    mImagePadding(mSkin ? mSkin->getOption("imagePadding") : 0),
+    mImagePadding(mSkin != nullptr ? mSkin->getOption("imagePadding") : 0),
     mShowGender(config.getBoolValue("showgender")),
     mShowLevel(config.getBoolValue("showlevel"))
 {
@@ -86,12 +86,12 @@ AvatarListBox::~AvatarListBox()
 
     if (instances == 0)
     {
-        if (onlineIcon)
+        if (onlineIcon != nullptr)
         {
             onlineIcon->decRef();
             onlineIcon = nullptr;
         }
-        if (offlineIcon)
+        if (offlineIcon != nullptr)
         {
             offlineIcon->decRef();
             offlineIcon = nullptr;
@@ -102,14 +102,14 @@ AvatarListBox::~AvatarListBox()
 void AvatarListBox::draw(Graphics *const graphics)
 {
     BLOCK_START("AvatarListBox::draw")
-    if (!mListModel || !localPlayer)
+    if ((mListModel == nullptr) || (localPlayer == nullptr))
     {
         BLOCK_END("AvatarListBox::draw")
         return;
     }
 
     const Widget *const parent = mParent;
-    if (!parent)
+    if (parent == nullptr)
         return;
 
     AvatarListModel *const model = static_cast<AvatarListModel *>(
@@ -129,7 +129,7 @@ void AvatarListBox::draw(Graphics *const graphics)
          ++i, y += fontHeight)
     {
         const Avatar *const a = model->getAvatarAt(i);
-        if (!a)
+        if (a == nullptr)
             continue;
 
         const MapItemType::Type type = static_cast<MapItemType::Type>(
@@ -139,7 +139,7 @@ void AvatarListBox::draw(Graphics *const graphics)
             // Draw online status
             const Image *const icon = a->getOnline()
                 ? onlineIcon : offlineIcon;
-            if (icon)
+            if (icon != nullptr)
             {
                 graphics->calcTileCollection(&vertexes, icon,
                     mImagePadding, y + mPadding);
@@ -155,7 +155,7 @@ void AvatarListBox::draw(Graphics *const graphics)
          ++i, y += fontHeight)
     {
         const Avatar *const a = model->getAvatarAt(i);
-        if (!a)
+        if (a == nullptr)
             continue;
 
         const MapItemType::Type type = static_cast<MapItemType::Type>(
@@ -175,7 +175,7 @@ void AvatarListBox::draw(Graphics *const graphics)
                                  a->getHp(), a->getMaxHp());
             }
             const bool isPoison = a->getPoison();
-            if (a->getMaxHp())
+            if (a->getMaxHp() != 0)
             {
                 const ProgressColorIdT themeColor = (isPoison
                     ? ProgressColorId::PROG_HP_POISON
@@ -347,14 +347,14 @@ void AvatarListBox::draw(Graphics *const graphics)
 void AvatarListBox::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("AvatarListBox::draw")
-    if (!mListModel || !localPlayer)
+    if ((mListModel == nullptr) || (localPlayer == nullptr))
     {
         BLOCK_END("AvatarListBox::draw")
         return;
     }
 
     const Widget *const parent = mParent;
-    if (!parent)
+    if (parent == nullptr)
         return;
 
     AvatarListModel *const model = static_cast<AvatarListModel *>(
@@ -373,7 +373,7 @@ void AvatarListBox::safeDraw(Graphics *const graphics)
          ++i, y += fontHeight)
     {
         const Avatar *const a = model->getAvatarAt(i);
-        if (!a)
+        if (a == nullptr)
             continue;
 
         const MapItemType::Type type = static_cast<MapItemType::Type>(
@@ -383,7 +383,7 @@ void AvatarListBox::safeDraw(Graphics *const graphics)
             // Draw online status
             const Image *const icon = a->getOnline()
                 ? onlineIcon : offlineIcon;
-            if (icon)
+            if (icon != nullptr)
                 graphics->drawImage(icon, mImagePadding, y + mPadding);
         }
     }
@@ -393,7 +393,7 @@ void AvatarListBox::safeDraw(Graphics *const graphics)
          ++i, y += fontHeight)
     {
         const Avatar *const a = model->getAvatarAt(i);
-        if (!a)
+        if (a == nullptr)
             continue;
 
         const MapItemType::Type type = static_cast<MapItemType::Type>(
@@ -413,7 +413,7 @@ void AvatarListBox::safeDraw(Graphics *const graphics)
                                  a->getHp(), a->getMaxHp());
             }
             const bool isPoison = a->getPoison();
-            if (a->getMaxHp())
+            if (a->getMaxHp() != 0)
             {
                 const ProgressColorIdT themeColor = (isPoison
                     ? ProgressColorId::PROG_HP_POISON
@@ -584,15 +584,19 @@ void AvatarListBox::safeDraw(Graphics *const graphics)
 
 void AvatarListBox::mousePressed(MouseEvent &event)
 {
-    if (!actorManager || !localPlayer || !popupManager)
+    if (actorManager == nullptr ||
+        localPlayer == nullptr ||
+        popupManager == nullptr)
+    {
         return;
+    }
 
     const int height = getFont()->getHeight();
-    if (!height)
+    if (height == 0)
         return;
 
     const int y = (event.getY() - mPadding) / height;
-    if (!mListModel || y > mListModel->getNumberOfElements())
+    if ((mListModel == nullptr) || y > mListModel->getNumberOfElements())
         return;
 
     setSelected(y);
@@ -600,10 +604,10 @@ void AvatarListBox::mousePressed(MouseEvent &event)
     const int selected = getSelected();
     AvatarListModel *const model = static_cast<AvatarListModel *>(
         mListModel);
-    if (!model)
+    if (model == nullptr)
         return;
     const Avatar *ava = model->getAvatarAt(selected);
-    if (!ava)
+    if (ava == nullptr)
         return;
 
     const MapItemType::Type type = static_cast<MapItemType::Type>(
@@ -618,7 +622,7 @@ void AvatarListBox::mousePressed(MouseEvent &event)
         {
             const Being *const being = actorManager->findBeingByName(
                 ava->getName(), ActorType::Player);
-            if (being)
+            if (being != nullptr)
                 actorManager->heal(being);
         }
         else
@@ -634,11 +638,11 @@ void AvatarListBox::mousePressed(MouseEvent &event)
             case MapItemType::EMPTY:
             {
                 const Avatar *const avatar = model->getAvatarAt(selected);
-                if (avatar)
+                if (avatar != nullptr)
                 {
                     const Being *const being = actorManager->findBeingByName(
                         avatar->getName(), ActorType::Player);
-                    if (being)
+                    if (being != nullptr)
                     {
                         popupMenu->showPopup(viewport->mMouseX,
                             viewport->mMouseY,
@@ -698,7 +702,7 @@ void AvatarListBox::mousePressed(MouseEvent &event)
             {
                 const Map *const map = viewport->getMap();
                 ava = model->getAvatarAt(selected);
-                if (map && ava)
+                if ((map != nullptr) && (ava != nullptr))
                 {
                     MapItem *const mapItem = map->findPortalXY(
                         ava->getX(), ava->getY());
@@ -712,12 +716,12 @@ void AvatarListBox::mousePressed(MouseEvent &event)
     }
     else if (eventButton == MouseButton::MIDDLE)
     {
-        if (type == MapItemType::EMPTY && chatWindow)
+        if (type == MapItemType::EMPTY && (chatWindow != nullptr))
         {
             const std::string &name = model->getAvatarAt(selected)->getName();
             const WhisperTab *const tab = chatWindow->addWhisperTab(
                 name, name, true);
-            if (tab)
+            if (tab != nullptr)
                 chatWindow->saveState();
         }
     }
diff --git a/src/gui/widgets/basiccontainer.cpp b/src/gui/widgets/basiccontainer.cpp
index 68f440fcf..771ba83f4 100644
--- a/src/gui/widgets/basiccontainer.cpp
+++ b/src/gui/widgets/basiccontainer.cpp
@@ -234,7 +234,7 @@ void BasicContainer::setFocusHandler(FocusHandler *restrict2 const
 {
     Widget::setFocusHandler(focusHandler);
 
-    if (mInternalFocusHandler)
+    if (mInternalFocusHandler != nullptr)
         return;
 
     FOR_EACH (WidgetListConstIterator, iter, mWidgets)
@@ -243,13 +243,13 @@ void BasicContainer::setFocusHandler(FocusHandler *restrict2 const
 
 void BasicContainer::add(Widget *const widget) restrict2
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     mWidgets.push_back(widget);
     if (widget->isAllowLogic())
         mLogicWidgets.push_back(widget);
 
-    if (!mInternalFocusHandler)
+    if (mInternalFocusHandler == nullptr)
         widget->setFocusHandler(getFocusHandler());
     else
         widget->setFocusHandler(mInternalFocusHandler);
@@ -260,7 +260,7 @@ void BasicContainer::add(Widget *const widget) restrict2
 
 void BasicContainer::remove(Widget *const restrict widget) restrict2
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     FOR_EACH (WidgetListIterator, iter, mWidgets)
     {
@@ -391,7 +391,7 @@ void BasicContainer::logicChildren() restrict2
 void BasicContainer::showWidgetPart(Widget *restrict const widget,
                                     const Rect &restrict area) restrict2
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     const Rect widgetArea = getChildrenArea();
@@ -417,7 +417,7 @@ void BasicContainer::setInternalFocusHandler(FocusHandler *const restrict
 {
     Widget::setInternalFocusHandler(focusHandler);
 
-    FocusHandler *const restrict handler = mInternalFocusHandler ?
+    FocusHandler *const restrict handler = mInternalFocusHandler != nullptr ?
         mInternalFocusHandler : getFocusHandler();
     FOR_EACH (WidgetListConstIterator, iter, mWidgets)
     {
diff --git a/src/gui/widgets/basiccontainer2.cpp b/src/gui/widgets/basiccontainer2.cpp
index c89cf1962..ad143010d 100644
--- a/src/gui/widgets/basiccontainer2.cpp
+++ b/src/gui/widgets/basiccontainer2.cpp
@@ -121,7 +121,7 @@ void BasicContainer2::addXY(Widget *const widget,
                             const int x,
                             const int y)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     widget->setPosition(x, y);
     BasicContainer::add(widget);
diff --git a/src/gui/widgets/browserbox.cpp b/src/gui/widgets/browserbox.cpp
index 0c35b63d4..22a6cec9d 100644
--- a/src/gui/widgets/browserbox.cpp
+++ b/src/gui/widgets/browserbox.cpp
@@ -123,7 +123,7 @@ BrowserBox::BrowserBox(const Widget2 *const widget,
 
     mBackgroundColor = getThemeColor(ThemeColorId::BACKGROUND);
 
-    if (theme)
+    if (theme != nullptr)
         mSkin = theme->load(skin, "browserbox.xml");
     if (mInstances == 0)
     {
@@ -132,15 +132,15 @@ BrowserBox::BrowserBox(const Widget2 *const widget,
     }
     mInstances ++;
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mPadding = mSkin->getPadding();
         mNewLinePadding = CAST_U32(
             mSkin->getOption("newLinePadding", 15));
         mItemPadding = mSkin->getOption("itemPadding");
-        if (mSkin->getOption("highlightBackground"))
+        if (mSkin->getOption("highlightBackground") != 0)
             mHighlightMode |= LinkHighlightMode::BACKGROUND;
-        if (mSkin->getOption("highlightUnderline"))
+        if (mSkin->getOption("highlightUnderline") != 0)
             mHighlightMode |= LinkHighlightMode::UNDERLINE;
     }
 
@@ -161,10 +161,10 @@ BrowserBox::BrowserBox(const Widget2 *const widget,
 
 BrowserBox::~BrowserBox()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
-    if (theme)
+    if (theme != nullptr)
     {
         theme->unload(mSkin);
         mSkin = nullptr;
@@ -173,7 +173,7 @@ BrowserBox::~BrowserBox()
     mInstances --;
     if (mInstances == 0)
     {
-        if (mEmotes)
+        if (mEmotes != nullptr)
         {
             mEmotes->decRef();
             mEmotes = nullptr;
@@ -231,7 +231,7 @@ void BrowserBox::addRow(const std::string &row, const bool atTop)
             {
                 bLink.caption = BrowserBoxTools::replaceLinkCommands(
                     bLink.link);
-                if (translator)
+                if (translator != nullptr)
                     bLink.caption = translator->getStr(bLink.caption);
             }
 
@@ -295,7 +295,7 @@ void BrowserBox::addRow(const std::string &row, const bool atTop)
             int cnt = mTextRowLinksCount.front();
             mTextRowLinksCount.pop_front();
 
-            while (cnt && !mLinks.empty())
+            while ((cnt != 0) && !mLinks.empty())
             {
                 mLinks.erase(mLinks.begin());
                 cnt --;
@@ -413,7 +413,7 @@ void BrowserBox::clearRows()
 
 void BrowserBox::mousePressed(MouseEvent &event)
 {
-    if (!mLinkHandler)
+    if (mLinkHandler == nullptr)
         return;
 
     const LinkIterator i = std::find_if(mLinks.begin(), mLinks.end(),
@@ -462,7 +462,7 @@ void BrowserBox::draw(Graphics *const graphics)
     if (mSelectedLink >= 0 &&
         mSelectedLink < CAST_S32(mLinks.size()))
     {
-        if ((mHighlightMode & LinkHighlightMode::BACKGROUND))
+        if ((mHighlightMode & LinkHighlightMode::BACKGROUND) != 0u)
         {
             BrowserLink &link = mLinks[CAST_SIZE(mSelectedLink)];
             graphics->setColor(mHighlightColor);
@@ -473,7 +473,7 @@ void BrowserBox::draw(Graphics *const graphics)
                 link.y2 - link.y1));
         }
 
-        if ((mHighlightMode & LinkHighlightMode::UNDERLINE))
+        if ((mHighlightMode & LinkHighlightMode::UNDERLINE) != 0u)
         {
             BrowserLink &link = mLinks[CAST_SIZE(mSelectedLink)];
             graphics->setColor(mHyperLinkColor);
@@ -494,7 +494,7 @@ void BrowserBox::draw(Graphics *const graphics)
             continue;
         if (part.mY > yEnd)
             break;
-        if (!part.mType)
+        if (part.mType == 0u)
         {
             if (part.mBold)
             {
@@ -513,7 +513,7 @@ void BrowserBox::draw(Graphics *const graphics)
                     part.mX, part.mY);
             }
         }
-        else if (part.mImage)
+        else if (part.mImage != nullptr)
         {
             graphics->drawImage(part.mImage, part.mX, part.mY);
         }
@@ -580,7 +580,7 @@ int BrowserBox::calcHeight()
             if (sz > 2 && str.substr(sz - 1) == "~")
                 str = str.substr(0, sz - 1);
             Image *const img = Loader::getImage(str);
-            if (img)
+            if (img != nullptr)
             {
                 img->incRef();
                 mLineParts.push_back(LinePart(CAST_S32(x),
@@ -757,14 +757,14 @@ int BrowserBox::calcHeight()
                         const int cid = row.at(start + 2) - '0';
                         if (cid >= 0)
                         {
-                            if (mEmotes)
+                            if (mEmotes != nullptr)
                             {
                                 const size_t sz = mEmotes->size();
                                 if (CAST_SIZE(cid) < sz)
                                 {
                                     Image *const img = mEmotes->get(
                                         CAST_SIZE(cid));
-                                    if (img)
+                                    if (img != nullptr)
                                     {
                                         mLineParts.push_back(LinePart(
                                             CAST_S32(x),
@@ -890,7 +890,7 @@ int BrowserBox::calcHeight()
 void BrowserBox::updateHeight()
 {
     if (mAlwaysUpdate || mUpdateTime != cur_time
-        || mTextRows.size() < 3 || !mUpdateTime)
+        || mTextRows.size() < 3 || (mUpdateTime == 0))
     {
         mWidth = mDimension.width;
         mHeight = calcHeight();
@@ -958,7 +958,7 @@ void BrowserBox::moveSelectionDown()
 
 void BrowserBox::selectSelection()
 {
-    if (!mLinkHandler ||
+    if ((mLinkHandler == nullptr) ||
         mSelectedLink < 0 ||
         mSelectedLink >= static_cast<signed int>(mLinks.size()))
     {
diff --git a/src/gui/widgets/button.cpp b/src/gui/widgets/button.cpp
index f24d5c9a0..3509b927c 100644
--- a/src/gui/widgets/button.cpp
+++ b/src/gui/widgets/button.cpp
@@ -183,7 +183,7 @@ Button::Button(const Widget2 *const widget,
     adjustSize();
     setActionEventId(actionEventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 }
 
@@ -234,7 +234,7 @@ Button::Button(const Widget2 *const widget,
     adjustSize();
     setActionEventId(actionEventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 }
 
@@ -284,7 +284,7 @@ Button::Button(const Widget2 *const widget,
     adjustSize();
     setActionEventId(actionEventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 }
 
@@ -334,7 +334,7 @@ Button::Button(const Widget2 *const widget,
     adjustSize();
     setActionEventId(actionEventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 }
 
@@ -351,12 +351,12 @@ void Button::init()
 
     if (mInstances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             for (int mode = 0; mode < BUTTON_COUNT; mode ++)
             {
                 Skin *const skin = theme->load(data[mode], "button.xml");
-                if (skin)
+                if (skin != nullptr)
                 {
                     button[mode] = skin;
                     mSpacing[mode] = skin->getOption("spacing");
@@ -372,26 +372,26 @@ void Button::init()
 
 Button::~Button()
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->removeWidgetListener(this);
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     mInstances--;
 
-    if (mInstances == 0 && theme)
+    if (mInstances == 0 && (theme != nullptr))
     {
         for (int mode = 0; mode < BUTTON_COUNT; mode ++)
             theme->unload(button[mode]);
     }
     delete2(mVertexes2);
-    if (mImageSet)
+    if (mImageSet != nullptr)
     {
         mImageSet->decRef();
         mImageSet = nullptr;
     }
-    if (mImages)
+    if (mImages != nullptr)
     {
         for (int f = 0; f < BUTTON_COUNT; f ++)
             mImages[f] = nullptr;
@@ -403,7 +403,7 @@ Button::~Button()
 
 void Button::loadImage(const std::string &imageName)
 {
-    if (mImageSet)
+    if (mImageSet != nullptr)
     {
         mImageSet->decRef();
         mImageSet = nullptr;
@@ -416,21 +416,21 @@ void Button::loadImage(const std::string &imageName)
 
 void Button::loadImageSet(const std::string &imageName)
 {
-    if (mImageSet)
+    if (mImageSet != nullptr)
     {
         mImageSet->decRef();
         mImageSet = nullptr;
     }
     mImageSet = Theme::getImageSetFromTheme(imageName,
         mImageWidth, mImageHeight);
-    if (!mImageSet)
+    if (mImageSet == nullptr)
         return;
     mImages = new Image*[BUTTON_COUNT];
     mImages[0] = nullptr;
     for (size_t f = 0; f < BUTTON_COUNT; f ++)
     {
         Image *const img = mImageSet->get(f);
-        if (img)
+        if (img != nullptr)
             mImages[f] = img;
         else
             mImages[f] = mImages[0];
@@ -450,11 +450,11 @@ void Button::updateAlpha()
             for (int a = 0; a < 9; a ++)
             {
                 Skin *const skin = button[mode];
-                if (skin)
+                if (skin != nullptr)
                 {
                     const ImageRect &rect = skin->getBorder();
                     Image *const image = rect.grid[a];
-                    if (image)
+                    if (image != nullptr)
                         image->setAlpha(mAlpha);
                 }
             }
@@ -477,7 +477,7 @@ void Button::draw(Graphics *const graphics)
         mode = BUTTON_STANDARD;
 
     const Skin *const skin = button[mode];
-    if (!skin)
+    if (skin == nullptr)
     {
         BLOCK_END("Button::draw")
         return;
@@ -526,7 +526,7 @@ void Button::draw(Graphics *const graphics)
     const int height = rect.height;
     Font *const font = getFont();
     int textY = height / 2 - font->getHeight() / 2;
-    if (mImages)
+    if (mImages != nullptr)
         imageY = height / 2 - mImageHeight / 2;
 
 // need move calculation from draw!!!
@@ -536,7 +536,7 @@ void Button::draw(Graphics *const graphics)
         default:
         case Graphics::LEFT:
         {
-            if (mImages)
+            if (mImages != nullptr)
             {
                 imageX = padding;
                 textX = padding + mImageWidth + spacing;
@@ -550,7 +550,7 @@ void Button::draw(Graphics *const graphics)
         case Graphics::CENTER:
         {
             const int width1 = font->getWidth(mCaption);
-            if (mImages)
+            if (mImages != nullptr)
             {
                 const int w = width1 + mImageWidth + spacing;
                 imageX = (width - w) / 2;
@@ -581,7 +581,7 @@ void Button::draw(Graphics *const graphics)
             width, height,
             skin->getBorder());
 
-        if (mImages)
+        if (mImages != nullptr)
         {
             if (isPressed())
             {
@@ -635,7 +635,7 @@ void Button::draw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, textX, textY);
 
     BLOCK_END("Button::draw")
@@ -656,7 +656,7 @@ void Button::safeDraw(Graphics *const graphics)
         mode = BUTTON_STANDARD;
 
     const Skin *const skin = button[mode];
-    if (!skin)
+    if (skin == nullptr)
     {
         BLOCK_END("Button::safeDraw")
         return;
@@ -681,7 +681,7 @@ void Button::safeDraw(Graphics *const graphics)
     const int height = rect.height;
     Font *const font = getFont();
     int textY = height / 2 - font->getHeight() / 2;
-    if (mImages)
+    if (mImages != nullptr)
         imageY = height / 2 - mImageHeight / 2;
 
 // need move calculation from draw!!!
@@ -691,7 +691,7 @@ void Button::safeDraw(Graphics *const graphics)
         default:
         case Graphics::LEFT:
         {
-            if (mImages)
+            if (mImages != nullptr)
             {
                 imageX = padding;
                 textX = padding + mImageWidth + spacing;
@@ -705,7 +705,7 @@ void Button::safeDraw(Graphics *const graphics)
         case Graphics::CENTER:
         {
             const int width1 = font->getWidth(mCaption);
-            if (mImages)
+            if (mImages != nullptr)
             {
                 const int w = width1 + mImageWidth + spacing;
                 imageX = (width - w) / 2;
@@ -728,7 +728,7 @@ void Button::safeDraw(Graphics *const graphics)
 
     graphics->drawImageRect(0, 0, width, height, skin->getBorder());
 
-    if (mImages)
+    if (mImages != nullptr)
     {
         if (isPressed())
             graphics->drawImage(mImages[mode], imageX + 1, imageY + 1);
@@ -771,7 +771,7 @@ void Button::safeDraw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, textX, textY);
 
     BLOCK_END("Button::safeDraw")
@@ -822,15 +822,15 @@ void Button::adjustSize()
 {
     const Font *const font = getFont();
     const Skin *const skin = button[BUTTON_STANDARD];
-    if (!skin)
+    if (skin == nullptr)
         return;
     const int padding = skin->getPadding();
 
-    if (mImages)
+    if (mImages != nullptr)
     {
         const int spacing = mSpacing[BUTTON_STANDARD];
         const int width = font->getWidth(mCaption);
-        if (width)
+        if (width != 0)
             setWidth(width + mImageWidth + spacing + 2 * padding);
         else
             setWidth(mImageWidth + 2 * padding);
@@ -916,14 +916,14 @@ void Button::mouseDragged(MouseEvent& event)
 
 void Button::setParent(Widget *widget)
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->addWidgetListener(this);
     Widget::setParent(widget);
 }
 
 void Button::setWindow(Widget *const widget)
 {
-    if (!widget && mWindow)
+    if ((widget == nullptr) && (mWindow != nullptr))
     {
         mWindow->removeWidgetListener(this);
         mWindow = nullptr;
diff --git a/src/gui/widgets/characterdisplay.cpp b/src/gui/widgets/characterdisplay.cpp
index 696b8c2bf..c3b5ea064 100644
--- a/src/gui/widgets/characterdisplay.cpp
+++ b/src/gui/widgets/characterdisplay.cpp
@@ -85,7 +85,7 @@ void CharacterDisplay::setCharacter(Net::Character *const character)
         return;
 
     mCharacter = character;
-    mPlayerBox->setPlayer(character ? character->dummy : nullptr);
+    mPlayerBox->setPlayer(character != nullptr ? character->dummy : nullptr);
     update();
 }
 
@@ -99,7 +99,7 @@ void CharacterDisplay::setActive(const bool active A_UNUSED)
 
 void CharacterDisplay::update()
 {
-    if (mCharacter)
+    if (mCharacter != nullptr)
         mName->setCaption(mCharacter->dummy->getName());
     else
         mName->setCaption("");
@@ -111,20 +111,24 @@ void CharacterDisplay::update()
 
 void CharacterDisplay::widgetHidden(const Event &event A_UNUSED)
 {
-    if (textPopup)
+    if (textPopup != nullptr)
         textPopup->setVisible(Visible_false);
 }
 
 void CharacterDisplay::mouseExited(MouseEvent &event A_UNUSED)
 {
-    if (textPopup)
+    if (textPopup != nullptr)
         textPopup->setVisible(Visible_false);
 }
 
 void CharacterDisplay::mouseMoved(MouseEvent &event A_UNUSED)
 {
-    if (!gui || !textPopup || !mCharacter)
+    if (gui == nullptr ||
+        textPopup == nullptr ||
+        mCharacter == nullptr)
+    {
         return;
+    }
 
     int mouseX = 0;
     int mouseY = 0;
diff --git a/src/gui/widgets/characterviewnormal.cpp b/src/gui/widgets/characterviewnormal.cpp
index c4bf0d5ef..c92ad7477 100644
--- a/src/gui/widgets/characterviewnormal.cpp
+++ b/src/gui/widgets/characterviewnormal.cpp
@@ -34,7 +34,7 @@ CharacterViewNormal::CharacterViewNormal(CharSelectDialog *const widget,
     mCharacterEntries(entries)
 {
     addKeyListener(widget);
-    if (entries)
+    if (entries != nullptr)
     {
         FOR_EACHP (std::vector<CharacterDisplay*>::iterator,
                     it, entries)
@@ -47,7 +47,7 @@ CharacterViewNormal::CharacterViewNormal(CharSelectDialog *const widget,
         if (mSelected >= 0 && mSelected < CAST_S32(sz))
         {
             CharacterDisplay *const display = (*mCharacterEntries)[mSelected];
-            if (display)
+            if (display != nullptr)
                 display->setSelect(false);
         }
         if (sz > 0)
diff --git a/src/gui/widgets/characterviewsmall.cpp b/src/gui/widgets/characterviewsmall.cpp
index dbb04064f..a861e5033 100644
--- a/src/gui/widgets/characterviewsmall.cpp
+++ b/src/gui/widgets/characterviewsmall.cpp
@@ -40,7 +40,7 @@ CharacterViewSmall::CharacterViewSmall(CharSelectDialog *const widget,
     mCharacterEntries(entries)
 {
     addKeyListener(widget);
-    if (entries)
+    if (entries != nullptr)
     {
         FOR_EACHP (std::vector<CharacterDisplay*>::iterator,
                    it, entries)
@@ -81,7 +81,7 @@ void CharacterViewSmall::show(const int i)
     const int sz = CAST_S32(mCharacterEntries->size());
     if (sz <= 0)
         return;
-    if (mSelectedEntry)
+    if (mSelectedEntry != nullptr)
         mSelectedEntry->setVisible(Visible_false);
     if (i >= sz)
         mSelected = 0;
diff --git a/src/gui/widgets/chatinput.h b/src/gui/widgets/chatinput.h
index 2a6a23a80..92c7dc341 100644
--- a/src/gui/widgets/chatinput.h
+++ b/src/gui/widgets/chatinput.h
@@ -60,7 +60,7 @@ class ChatInput final : public TextField
             if (mFocusGaining || !config.getBoolValue("protectChatFocus"))
             {
                 processVisible(Visible_false);
-                if (chatWindow)
+                if (chatWindow != nullptr)
                     chatWindow->updateVisibility();
                 mFocusGaining = false;
                 return;
@@ -72,7 +72,7 @@ class ChatInput final : public TextField
 
         void processVisible(const Visible n)
         {
-            if (!mWindow || isVisible() == (n == Visible_true))
+            if (mWindow == nullptr || isVisible() == (n == Visible_true))
                 return;
 
             if (n == Visible_false)
@@ -83,7 +83,7 @@ class ChatInput final : public TextField
             {
                 mWindow->adjustTabSize();
             }
-            if (emoteWindow)
+            if (emoteWindow != nullptr)
             {
                 emoteWindow->hide();
             }
diff --git a/src/gui/widgets/checkbox.cpp b/src/gui/widgets/checkbox.cpp
index 03da61a7b..ab1227b08 100644
--- a/src/gui/widgets/checkbox.cpp
+++ b/src/gui/widgets/checkbox.cpp
@@ -115,7 +115,7 @@ CheckBox::CheckBox(const Widget2 *const widget,
     mForegroundColor2 = getThemeColor(ThemeColorId::CHECKBOX_OUTLINE);
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             mSkin = theme->load("checkbox.xml", "");
             updateAlpha();
@@ -127,17 +127,17 @@ CheckBox::CheckBox(const Widget2 *const widget,
     if (!eventId.empty())
         setActionEventId(eventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 
     mForegroundColor = getThemeColor(ThemeColorId::CHECKBOX);
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mPadding = mSkin->getPadding();
         mImagePadding = mSkin->getOption("imagePadding");
         mImageSize = mSkin->getOption("imageSize");
         mSpacing = mSkin->getOption("spacing");
-        mDrawBox = mSkin->getOption("drawBox", 1);
+        mDrawBox = (mSkin->getOption("drawBox", 1) != 0);
         mTextX = mPadding + mImageSize + mSpacing;
     }
     adjustSize();
@@ -145,17 +145,17 @@ CheckBox::CheckBox(const Widget2 *const widget,
 
 CheckBox::~CheckBox()
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->removeWidgetListener(this);
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     instances--;
 
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
     }
 }
@@ -179,7 +179,7 @@ void CheckBox::draw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, mTextX, mPadding);
 
     BLOCK_END("CheckBox::draw")
@@ -198,13 +198,13 @@ void CheckBox::updateAlpha()
     if (mAlpha != alpha)
     {
         mAlpha = alpha;
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             const ImageRect &rect = mSkin->getBorder();
             for (int a = 0; a < 6; a ++)
             {
                 Image *const image = rect.grid[a];
-                if (image)
+                if (image != nullptr)
                     image->setAlpha(mAlpha);
             }
         }
@@ -213,7 +213,7 @@ void CheckBox::updateAlpha()
 
 void CheckBox::drawBox(Graphics *const graphics)
 {
-    if (!mSkin || !mDrawBox)
+    if ((mSkin == nullptr) || !mDrawBox)
         return;
 
     const ImageRect &rect = mSkin->getBorder();
@@ -247,7 +247,7 @@ void CheckBox::drawBox(Graphics *const graphics)
 
     updateAlpha();
 
-    if (box)
+    if (box != nullptr)
     {
         graphics->drawImage(box,
             mImagePadding,
@@ -313,7 +313,7 @@ void CheckBox::setCaption(const std::string& caption)
 
 void CheckBox::setParent(Widget *widget)
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->addWidgetListener(this);
     Widget::setParent(widget);
 }
@@ -326,7 +326,7 @@ void CheckBox::widgetHidden(const Event &event A_UNUSED)
 
 void CheckBox::setWindow(Widget *const widget)
 {
-    if (!widget && mWindow)
+    if ((widget == nullptr) && (mWindow != nullptr))
     {
         mWindow->removeWidgetListener(this);
         mWindow = nullptr;
diff --git a/src/gui/widgets/colorpage.cpp b/src/gui/widgets/colorpage.cpp
index f29540c0f..fa3099c2c 100644
--- a/src/gui/widgets/colorpage.cpp
+++ b/src/gui/widgets/colorpage.cpp
@@ -35,11 +35,11 @@ ColorPage::ColorPage(const Widget2 *const widget,
                      const std::string &skin) :
     ListBox(widget, listModel, skin)
 {
-    mItemPadding = mSkin ? mSkin->getOption("itemPadding") : 1;
+    mItemPadding = mSkin != nullptr ? mSkin->getOption("itemPadding") : 1;
     const Font *const font = getFont();
     mRowHeight = CAST_U32(font->getHeight() +
         2 * mItemPadding);
-    if (mListModel)
+    if (mListModel != nullptr)
     {
         setHeight(CAST_S32(getRowHeight()) *
             mListModel->getNumberOfElements()
@@ -114,7 +114,7 @@ void ColorPage::resetAction()
 void ColorPage::adjustSize()
 {
     BLOCK_START("ColorPage::adjustSize")
-    if (mListModel)
+    if (mListModel != nullptr)
     {
         setHeight(CAST_S32(getRowHeight()) *
             mListModel->getNumberOfElements() +
diff --git a/src/gui/widgets/container.cpp b/src/gui/widgets/container.cpp
index e6f8ad4f4..2da444728 100644
--- a/src/gui/widgets/container.cpp
+++ b/src/gui/widgets/container.cpp
@@ -34,7 +34,7 @@ Container::Container(const Widget2 *const widget) :
 
 Container::~Container()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
     removeControls();
 }
diff --git a/src/gui/widgets/containerplacer.cpp b/src/gui/widgets/containerplacer.cpp
index 8db3a0e25..634a87fcd 100644
--- a/src/gui/widgets/containerplacer.cpp
+++ b/src/gui/widgets/containerplacer.cpp
@@ -29,15 +29,16 @@
 
 ContainerPlacer ContainerPlacer::at(const int x, const int y)
 {
-    return ContainerPlacer(mContainer, mCell ? &mCell->at(x, y) : nullptr);
+    return ContainerPlacer(mContainer,
+        mCell != nullptr ? &mCell->at(x, y) : nullptr);
 }
 
 LayoutCell &ContainerPlacer::operator()
     (const int x, const int y, Widget *const wg, const int w, const int h)
 {
-    if (mContainer)
+    if (mContainer != nullptr)
         mContainer->add(wg);
-    if (mCell)
+    if (mCell != nullptr)
         return mCell->place(wg, x, y, w, h);
     return LayoutCell::emptyCell;
 }
diff --git a/src/gui/widgets/desktop.cpp b/src/gui/widgets/desktop.cpp
index 83d5bd58e..43248ebe8 100644
--- a/src/gui/widgets/desktop.cpp
+++ b/src/gui/widgets/desktop.cpp
@@ -64,11 +64,11 @@ Desktop::Desktop(const Widget2 *const widget) :
 
     Wallpaper::loadWallpapers();
 
-    if (theme)
+    if (theme != nullptr)
         mSkin = theme->load("desktop.xml", "");
 
-    if (mSkin)
-        mShowBackground = mSkin->getOption("showBackground");
+    if (mSkin != nullptr)
+        mShowBackground = (mSkin->getOption("showBackground") != 0);
 
     const std::string appName = branding.getValue("appName", std::string());
     if (appName.empty())
@@ -87,18 +87,18 @@ Desktop::Desktop(const Widget2 *const widget) :
 
 Desktop::~Desktop()
 {
-    if (mWallpaper)
+    if (mWallpaper != nullptr)
     {
         mWallpaper->decRef();
         mWallpaper = nullptr;
     }
-    if (theme)
+    if (theme != nullptr)
         theme->unload(mSkin);
 }
 
 void Desktop::postInit()
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         addXY(mVersionLabel,
             mSkin->getOption("versionX", 25),
@@ -130,7 +130,7 @@ void Desktop::draw(Graphics *const graphics)
     const Rect &rect = mDimension;
     const int width = rect.width;
     const int height = rect.height;
-    if (mWallpaper)
+    if (mWallpaper != nullptr)
     {
         const int wallpWidth = mWallpaper->getWidth();
         const int wallpHeight = mWallpaper->getHeight();
@@ -178,9 +178,9 @@ void Desktop::setBestFittingWallpaper()
 
     Image *const nWallPaper = Theme::getImageFromTheme(wallpaperName);
 
-    if (nWallPaper)
+    if (nWallPaper != nullptr)
     {
-        if (mWallpaper)
+        if (mWallpaper != nullptr)
         {
             ResourceManager::decRefDelete(mWallpaper);
             mWallpaper = nullptr;
@@ -198,7 +198,7 @@ void Desktop::setBestFittingWallpaper()
             Image *const newRsclWlPpr = Loader::getRescaled(
                 nWallPaper, width, height);
 
-            if (newRsclWlPpr)
+            if (newRsclWlPpr != nullptr)
             {
                 ResourceManager::decRefDelete(nWallPaper);
                 // We replace the resource in the resource manager
diff --git a/src/gui/widgets/dropdown.cpp b/src/gui/widgets/dropdown.cpp
index eb848f4d6..cb9eef73d 100644
--- a/src/gui/widgets/dropdown.cpp
+++ b/src/gui/widgets/dropdown.cpp
@@ -84,20 +84,20 @@ DropDown::DropDown(const Widget2 *const widget,
     mPopup->setHeight(100);
 
     // Initialize graphics
-    if (instances == 0 && theme)
+    if (instances == 0 && (theme != nullptr))
     {
         // Load the background skin
         for (int i = 0; i < 2; i ++)
         {
             Skin *const skin = theme->load(dropdownFiles[i], "dropdown.xml");
-            if (skin)
+            if (skin != nullptr)
             {
-                if (!i)
+                if (i == 0)
                     mSkin = skin;
                 const ImageRect &rect = skin->getBorder();
                 for (int f = 0; f < 2; f ++)
                 {
-                    if (rect.grid[f])
+                    if (rect.grid[f] != nullptr)
                     {
                         rect.grid[f]->incRef();
                         buttons[f][i] = rect.grid[f];
@@ -108,7 +108,7 @@ DropDown::DropDown(const Widget2 *const widget,
                         buttons[f][i] = nullptr;
                     }
                 }
-                if (i)
+                if (i != 0)
                     theme->unload(skin);
             }
             else
@@ -144,12 +144,12 @@ DropDown::DropDown(const Widget2 *const widget,
     if (!eventId.empty())
         setActionEventId(eventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 
     mPopup->adjustSize();
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mSpacing = mSkin->getOption("spacing");
         mFrameSize = CAST_U32(mSkin->getOption("frameSize"));
@@ -161,7 +161,7 @@ DropDown::DropDown(const Widget2 *const widget,
 
 DropDown::~DropDown()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     instances--;
@@ -171,11 +171,11 @@ DropDown::~DropDown()
         {
             for (int i = 0; i < 2; i ++)
             {
-                if (buttons[f][i])
+                if (buttons[f][i] != nullptr)
                     buttons[f][i]->decRef();
             }
         }
-        if (theme)
+        if (theme != nullptr)
         {
             theme->unload(mSkin);
             Theme::unloadRect(skinRect);
@@ -192,18 +192,18 @@ void DropDown::updateAlpha()
     {
         mAlpha = alpha;
 
-        if (buttons[0][0])
+        if (buttons[0][0] != nullptr)
             buttons[0][0]->setAlpha(mAlpha);
-        if (buttons[0][1])
+        if (buttons[0][1] != nullptr)
             buttons[0][1]->setAlpha(mAlpha);
-        if (buttons[1][0])
+        if (buttons[1][0] != nullptr)
             buttons[1][0]->setAlpha(mAlpha);
-        if (buttons[1][1])
+        if (buttons[1][1] != nullptr)
             buttons[1][1]->setAlpha(mAlpha);
 
         for (int a = 0; a < 9; a++)
         {
-            if (skinRect.grid[a])
+            if (skinRect.grid[a] != nullptr)
                 skinRect.grid[a]->setAlpha(mAlpha);
         }
     }
@@ -227,7 +227,7 @@ void DropDown::draw(Graphics *const graphics)
     mShadowColor.a = alpha;
 
     ListModel *const model = mPopup->getListModel();
-    if (model && mPopup->getSelected() >= 0)
+    if ((model != nullptr) && mPopup->getSelected() >= 0)
     {
         Font *const font = getFont();
         if (mExtended)
@@ -236,7 +236,7 @@ void DropDown::draw(Graphics *const graphics)
             ExtendedListModel *const model2
                 = static_cast<ExtendedListModel *>(model);
             const Image *const image = model2->getImageAt(sel);
-            if (!image)
+            if (image == nullptr)
             {
                 font->drawString(graphics,
                     mForegroundColor,
@@ -320,7 +320,7 @@ void DropDown::drawButton(Graphics *const graphics)
     const int height = mDroppedDown ? mFoldedUpHeight : mDimension.height;
 
     Image *image = buttons[mDroppedDown][mPushed];
-    if (image)
+    if (image != nullptr)
     {
         graphics->drawImage(image,
             mDimension.width - image->getWidth() - mImagePadding,
@@ -356,7 +356,7 @@ void DropDown::keyPressed(KeyEvent& event)
             break;
 
         case InputAction::GUI_END:
-            if (mPopup->getListModel())
+            if (mPopup->getListModel() != nullptr)
             {
                 setSelected(mPopup->getListModel()->
                     getNumberOfElements() - 1);
@@ -441,7 +441,7 @@ void DropDown::mouseWheelMovedDown(MouseEvent& event)
 void DropDown::setSelectedString(const std::string &str)
 {
     ListModel *const listModel = mPopup->getListModel();
-    if (!listModel)
+    if (listModel == nullptr)
         return;
 
     for (int f = 0; f < listModel->getNumberOfElements(); f ++)
@@ -457,7 +457,7 @@ void DropDown::setSelectedString(const std::string &str)
 std::string DropDown::getSelectedString() const
 {
     ListModel *const listModel = mPopup->getListModel();
-    if (!listModel)
+    if (listModel == nullptr)
         return "";
 
     return listModel->getElementAt(getSelected());
@@ -472,7 +472,7 @@ void DropDown::dropDown()
 {
     if (!mDroppedDown)
     {
-        if (!mParent)
+        if (mParent == nullptr)
             return;
         mDroppedDown = true;
         mFoldedUpHeight = getHeight();
diff --git a/src/gui/widgets/emotepage.cpp b/src/gui/widgets/emotepage.cpp
index 771813d1b..459e386a4 100644
--- a/src/gui/widgets/emotepage.cpp
+++ b/src/gui/widgets/emotepage.cpp
@@ -54,7 +54,7 @@ EmotePage::EmotePage(const Widget2 *const widget) :
 
 EmotePage::~EmotePage()
 {
-    if (mEmotes)
+    if (mEmotes != nullptr)
     {
         mEmotes->decRef();
         mEmotes = nullptr;
@@ -68,7 +68,7 @@ void EmotePage::draw(Graphics *const graphics)
 
     if (mRedraw)
     {
-        if (!mEmotes)
+        if (mEmotes == nullptr)
             return;
 
         const std::vector<Image*> &images = mEmotes->getImages();
@@ -82,7 +82,7 @@ void EmotePage::draw(Graphics *const graphics)
         FOR_EACH (std::vector<Image*>::const_iterator, it, images)
         {
             const Image *const image = *it;
-            if (image)
+            if (image != nullptr)
             {
                 graphics->calcTileCollection(mVertexes, image, x, y);
                 x += emoteWidth;
@@ -104,7 +104,7 @@ void EmotePage::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("EmotePage::safeDraw")
 
-    if (!mEmotes)
+    if (mEmotes == nullptr)
         return;
 
     const std::vector<Image*> &images = mEmotes->getImages();
@@ -116,7 +116,7 @@ void EmotePage::safeDraw(Graphics *const graphics)
     FOR_EACH (std::vector<Image*>::const_iterator, it, images)
     {
         const Image *const image = *it;
-        if (image)
+        if (image != nullptr)
         {
             graphics->drawImage(image, x, y);
             x += emoteWidth;
diff --git a/src/gui/widgets/emoteshortcutcontainer.cpp b/src/gui/widgets/emoteshortcutcontainer.cpp
index 0d75051eb..37acf7263 100644
--- a/src/gui/widgets/emoteshortcutcontainer.cpp
+++ b/src/gui/widgets/emoteshortcutcontainer.cpp
@@ -57,14 +57,14 @@ EmoteShortcutContainer::EmoteShortcutContainer(Widget2 *restrict const
     mEmoteClicked(false),
     mEmoteMoved(0)
 {
-    if (mBackgroundImg)
+    if (mBackgroundImg != nullptr)
         mBackgroundImg->setAlpha(settings.guiAlpha);
 
     // Setup emote sprites
     for (int i = 0; i <= EmoteDB::getLast(); i++)
     {
         const EmoteSprite *const sprite = EmoteDB::getSprite(i, true);
-        if (sprite && sprite->sprite)
+        if ((sprite != nullptr) && (sprite->sprite != nullptr))
             mEmoteImg.push_back(sprite);
     }
 
@@ -85,13 +85,13 @@ void EmoteShortcutContainer::setWidget2(const Widget2 *restrict const widget)
 
 void EmoteShortcutContainer::draw(Graphics *restrict graphics) restrict2
 {
-    if (!emoteShortcut)
+    if (emoteShortcut == nullptr)
         return;
 
     BLOCK_START("EmoteShortcutContainer::draw")
     if (settings.guiAlpha != mAlpha)
     {
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
         mAlpha = settings.guiAlpha;
     }
@@ -105,10 +105,10 @@ void EmoteShortcutContainer::draw(Graphics *restrict graphics) restrict2
     for (unsigned i = 0; i < sz; i++)
     {
         const EmoteSprite *restrict const emoteImg = mEmoteImg[i];
-        if (emoteImg)
+        if (emoteImg != nullptr)
         {
             const AnimatedSprite *restrict const sprite = emoteImg->sprite;
-            if (sprite)
+            if (sprite != nullptr)
             {
                 sprite->draw(graphics,
                     (i % mGridWidth) * mBoxWidth + 2,
@@ -137,13 +137,13 @@ void EmoteShortcutContainer::draw(Graphics *restrict graphics) restrict2
 
 void EmoteShortcutContainer::safeDraw(Graphics *restrict graphics) restrict2
 {
-    if (!emoteShortcut)
+    if (emoteShortcut == nullptr)
         return;
 
     BLOCK_START("EmoteShortcutContainer::draw")
     if (settings.guiAlpha != mAlpha)
     {
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
         mAlpha = settings.guiAlpha;
     }
@@ -157,10 +157,10 @@ void EmoteShortcutContainer::safeDraw(Graphics *restrict graphics) restrict2
     for (unsigned i = 0; i < sz; i++)
     {
         const EmoteSprite *restrict const emoteImg = mEmoteImg[i];
-        if (emoteImg)
+        if (emoteImg != nullptr)
         {
             const AnimatedSprite *restrict const sprite = emoteImg->sprite;
-            if (sprite)
+            if (sprite != nullptr)
             {
                 sprite->draw(graphics,
                     (i % mGridWidth) * mBoxWidth + 2,
@@ -199,7 +199,7 @@ void EmoteShortcutContainer::mousePressed(MouseEvent &restrict event) restrict2
 
     if (event.getButton() == MouseButton::LEFT)
     {
-        if (!emoteShortcut)
+        if (emoteShortcut == nullptr)
             return;
 
         const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -214,14 +214,14 @@ void EmoteShortcutContainer::mousePressed(MouseEvent &restrict event) restrict2
             emoteShortcut->setEmote(index);
             emoteShortcut->setEmoteSelected(0);
         }
-        else if (emoteShortcut->getEmote(index))
+        else if (emoteShortcut->getEmote(index) != 0u)
         {
             mEmoteClicked = true;
         }
     }
     else if (event.getButton() == MouseButton::RIGHT)
     {
-        if (popupMenu)
+        if (popupMenu != nullptr)
         {
             event.consume();
             popupMenu->showEmoteType();
@@ -232,7 +232,7 @@ void EmoteShortcutContainer::mousePressed(MouseEvent &restrict event) restrict2
 void EmoteShortcutContainer::mouseReleased(MouseEvent &restrict event)
                                            restrict2
 {
-    if (!emoteShortcut)
+    if (emoteShortcut == nullptr)
         return;
 
     if (event.getButton() == MouseButton::LEFT)
@@ -248,12 +248,12 @@ void EmoteShortcutContainer::mouseReleased(MouseEvent &restrict event)
             return;
         }
 
-        if (mEmoteMoved)
+        if (mEmoteMoved != 0u)
         {
             emoteShortcut->setEmotes(index, mEmoteMoved);
             mEmoteMoved = 0;
         }
-        else if (emoteShortcut->getEmote(index) && mEmoteClicked)
+        else if ((emoteShortcut->getEmote(index) != 0u) && mEmoteClicked)
         {
             emoteShortcut->useEmote(index + 1);
         }
@@ -264,7 +264,7 @@ void EmoteShortcutContainer::mouseReleased(MouseEvent &restrict event)
 
 void EmoteShortcutContainer::mouseMoved(MouseEvent &restrict event) restrict2
 {
-    if (!emoteShortcut || !textPopup)
+    if ((emoteShortcut == nullptr) || (textPopup == nullptr))
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -274,7 +274,7 @@ void EmoteShortcutContainer::mouseMoved(MouseEvent &restrict event) restrict2
 
     textPopup->setVisible(Visible_false);
 
-    if (CAST_SIZE(index) < mEmoteImg.size() && mEmoteImg[index])
+    if (CAST_SIZE(index) < mEmoteImg.size() && (mEmoteImg[index] != nullptr))
     {
         const EmoteSprite *restrict const sprite = mEmoteImg[index];
         textPopup->show(viewport->mMouseX, viewport->mMouseY,
@@ -285,13 +285,13 @@ void EmoteShortcutContainer::mouseMoved(MouseEvent &restrict event) restrict2
 void EmoteShortcutContainer::mouseExited(MouseEvent &restrict event A_UNUSED)
                                          restrict2
 {
-    if (textPopup)
+    if (textPopup != nullptr)
         textPopup->setVisible(Visible_false);
 }
 
 void EmoteShortcutContainer::widgetHidden(const Event &restrict event A_UNUSED)
                                           restrict2
 {
-    if (textPopup)
+    if (textPopup != nullptr)
         textPopup->setVisible(Visible_false);
 }
diff --git a/src/gui/widgets/extendedlistbox.cpp b/src/gui/widgets/extendedlistbox.cpp
index 921dfee7f..ebbb07bf3 100644
--- a/src/gui/widgets/extendedlistbox.cpp
+++ b/src/gui/widgets/extendedlistbox.cpp
@@ -35,13 +35,13 @@ ExtendedListBox::ExtendedListBox(const Widget2 *const widget,
                                  const std::string &skin,
                                  const unsigned int rowHeight) :
     ListBox(widget, listModel, skin),
-    mImagePadding(mSkin ? mSkin->getOption("imagePadding") : 0),
-    mSpacing(mSkin ? mSkin->getOption("spacing") : 0),
+    mImagePadding(mSkin != nullptr ? mSkin->getOption("imagePadding") : 0),
+    mSpacing(mSkin != nullptr ? mSkin->getOption("spacing") : 0),
     mHeight(0),
     mListItems(),
     mSelectedItems()
 {
-    if (rowHeight)
+    if (rowHeight != 0u)
         mRowHeight = rowHeight;
 }
 
@@ -51,7 +51,7 @@ ExtendedListBox::~ExtendedListBox()
 
 void ExtendedListBox::draw(Graphics *const graphics)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return;
 
     BLOCK_START("ExtendedListBox::draw")
@@ -81,7 +81,7 @@ void ExtendedListBox::draw(Graphics *const graphics)
         int strWidth = font->getWidth(str) + 8;
 
         const Image *const image = model->getImageAt(row);
-        if (image)
+        if (image != nullptr)
             strWidth += image->getWidth() + mImagePadding;
 
         std::vector<ExtendedListBoxItem> &list =
@@ -145,7 +145,7 @@ void ExtendedListBox::draw(Graphics *const graphics)
         if (item.image)
         {
             const Image *const image = model->getImageAt(row1);
-            if (image)
+            if (image != nullptr)
             {
                 graphics->drawImage(image,
                     mImagePadding,
@@ -160,7 +160,7 @@ void ExtendedListBox::draw(Graphics *const graphics)
         const int row1 = item.row;
         const int y1 = item.y;
         const Image *const image = model->getImageAt(row1);
-        if (!image || !item.image)
+        if ((image == nullptr) || !item.image)
         {
             font->drawString(graphics,
                 mForegroundColor, mForegroundColor2,
@@ -182,7 +182,7 @@ void ExtendedListBox::draw(Graphics *const graphics)
         const int row1 = item.row;
         const int y1 = item.y;
         const Image *const image = model->getImageAt(row1);
-        if (!image || !item.image)
+        if ((image == nullptr) || !item.image)
         {
             font->drawString(graphics,
                 mForegroundSelectedColor, mForegroundSelectedColor2,
@@ -205,7 +205,7 @@ void ExtendedListBox::draw(Graphics *const graphics)
         if (item.image)
         {
             const Image *const image = model->getImageAt(row1);
-            if (image)
+            if (image != nullptr)
             {
                 graphics->drawImage(image,
                     mImagePadding,
@@ -224,7 +224,7 @@ void ExtendedListBox::safeDraw(Graphics *const graphics)
 
 void ExtendedListBox::adjustSize()
 {
-    if (mHeight)
+    if (mHeight != 0)
         setHeight(mHeight + 2 * mPadding);
     else
         ListBox::adjustSize();
diff --git a/src/gui/widgets/flowcontainer.cpp b/src/gui/widgets/flowcontainer.cpp
index 7f33208c2..ee3181636 100644
--- a/src/gui/widgets/flowcontainer.cpp
+++ b/src/gui/widgets/flowcontainer.cpp
@@ -34,9 +34,9 @@ FlowContainer::FlowContainer(const Widget2 *const widget,
     mGridHeight(1)
 {
     addWidgetListener(this);
-    if (!mBoxWidth)
+    if (mBoxWidth == 0)
         mBoxWidth = 1;
-    if (!mBoxHeight)
+    if (mBoxHeight == 0)
         mBoxHeight = 1;
 }
 
@@ -50,7 +50,7 @@ void FlowContainer::widgetResized(const Event &event A_UNUSED)
 
     const int itemCount = CAST_S32(mWidgets.size());
 
-    if (!mBoxWidth)
+    if (mBoxWidth == 0)
         mGridWidth = getWidth();
     else
         mGridWidth = getWidth() / mBoxWidth;
@@ -88,7 +88,7 @@ void FlowContainer::widgetResized(const Event &event A_UNUSED)
 
 void FlowContainer::add(Widget *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     Container::add(widget);
diff --git a/src/gui/widgets/guitable.cpp b/src/gui/widgets/guitable.cpp
index 3c22dd4b1..392755a20 100644
--- a/src/gui/widgets/guitable.cpp
+++ b/src/gui/widgets/guitable.cpp
@@ -69,7 +69,7 @@ GuiTable::GuiTable(const Widget2 *const widget,
 
 GuiTable::~GuiTable()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     uninstallActionListeners();
@@ -83,7 +83,7 @@ const TableModel *GuiTable::getModel() const
 
 void GuiTable::setModel(TableModel *const new_model)
 {
-    if (mModel)
+    if (mModel != nullptr)
     {
         uninstallActionListeners();
         mModel->removeListener(this);
@@ -98,7 +98,7 @@ void GuiTable::setModel(TableModel *const new_model)
 
 void GuiTable::recomputeDimensions()
 {
-    if (!mModel)
+    if (mModel == nullptr)
         return;
 
     const int rows_nr = mModel->getRows();
@@ -211,7 +211,7 @@ void GuiTable::installActionListeners()
         for (int column = 0; column < columns; ++column)
         {
             Widget *const widget = mModel->getElementAt(row, column);
-            if (widget)
+            if (widget != nullptr)
             {
                 mActionListeners2.push_back(new GuiTableActionListener(
                     this, widget, row, column));
@@ -225,7 +225,7 @@ void GuiTable::installActionListeners()
 // -- widget ops
 void GuiTable::draw(Graphics *const graphics)
 {
-    if (!getRowHeight())
+    if (getRowHeight() == 0)
         return;
 
     BLOCK_START("GuiTable::draw")
@@ -246,7 +246,7 @@ void GuiTable::draw(Graphics *const graphics)
     // First, determine how many rows we need to draw,
     // and where we should start.
     int rHeight = getRowHeight();
-    if (!rHeight)
+    if (rHeight == 0)
         rHeight = 1;
     int first_row = -(y / rHeight);
 
@@ -288,7 +288,7 @@ void GuiTable::draw(Graphics *const graphics)
                 CAST_S32(c));
             const int cWidth = CAST_S32(getColumnWidth(
                 CAST_S32(c)));
-            if (widget)
+            if (widget != nullptr)
             {
                 Rect bounds(x_offset, y_offset, cWidth, rHeight);
 
@@ -331,7 +331,7 @@ void GuiTable::draw(Graphics *const graphics)
         y_offset += rHeight;
     }
 
-    if (mTopWidget)
+    if (mTopWidget != nullptr)
     {
         const Rect &bounds = mTopWidget->getDimension();
         graphics->pushClipArea(bounds);
@@ -343,7 +343,7 @@ void GuiTable::draw(Graphics *const graphics)
 
 void GuiTable::safeDraw(Graphics *const graphics)
 {
-    if (!getRowHeight())
+    if (getRowHeight() == 0)
         return;
 
     BLOCK_START("GuiTable::draw")
@@ -364,7 +364,7 @@ void GuiTable::safeDraw(Graphics *const graphics)
     // First, determine how many rows we need to draw,
     // and where we should start.
     int rHeight = getRowHeight();
-    if (!rHeight)
+    if (rHeight == 0)
         rHeight = 1;
     int first_row = -(y / rHeight);
 
@@ -406,7 +406,7 @@ void GuiTable::safeDraw(Graphics *const graphics)
                 CAST_S32(c));
             const int cWidth = CAST_S32(getColumnWidth(
                 CAST_S32(c)));
-            if (widget)
+            if (widget != nullptr)
             {
                 Rect bounds(x_offset, y_offset, cWidth, rHeight);
 
@@ -449,7 +449,7 @@ void GuiTable::safeDraw(Graphics *const graphics)
         y_offset += rHeight;
     }
 
-    if (mTopWidget)
+    if (mTopWidget != nullptr)
     {
         const Rect &bounds = mTopWidget->getDimension();
         graphics->pushClipArea(bounds);
@@ -513,7 +513,7 @@ void GuiTable::keyPressed(KeyEvent& event)
         setSelectedColumn(0);
         event.consume();
     }
-    else if (action == InputAction::GUI_END && mModel)
+    else if (action == InputAction::GUI_END && (mModel != nullptr))
     {
         setSelectedRow(mModel->getRows() - 1);
         setSelectedColumn(mModel->getColumns() - 1);
@@ -596,13 +596,16 @@ Widget *GuiTable::getWidgetAt(int x, int y)
     const int row = getRowForY(y);
     const int column = getColumnForX(x);
 
-    if (mTopWidget && mTopWidget->getDimension().isPointInRect(x, y))
+    if (mTopWidget != nullptr &&
+        mTopWidget->getDimension().isPointInRect(x, y))
+    {
         return mTopWidget;
+    }
 
-    if (mModel && row > -1 && column > -1)
+    if ((mModel != nullptr) && row > -1 && column > -1)
     {
         Widget *const w = mModel->getElementAt(row, column);
-        if (w && w->isFocusable())
+        if ((w != nullptr) && w->isFocusable())
             return w;
         else
             return nullptr;  // Grab the event locally
@@ -648,7 +651,7 @@ void GuiTable::setFocusHandler(FocusHandler *const focusHandler)
 {
     // add check for focusHandler. may be need remove it?
 
-    if (!focusHandler)
+    if (focusHandler == nullptr)
         return;
 
     Widget::setFocusHandler(focusHandler);
@@ -660,7 +663,7 @@ void GuiTable::setFocusHandler(FocusHandler *const focusHandler)
         for (int c = 0; c < cols ; ++c)
         {
             Widget *const w = mModel->getElementAt(r, c);
-            if (w)
+            if (w != nullptr)
                 w->setFocusHandler(focusHandler);
         }
     }
@@ -668,7 +671,7 @@ void GuiTable::setFocusHandler(FocusHandler *const focusHandler)
 
 void GuiTable::requestFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
     Widget::requestFocus();
 }
diff --git a/src/gui/widgets/horizontcontainer.cpp b/src/gui/widgets/horizontcontainer.cpp
index 5b3b08d16..8a026329a 100644
--- a/src/gui/widgets/horizontcontainer.cpp
+++ b/src/gui/widgets/horizontcontainer.cpp
@@ -45,7 +45,7 @@ void HorizontContainer::add(Widget *const widget)
 
 void HorizontContainer::add(Widget *const widget, const int spacing)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     Container::add(widget);
diff --git a/src/gui/widgets/icon.cpp b/src/gui/widgets/icon.cpp
index 8cb43db6d..dbe46a21a 100644
--- a/src/gui/widgets/icon.cpp
+++ b/src/gui/widgets/icon.cpp
@@ -39,7 +39,7 @@ Icon::Icon(const Widget2 *const widget,
     mImage(Loader::getImage(file)),
     mAutoRelease(autoRelease)
 {
-    if (mImage)
+    if (mImage != nullptr)
     {
         const SDL_Rect &bounds = mImage->mBounds;
         setSize(bounds.w, bounds.h);
@@ -54,7 +54,7 @@ Icon::Icon(const Widget2 *const widget,
     mImage(image),
     mAutoRelease(autoRelease)
 {
-    if (mImage)
+    if (mImage != nullptr)
     {
         const SDL_Rect &bounds = mImage->mBounds;
         setSize(bounds.w, bounds.h);
@@ -64,16 +64,16 @@ Icon::Icon(const Widget2 *const widget,
 
 Icon::~Icon()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
-    if (mImage && mAutoRelease == AutoRelease_true)
+    if ((mImage != nullptr) && mAutoRelease == AutoRelease_true)
         mImage->decRef();
 }
 
 void Icon::setImage(Image *const image)
 {
     mImage = image;
-    if (mImage)
+    if (mImage != nullptr)
     {
         const SDL_Rect &bounds = mImage->mBounds;
         setSize(bounds.w, bounds.h);
@@ -83,7 +83,7 @@ void Icon::setImage(Image *const image)
 void Icon::draw(Graphics *const graphics)
 {
     BLOCK_START("Icon::draw")
-    if (mImage)
+    if (mImage != nullptr)
     {
         graphics->drawImage(mImage,
             (mDimension.width - mImage->mBounds.w) / 2,
@@ -95,7 +95,7 @@ void Icon::draw(Graphics *const graphics)
 void Icon::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("Icon::draw")
-    if (mImage)
+    if (mImage != nullptr)
     {
         graphics->drawImage(mImage,
             (mDimension.width - mImage->mBounds.w) / 2,
diff --git a/src/gui/widgets/itemcontainer.cpp b/src/gui/widgets/itemcontainer.cpp
index 857467f63..15e2df093 100644
--- a/src/gui/widgets/itemcontainer.cpp
+++ b/src/gui/widgets/itemcontainer.cpp
@@ -88,7 +88,7 @@ namespace
             {
                 const Item *const item1 = pair1->mItem;
                 const Item *const item2 = pair2->mItem;
-                if (!item1 || !item2)
+                if ((item1 == nullptr) || (item2 == nullptr))
                     return false;
 
                 const std::string name1 = item1->getInfo().getName(
@@ -112,7 +112,7 @@ namespace
             bool operator() (const ItemIdPair *const pair1,
                              const ItemIdPair *const pair2) const
             {
-                if (!pair1->mItem || !pair2->mItem)
+                if ((pair1->mItem == nullptr) || (pair2->mItem == nullptr))
                     return false;
 
                 const int id1 = pair1->mItem->getId();
@@ -134,7 +134,7 @@ namespace
             bool operator() (const ItemIdPair *const pair1,
                              const ItemIdPair *const pair2) const
             {
-                if (!pair1->mItem || !pair2->mItem)
+                if ((pair1->mItem == nullptr) || (pair2->mItem == nullptr))
                     return false;
 
                 const int w1 = pair1->mItem->getInfo().getWeight();
@@ -164,7 +164,7 @@ namespace
             bool operator() (const ItemIdPair *const pair1,
                              const ItemIdPair *const pair2) const
             {
-                if (!pair1->mItem || !pair2->mItem)
+                if ((pair1->mItem == nullptr) || (pair2->mItem == nullptr))
                     return false;
 
                 const int c1 = pair1->mItem->getQuantity();
@@ -194,7 +194,7 @@ namespace
             bool operator() (const ItemIdPair *const pair1,
                              const ItemIdPair *const pair2) const
             {
-                if (!pair1->mItem || !pair2->mItem)
+                if ((pair1->mItem == nullptr) || (pair2->mItem == nullptr))
                     return false;
 
                 const ItemInfo &info1 = pair1->mItem->getInfo();
@@ -232,7 +232,7 @@ ItemContainer::ItemContainer(const Widget2 *const widget,
     mCellBackgroundImg(Theme::getImageFromThemeXml("inventory_cell.xml", "")),
     mName(),
     mShowMatrix(nullptr),
-    mSkin(theme ? theme->load("itemcontainer.xml", "") : nullptr),
+    mSkin(theme != nullptr ? theme->load("itemcontainer.xml", "") : nullptr),
     mVertexes(new ImageCollection),
     mEquipedColor(getThemeColor(ThemeColorId::ITEM_EQUIPPED)),
     mEquipedColor2(getThemeColor(ThemeColorId::ITEM_EQUIPPED_OUTLINE)),
@@ -246,12 +246,12 @@ ItemContainer::ItemContainer(const Widget2 *const widget,
     mTag(0),
     mSortType(0),
     mClicks(1),
-    mBoxWidth(mSkin ? mSkin->getOption("boxWidth", 35) : 35),
-    mBoxHeight(mSkin ? mSkin->getOption("boxHeight", 43) : 43),
-    mEquippedTextPadding(mSkin ? mSkin->getOption(
+    mBoxWidth(mSkin != nullptr ? mSkin->getOption("boxWidth", 35) : 35),
+    mBoxHeight(mSkin != nullptr ? mSkin->getOption("boxHeight", 43) : 43),
+    mEquippedTextPadding(mSkin != nullptr ? mSkin->getOption(
                          "equippedTextPadding", 29) : 29),
-    mPaddingItemX(mSkin ? mSkin->getOption("paddingItemX", 0) : 0),
-    mPaddingItemY(mSkin ? mSkin->getOption("paddingItemY", 0) : 0),
+    mPaddingItemX(mSkin != nullptr ? mSkin->getOption("paddingItemX", 0) : 0),
+    mPaddingItemY(mSkin != nullptr ? mSkin->getOption("paddingItemY", 0) : 0),
     mMaxColumns(maxColumns),
     mSelectionStatus(SEL_NONE),
     mForceQuantity(forceQuantity),
@@ -267,26 +267,26 @@ ItemContainer::ItemContainer(const Widget2 *const widget,
 
 ItemContainer::~ItemContainer()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
-    if (mSelImg)
+    if (mSelImg != nullptr)
     {
         mSelImg->decRef();
         mSelImg = nullptr;
     }
-    if (mProtectedImg)
+    if (mProtectedImg != nullptr)
     {
         mProtectedImg->decRef();
         mProtectedImg = nullptr;
     }
-    if (mCellBackgroundImg)
+    if (mCellBackgroundImg != nullptr)
     {
         mCellBackgroundImg->decRef();
         mCellBackgroundImg = nullptr;
     }
 
-    if (theme)
+    if (theme != nullptr)
         theme->unload(mSkin);
 
     delete []mShowMatrix;
@@ -298,7 +298,7 @@ void ItemContainer::logic()
     BLOCK_START("ItemContainer::logic")
     Widget::logic();
 
-    if (!mInventory)
+    if (mInventory == nullptr)
     {
         BLOCK_END("ItemContainer::logic")
         return;
@@ -316,13 +316,13 @@ void ItemContainer::logic()
 
 void ItemContainer::draw(Graphics *const graphics)
 {
-    if (!mInventory || !mShowMatrix)
+    if ((mInventory == nullptr) || (mShowMatrix == nullptr))
         return;
 
     BLOCK_START("ItemContainer::draw")
     Font *const font = getFont();
 
-    if (mCellBackgroundImg)
+    if (mCellBackgroundImg != nullptr)
     {
         if (mRedraw || graphics->getRedraw())
         {
@@ -367,22 +367,22 @@ void ItemContainer::draw(Graphics *const graphics)
             const Item *const item = mInventory->getItem(
                 mShowMatrix[itemIndex]);
 
-            if (!item || item->getId() == 0)
+            if ((item == nullptr) || item->getId() == 0)
                 continue;
 
             Image *const image = item->getImage();
-            if (image)
+            if (image != nullptr)
             {
                 if (mShowMatrix[itemIndex] == mSelectedIndex)
                 {
-                    if (mSelImg)
+                    if (mSelImg != nullptr)
                         graphics->drawImage(mSelImg, itemX, itemY);
                 }
                 image->setAlpha(1.0F);  // ensure the image if fully drawn...
                 graphics->drawImage(image,
                     itemX + mPaddingItemX,
                     itemY + mPaddingItemY);
-                if (mProtectedImg && PlayerInfo::isItemProtected(
+                if ((mProtectedImg != nullptr) && PlayerInfo::isItemProtected(
                     item->getId()))
                 {
                     graphics->drawImage(mProtectedImg,
@@ -408,7 +408,7 @@ void ItemContainer::draw(Graphics *const graphics)
             const Item *const item = mInventory->getItem(
                 mShowMatrix[itemIndex]);
 
-            if (!item || item->getId() == 0)
+            if ((item == nullptr) || item->getId() == 0)
                 continue;
 
             // Draw item caption
@@ -447,13 +447,13 @@ void ItemContainer::draw(Graphics *const graphics)
 
 void ItemContainer::safeDraw(Graphics *const graphics)
 {
-    if (!mInventory || !mShowMatrix)
+    if ((mInventory == nullptr) || (mShowMatrix == nullptr))
         return;
 
     BLOCK_START("ItemContainer::draw")
     Font *const font = getFont();
 
-    if (mCellBackgroundImg)
+    if (mCellBackgroundImg != nullptr)
     {
         const int invSize = mInventory->getSize();
         const int maxRows = mShowEmptyRows == ShowEmptyRows_true ?
@@ -489,22 +489,22 @@ void ItemContainer::safeDraw(Graphics *const graphics)
             const Item *const item = mInventory->getItem(
                 mShowMatrix[itemIndex]);
 
-            if (!item || item->getId() == 0)
+            if ((item == nullptr) || item->getId() == 0)
                 continue;
 
             Image *const image = item->getImage();
-            if (image)
+            if (image != nullptr)
             {
                 if (mShowMatrix[itemIndex] == mSelectedIndex)
                 {
-                    if (mSelImg)
+                    if (mSelImg != nullptr)
                         graphics->drawImage(mSelImg, itemX, itemY);
                 }
                 image->setAlpha(1.0F);  // ensure the image if fully drawn...
                 graphics->drawImage(image,
                     itemX + mPaddingItemX,
                     itemY + mPaddingItemY);
-                if (mProtectedImg && PlayerInfo::isItemProtected(
+                if ((mProtectedImg != nullptr) && PlayerInfo::isItemProtected(
                     item->getId()))
                 {
                     graphics->drawImage(mProtectedImg,
@@ -530,7 +530,7 @@ void ItemContainer::safeDraw(Graphics *const graphics)
             const Item *const item = mInventory->getItem(
                 mShowMatrix[itemIndex]);
 
-            if (!item || item->getId() == 0)
+            if ((item == nullptr) || item->getId() == 0)
                 continue;
 
             // Draw item caption
@@ -592,7 +592,7 @@ void ItemContainer::setSelectedIndex(const int newIndex)
 
 Item *ItemContainer::getSelectedItem() const
 {
-    if (mInventory)
+    if (mInventory != nullptr)
         return mInventory->getItem(mSelectedIndex);
     else
         return nullptr;
@@ -602,7 +602,7 @@ void ItemContainer::distributeValueChangedEvent()
 {
     FOR_EACH (SelectionListenerIterator, i, mSelectionListeners)
     {
-        if (*i)
+        if (*i != nullptr)
         {
             SelectionEvent event(this);
             (*i)->valueChanged(event);
@@ -620,7 +620,7 @@ void ItemContainer::keyReleased(KeyEvent &event A_UNUSED)
 
 void ItemContainer::mousePressed(MouseEvent &event)
 {
-    if (!mInventory)
+    if (mInventory == nullptr)
         return;
 
     const MouseButtonT button = event.getButton();
@@ -636,7 +636,7 @@ void ItemContainer::mousePressed(MouseEvent &event)
         Item *const item = mInventory->getItem(index);
 
         // put item name into chat window
-        if (item && mDescItems && chatWindow)
+        if ((item != nullptr) && mDescItems && (chatWindow != nullptr))
             chatWindow->addItemText(item->getInfo().getName());
 
         DragDropSourceT src = DragDropSource::Empty;
@@ -674,7 +674,7 @@ void ItemContainer::mousePressed(MouseEvent &event)
             dragDrop.select(item);
             mSelectionStatus = SEL_DESELECTING;
         }
-        else if (item && item->getId())
+        else if ((item != nullptr) && (item->getId() != 0))
         {
             if (index >= 0)
             {
@@ -683,16 +683,16 @@ void ItemContainer::mousePressed(MouseEvent &event)
                 setSelectedIndex(index);
                 mSelectionStatus = SEL_SELECTING;
 
-                if (itemShortcutWindow)
+                if (itemShortcutWindow != nullptr)
                 {
                     const int num = itemShortcutWindow->getTabIndex();
                     if (num >= 0 && num < CAST_S32(SHORTCUT_TABS))
                     {
-                        if (itemShortcut[num])
+                        if (itemShortcut[num] != nullptr)
                             itemShortcut[num]->setItemSelected(item);
                     }
                 }
-                if (shopWindow)
+                if (shopWindow != nullptr)
                     shopWindow->setItemSelected(item->getId());
             }
         }
@@ -712,8 +712,12 @@ void ItemContainer::mouseDragged(MouseEvent &event A_UNUSED)
 
 void ItemContainer::mouseReleased(MouseEvent &event)
 {
-    if (mClicks == 2 || !inventoryHandler || !tradeHandler)
+    if (mClicks == 2 ||
+        inventoryHandler == nullptr ||
+        tradeHandler == nullptr)
+    {
         return;
+    }
 
     switch (mSelectionStatus)
     {
@@ -742,7 +746,7 @@ void ItemContainer::mouseReleased(MouseEvent &event)
         inventoryHandler->moveItem(mSelectedIndex, index);
         selectNone();
     }
-    else if (mInventory)
+    else if (mInventory != nullptr)
     {
         const DragDropSourceT src = dragDrop.getSource();
         DragDropSourceT dst = DragDropSource::Empty;
@@ -809,7 +813,7 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                 return;
             if (index == mSelectedIndex || mSelectedIndex == -1)
                 return;
-            if (inventoryWindow)
+            if (inventoryWindow != nullptr)
                 inventoryWindow->combineItems(index, mSelectedIndex);
             return;
         }
@@ -845,7 +849,7 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                  || dst == DragDropSource::Mail))
         {
             inventory = PlayerInfo::getInventory();
-            if (inventory)
+            if (inventory != nullptr)
             {
                 Item *const item = inventory->getItem(dragDrop.getTag());
                 if (mInventory->addVirtualItem(
@@ -868,7 +872,7 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                 const int index = getSlotByXY(event.getX(), event.getY());
                 if (index == Inventory::NO_SLOT_INDEX)
                 {
-                    if (inventory)
+                    if (inventory != nullptr)
                         inventory->virtualRestore(item, 1);
                     mInventory->removeItemAt(dragDrop.getTag());
                     return;
@@ -886,17 +890,17 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                     Equipm_false,
                     Equipped_false);
                 Item *const item2 = mInventory->getItem(index);
-                if (item2)
+                if (item2 != nullptr)
                     item2->setTag(item->getTag());
                 mInventory->removeItemAt(dragDrop.getTag());
             }
             else
             {
-                if (inventory)
+                if (inventory != nullptr)
                 {
                     const Item *const item = inventory->getItem(
                         dragDrop.getTag());
-                    if (item)
+                    if (item != nullptr)
                     {
                         inventory->virtualRestore(item, 1);
                         mInventory->removeItemAt(dragDrop.getTag());
@@ -909,10 +913,10 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                  dst == DragDropSource::Craft)
         {
             inventory = PlayerInfo::getInventory();
-            if (inventory)
+            if (inventory != nullptr)
             {
                 Item *const item = inventory->getItem(dragDrop.getTag());
-                if (!item || item->isEquipped() == Equipped_true)
+                if ((item == nullptr) || item->isEquipped() == Equipped_true)
                     return;
                 const int slot = getSlotByXY(event.getX(), event.getY());
                 if (item->getQuantity() > 1
@@ -948,7 +952,7 @@ void ItemContainer::mouseReleased(MouseEvent &event)
                 const int index = getSlotByXY(event.getX(), event.getY());
                 if (index == Inventory::NO_SLOT_INDEX)
                 {
-                    if (inventory)
+                    if (inventory != nullptr)
                     {
                         inventory->virtualRestore(item,
                             item->getQuantity());
@@ -960,11 +964,11 @@ void ItemContainer::mouseReleased(MouseEvent &event)
             }
             else
             {
-                if (inventory)
+                if (inventory != nullptr)
                 {
                     const Item *const item = inventory->getItem(
                         dragDrop.getTag());
-                    if (item)
+                    if (item != nullptr)
                     {
                         inventory->virtualRestore(item,
                             item->getQuantity());
@@ -977,19 +981,19 @@ void ItemContainer::mouseReleased(MouseEvent &event)
         else if (src == DragDropSource::Mail)
         {
             inventory = PlayerInfo::getInventory();
-            if (inventory)
+            if (inventory != nullptr)
             {
                 const Item *const item = inventory->getItem(dragDrop.getTag());
-                if (item)
+                if (item != nullptr)
                     mInventory->removeItemAt(dragDrop.getTag());
             }
             return;
         }
 
-        if (inventory)
+        if (inventory != nullptr)
         {
             const Item *const item = inventory->getItem(dragDrop.getTag());
-            if (item)
+            if (item != nullptr)
             {
                 if (srcContainer != InventoryType::TypeEnd)
                 {   // inventory <--> storage, cart
@@ -1013,13 +1017,13 @@ void ItemContainer::mouseReleased(MouseEvent &event)
 
 void ItemContainer::mouseMoved(MouseEvent &event)
 {
-    if (!mInventory)
+    if (mInventory == nullptr)
         return;
 
     const Item *const item = mInventory->getItem(
         getSlotIndex(event.getX(), event.getY()));
 
-    if (item && viewport)
+    if ((item != nullptr) && (viewport != nullptr))
     {
         itemPopup->setItem(item, false);
         itemPopup->position(viewport->mMouseX, viewport->mMouseY);
@@ -1057,7 +1061,7 @@ void ItemContainer::widgetMoved(const Event &event A_UNUSED)
 
 void ItemContainer::adjustHeight()
 {
-    if (!mGridColumns)
+    if (mGridColumns == 0)
         return;
 
     mGridRows = (mLastUsedSlot + 1) / mGridColumns;
@@ -1081,7 +1085,7 @@ void ItemContainer::adjustHeight()
 
 void ItemContainer::updateMatrix()
 {
-    if (!mInventory)
+    if (mInventory == nullptr)
         return;
 
     mRedraw = true;
@@ -1100,7 +1104,9 @@ void ItemContainer::updateMatrix()
     {
         Item *const item = mInventory->getItem(idx);
 
-        if (!item || item->getId() == 0 || !item->isHaveTag(mTag))
+        if (item == nullptr ||
+            item->getId() == 0 ||
+            !item->isHaveTag(mTag))
         {
             if (mShowEmptyRows == ShowEmptyRows_true)
                 sortedItems.push_back(new ItemIdPair(idx, nullptr));
@@ -1174,7 +1180,7 @@ void ItemContainer::updateMatrix()
 
 int ItemContainer::getSlotIndex(int x, int y) const
 {
-    if (!mShowMatrix)
+    if (mShowMatrix == nullptr)
         return Inventory::NO_SLOT_INDEX;
 
     if (x < mDimension.width && y < mDimension.height && x >= 0 && y >= 0)
@@ -1194,7 +1200,7 @@ int ItemContainer::getSlotIndex(int x, int y) const
 
 int ItemContainer::getSlotByXY(int x, int y) const
 {
-    if (!mShowMatrix)
+    if (mShowMatrix == nullptr)
         return Inventory::NO_SLOT_INDEX;
 
     if (x < mDimension.width && y < mDimension.height && x >= 0 && y >= 0)
@@ -1223,7 +1229,7 @@ void ItemContainer::setSortType(const int sortType)
 
 void ItemContainer::setCellBackgroundImage(const std::string &xmlName)
 {
-    if (mCellBackgroundImg)
+    if (mCellBackgroundImg != nullptr)
         mCellBackgroundImg->decRef();
     mCellBackgroundImg = Theme::getImageFromThemeXml(xmlName, "");
     mRedraw = true;
diff --git a/src/gui/widgets/itemcontainer.h b/src/gui/widgets/itemcontainer.h
index 2d732ad3c..ba640d374 100644
--- a/src/gui/widgets/itemcontainer.h
+++ b/src/gui/widgets/itemcontainer.h
@@ -126,7 +126,7 @@ class ItemContainer final : public Widget,
         void updateMatrix();
 
         bool getClickCount() const noexcept2 A_WARN_UNUSED
-        { return mClicks; }
+        { return mClicks != 0; }
 
         void unsetInventory() noexcept2
         { mInventory = nullptr; }
diff --git a/src/gui/widgets/itemlinkhandler.cpp b/src/gui/widgets/itemlinkhandler.cpp
index 90a26a4a0..295e41d16 100644
--- a/src/gui/widgets/itemlinkhandler.cpp
+++ b/src/gui/widgets/itemlinkhandler.cpp
@@ -95,7 +95,7 @@ void ItemLinkHandler::handleCommandLink(const std::string &link,
 
 void ItemLinkHandler::handleHelpLink(const std::string &link)
 {
-    if (helpWindow)
+    if (helpWindow != nullptr)
     {
         helpWindow->loadHelp(link.substr(7));
         helpWindow->requestMoveToTop();
@@ -105,7 +105,7 @@ void ItemLinkHandler::handleHelpLink(const std::string &link)
 void ItemLinkHandler::handleHttpLink(const std::string &link,
                                      const MouseEvent *const event)
 {
-    if (!event)
+    if (event == nullptr)
         return;
     std::string url = link;
     replaceAll(url, " ", "");
@@ -124,14 +124,14 @@ void ItemLinkHandler::handleHttpLink(const std::string &link,
     }
     else if (button == MouseButton::RIGHT)
     {
-        if (popupMenu)
+        if (popupMenu != nullptr)
             popupMenu->showLinkPopup(url);
     }
 }
 
 void ItemLinkHandler::handleItemLink(const std::string &link)
 {
-    if (!itemPopup || link.empty())
+    if ((itemPopup == nullptr) || link.empty())
         return;
 
     const char ch = link[0];
@@ -160,7 +160,7 @@ void ItemLinkHandler::handleItemLink(const std::string &link)
         {
             itemPopup->setVisible(Visible_false);
         }
-        else if (viewport)
+        else if (viewport != nullptr)
         {
             itemPopup->position(viewport->mMouseX,
                 viewport->mMouseY);
@@ -170,7 +170,7 @@ void ItemLinkHandler::handleItemLink(const std::string &link)
 
 void ItemLinkHandler::handleSearchLink(const std::string &link)
 {
-    if (helpWindow)
+    if (helpWindow != nullptr)
     {
         helpWindow->search(link.substr(1));
         helpWindow->requestMoveToTop();
@@ -205,7 +205,7 @@ void ItemLinkHandler::handleLink(const std::string &link,
     }
     else if (link == "news")
     {
-        if (helpWindow)
+        if (helpWindow != nullptr)
             helpWindow->loadHelpSimple("news");
     }
     else if (link == "copyright")
diff --git a/src/gui/widgets/itemshortcutcontainer.cpp b/src/gui/widgets/itemshortcutcontainer.cpp
index 424986efe..400ae0d88 100644
--- a/src/gui/widgets/itemshortcutcontainer.cpp
+++ b/src/gui/widgets/itemshortcutcontainer.cpp
@@ -63,7 +63,7 @@ ItemShortcutContainer::ItemShortcutContainer(Widget2 *const widget,
     mUnEquipedColor(getThemeColor(ThemeColorId::ITEM_NOT_EQUIPPED)),
     mUnEquipedColor2(getThemeColor(ThemeColorId::ITEM_NOT_EQUIPPED_OUTLINE))
 {
-    if (itemShortcut[mNumber])
+    if (itemShortcut[mNumber] != nullptr)
         mMaxItems = itemShortcut[mNumber]->getItemCount();
     else
         mMaxItems = 0;
@@ -88,7 +88,7 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
 {
     BLOCK_START("ItemShortcutContainer::draw")
     const ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
     {
         BLOCK_END("ItemShortcutContainer::draw")
         return;
@@ -96,7 +96,7 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
 
     if (settings.guiAlpha != mAlpha)
     {
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
         mAlpha = settings.guiAlpha;
     }
@@ -105,7 +105,7 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
     drawBackground(graphics);
 
     const Inventory *const inv = PlayerInfo::getInventory();
-    if (!inv)
+    if (inv == nullptr)
     {
         BLOCK_END("ItemShortcutContainer::draw")
         return;
@@ -136,11 +136,11 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
         if (itemId < SPELL_MIN_ID)
         {
             const Item *const item = inv->findItem(itemId, itemColor);
-            if (item)
+            if (item != nullptr)
             {
                 // Draw item icon.
                 Image *const image = item->getImage();
-                if (image)
+                if (image != nullptr)
                 {
                     std::string caption;
                     if (item->getQuantity() > 1)
@@ -171,17 +171,17 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
                 }
             }
         }
-        else if (itemId < SKILL_MIN_ID && spellManager)
+        else if (itemId < SKILL_MIN_ID && (spellManager != nullptr))
         {   // this is magic shortcut
             const TextCommand *const spell = spellManager
                 ->getSpellByItem(itemId);
-            if (spell)
+            if (spell != nullptr)
             {
                 if (!spell->isEmpty())
                 {
                     Image *const image = spell->getImage();
 
-                    if (image)
+                    if (image != nullptr)
                     {
                         image->setAlpha(1.0F);
                         graphics->drawImage(image, itemX, itemY);
@@ -195,15 +195,15 @@ void ItemShortcutContainer::draw(Graphics *const graphics)
                     itemX + 2, itemY + mBoxHeight / 2);
             }
         }
-        else if (skillDialog)
+        else if (skillDialog != nullptr)
         {
             const SkillInfo *const skill = skillDialog->getSkill(
                 itemId - SKILL_MIN_ID);
-            if (skill)
+            if (skill != nullptr)
             {
                 Image *const image = skill->data->icon;
 
-                if (image)
+                if (image != nullptr)
                 {
                     image->setAlpha(1.0F);
                     graphics->drawImage(image, itemX, itemY);
@@ -225,7 +225,7 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("ItemShortcutContainer::draw")
     const ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
     {
         BLOCK_END("ItemShortcutContainer::draw")
         return;
@@ -233,7 +233,7 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
 
     if (settings.guiAlpha != mAlpha)
     {
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
         mAlpha = settings.guiAlpha;
     }
@@ -242,7 +242,7 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
     safeDrawBackground(graphics);
 
     const Inventory *const inv = PlayerInfo::getInventory();
-    if (!inv)
+    if (inv == nullptr)
     {
         BLOCK_END("ItemShortcutContainer::draw")
         return;
@@ -273,11 +273,11 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
         if (itemId < SPELL_MIN_ID)
         {
             const Item *const item = inv->findItem(itemId, itemColor);
-            if (item)
+            if (item != nullptr)
             {
                 // Draw item icon.
                 Image *const image = item->getImage();
-                if (image)
+                if (image != nullptr)
                 {
                     std::string caption;
                     if (item->getQuantity() > 1)
@@ -308,17 +308,17 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
                 }
             }
         }
-        else if (itemId < SKILL_MIN_ID && spellManager)
+        else if (itemId < SKILL_MIN_ID && (spellManager != nullptr))
         {   // this is magic shortcut
             const TextCommand *const spell = spellManager
                 ->getSpellByItem(itemId);
-            if (spell)
+            if (spell != nullptr)
             {
                 if (!spell->isEmpty())
                 {
                     Image *const image = spell->getImage();
 
-                    if (image)
+                    if (image != nullptr)
                     {
                         image->setAlpha(1.0F);
                         graphics->drawImage(image, itemX, itemY);
@@ -332,15 +332,15 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
                     itemX + 2, itemY + mBoxHeight / 2);
             }
         }
-        else if (skillDialog)
+        else if (skillDialog != nullptr)
         {
             const SkillInfo *const skill = skillDialog->getSkill(
                 itemId - SKILL_MIN_ID);
-            if (skill)
+            if (skill != nullptr)
             {
                 Image *const image = skill->data->icon;
 
-                if (image)
+                if (image != nullptr)
                 {
                     image->setAlpha(1.0F);
                     graphics->drawImage(image, itemX, itemY);
@@ -361,7 +361,7 @@ void ItemShortcutContainer::safeDraw(Graphics *const graphics)
 void ItemShortcutContainer::mouseDragged(MouseEvent &event)
 {
     ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
         return;
 
     if (event.getButton() == MouseButton::LEFT)
@@ -383,13 +383,13 @@ void ItemShortcutContainer::mouseDragged(MouseEvent &event)
             event.consume();
             if (itemId < SPELL_MIN_ID)
             {   // items
-                if (!PlayerInfo::getInventory())
+                if (PlayerInfo::getInventory() == nullptr)
                     return;
 
                 const Item *const item = PlayerInfo::getInventory()->findItem(
                     itemId, itemColor);
 
-                if (item)
+                if (item != nullptr)
                 {
                     selShortcut->removeItem(index);
                     dragDrop.dragItem(item, DragDropSource::Shortcuts, index);
@@ -401,7 +401,7 @@ void ItemShortcutContainer::mouseDragged(MouseEvent &event)
             }
             else if (itemId < SKILL_MIN_ID)
             {   // spells/commands
-                if (!spellManager)
+                if (spellManager == nullptr)
                 {
                     dragDrop.clear();
                     return;
@@ -409,7 +409,7 @@ void ItemShortcutContainer::mouseDragged(MouseEvent &event)
 
                 const TextCommand *const spell = spellManager->getSpellByItem(
                     itemId);
-                if (spell)
+                if (spell != nullptr)
                 {
                     selShortcut->removeItem(index);
                     dragDrop.dragCommand(spell,
@@ -423,14 +423,14 @@ void ItemShortcutContainer::mouseDragged(MouseEvent &event)
             }
             else
             {   // skills
-                if (!skillDialog)
+                if (skillDialog == nullptr)
                 {
                     dragDrop.clear();
                     return;
                 }
                 const SkillInfo *const skill
                     = skillDialog->getSkillByItem(itemId);
-                if (skill)
+                if (skill != nullptr)
                 {
                     const std::string itemData = selShortcut->getItemData(
                         index);
@@ -454,7 +454,7 @@ void ItemShortcutContainer::mouseDragged(MouseEvent &event)
 void ItemShortcutContainer::mousePressed(MouseEvent &event)
 {
     ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -466,17 +466,17 @@ void ItemShortcutContainer::mousePressed(MouseEvent &event)
     {
         event.consume();
         // Stores the selected item if theirs one.
-        if (selShortcut->isItemSelected() && inventoryWindow &&
+        if (selShortcut->isItemSelected() && (inventoryWindow != nullptr) &&
             (inventoryWindow->isWindowVisible()
             || selShortcut->getSelectedItem() >= SPELL_MIN_ID))
         {
             selShortcut->setItem(index);
             selShortcut->setItemSelected(-1);
-            if (spellShortcut)
+            if (spellShortcut != nullptr)
                 spellShortcut->setItemSelected(-1);
             inventoryWindow->unselectItem();
         }
-        else if (selShortcut->getItem(index))
+        else if (selShortcut->getItem(index) != 0)
         {
             mItemClicked = true;
         }
@@ -484,7 +484,9 @@ void ItemShortcutContainer::mousePressed(MouseEvent &event)
     else if (event.getButton() == MouseButton::RIGHT)
     {
         event.consume();
-        if (popupMenu && selShortcut && viewport)
+        if (popupMenu != nullptr &&
+            selShortcut != nullptr &&
+            viewport != nullptr)
         {
             popupMenu->showItemPopup(viewport->mMouseX,
                 viewport->mMouseY,
@@ -497,7 +499,7 @@ void ItemShortcutContainer::mousePressed(MouseEvent &event)
 void ItemShortcutContainer::mouseReleased(MouseEvent &event)
 {
     ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
         return;
 
     if (event.getButton() == MouseButton::LEFT)
@@ -511,7 +513,7 @@ void ItemShortcutContainer::mouseReleased(MouseEvent &event)
 
         if (dragDrop.isEmpty())
         {
-            if (selShortcut->getItem(index) && mItemClicked)
+            if ((selShortcut->getItem(index) != 0) && mItemClicked)
                 selShortcut->useItem(index);
         }
         else
@@ -541,7 +543,7 @@ void ItemShortcutContainer::mouseReleased(MouseEvent &event)
 void ItemShortcutContainer::mouseMoved(MouseEvent &event)
 {
     const ItemShortcut *const selShortcut = itemShortcut[mNumber];
-    if (!selShortcut)
+    if (selShortcut == nullptr)
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -561,11 +563,11 @@ void ItemShortcutContainer::mouseMoved(MouseEvent &event)
         spellPopup->setVisible(Visible_false);
 
         Inventory *const inv = PlayerInfo::getInventory();
-        if (!inv)
+        if (inv == nullptr)
             return;
 
         const Item *const item = inv->findItem(itemId, itemColor);
-        if (item && viewport)
+        if ((item != nullptr) && (viewport != nullptr))
         {
             itemPopup->setItem(item, false);
             itemPopup->position(viewport->mMouseX, viewport->mMouseY);
@@ -575,12 +577,12 @@ void ItemShortcutContainer::mouseMoved(MouseEvent &event)
             itemPopup->setVisible(Visible_false);
         }
     }
-    else if (itemId < SKILL_MIN_ID && spellManager)
+    else if (itemId < SKILL_MIN_ID && (spellManager != nullptr))
     {
         skillPopup->setVisible(Visible_false);
         itemPopup->setVisible(Visible_false);
         const TextCommand *const spell = spellManager->getSpellByItem(itemId);
-        if (spell && viewport)
+        if ((spell != nullptr) && (viewport != nullptr))
         {
             spellPopup->setItem(spell);
             spellPopup->view(viewport->mMouseX,
@@ -591,12 +593,12 @@ void ItemShortcutContainer::mouseMoved(MouseEvent &event)
             spellPopup->setVisible(Visible_false);
         }
     }
-    else if (skillDialog)
+    else if (skillDialog != nullptr)
     {
         itemPopup->setVisible(Visible_false);
         spellPopup->setVisible(Visible_false);
         const SkillInfo *const skill = skillDialog->getSkillByItem(itemId);
-        if (!skill)
+        if (skill == nullptr)
             return;
 
         const std::string data = selShortcut->getItemData(index);
@@ -629,18 +631,18 @@ void ItemShortcutContainer::mouseMoved(MouseEvent &event)
 // Hide ItemTooltip
 void ItemShortcutContainer::mouseExited(MouseEvent &event A_UNUSED)
 {
-    if (itemPopup)
+    if (itemPopup != nullptr)
         itemPopup->setVisible(Visible_false);
-    if (spellPopup)
+    if (spellPopup != nullptr)
         spellPopup->setVisible(Visible_false);
-    if (skillPopup)
+    if (skillPopup != nullptr)
         skillPopup->setVisible(Visible_false);
 }
 
 void ItemShortcutContainer::widgetHidden(const Event &event A_UNUSED)
 {
-    if (itemPopup)
+    if (itemPopup != nullptr)
         itemPopup->setVisible(Visible_false);
-    if (spellPopup)
+    if (spellPopup != nullptr)
         spellPopup->setVisible(Visible_false);
 }
diff --git a/src/gui/widgets/label.cpp b/src/gui/widgets/label.cpp
index 52fdbd716..aeacddbdb 100644
--- a/src/gui/widgets/label.cpp
+++ b/src/gui/widgets/label.cpp
@@ -106,16 +106,16 @@ Label::Label(const Widget2 *const widget,
 
 Label::~Label()
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->removeWidgetListener(this);
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     mInstances --;
     if (mInstances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
     }
     removeMouseListener(this);
@@ -130,12 +130,12 @@ void Label::init()
     mForegroundColor2 = getThemeColor(ThemeColorId::LABEL_OUTLINE);
     if (mInstances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             mSkin = theme->load("label.xml", "");
     }
     mInstances ++;
 
-    if (mSkin)
+    if (mSkin != nullptr)
         mPadding = mSkin->getPadding();
     else
         mPadding = 0;
@@ -179,7 +179,7 @@ void Label::draw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, textX, textY);
     BLOCK_END("Label::draw")
 }
@@ -262,14 +262,14 @@ void Label::setCaption(const std::string& caption)
 
 void Label::setParent(Widget *const widget)
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->addWidgetListener(this);
     Widget::setParent(widget);
 }
 
 void Label::setWindow(Widget *const widget)
 {
-    if (!widget && mWindow)
+    if ((widget == nullptr) && (mWindow != nullptr))
     {
         mWindow->removeWidgetListener(this);
         mWindow = nullptr;
diff --git a/src/gui/widgets/layoutarray.cpp b/src/gui/widgets/layoutarray.cpp
index 7bd6ff34f..de9c8cd30 100644
--- a/src/gui/widgets/layoutarray.cpp
+++ b/src/gui/widgets/layoutarray.cpp
@@ -61,15 +61,15 @@ LayoutCell &LayoutArray::at(const int x, const int y,
 {
     resizeGrid(x + w, y + h);
     LayoutCell *&cell = mCells[CAST_SIZE(y)][static_cast<size_t>(x)];
-    if (!cell)
+    if (cell == nullptr)
         cell = new LayoutCell;
     return *cell;
 }
 
 void LayoutArray::resizeGrid(int w, const int h)
 {
-    const bool extW = w && w > CAST_S32(mSizes[0].size());
-    const bool extH = h && h > CAST_S32(mSizes[1].size());
+    const bool extW = (w != 0) && w > CAST_S32(mSizes[0].size());
+    const bool extH = (h != 0) && h > CAST_S32(mSizes[1].size());
 
     if (!extW && !extH)
         return;
@@ -132,7 +132,7 @@ LayoutCell &LayoutArray::place(Widget *const widget, const int x,
     assert(cell.mType == LayoutCell::NONE);
     cell.mType = LayoutCell::WIDGET;
     cell.mWidget = widget;
-    if (widget)
+    if (widget != nullptr)
     {
         cell.mSize[0] = w == 1 ? widget->getWidth() : 0;
         cell.mSize[1] = h == 1 ? widget->getHeight() : 0;
@@ -166,7 +166,7 @@ void LayoutArray::align(int &restrict pos, int &restrict size, const int dim,
         return;
     int size_max = sizes[0];
     int cnt = cell.mExtent[dim];
-    if (sizeCount && cell.mExtent[dim] > sizeCount)
+    if ((sizeCount != 0) && cell.mExtent[dim] > sizeCount)
         cnt = sizeCount;
 
     for (int i = 1; i < cnt; ++i)
@@ -208,7 +208,7 @@ std::vector<int> LayoutArray::getSizes(const int dim, int upp) const
         {
             const LayoutCell *const cell = mCells[CAST_SIZE(gridY)]
                 [CAST_SIZE(gridX)];
-            if (!cell || cell->mType == LayoutCell::NONE)
+            if ((cell == nullptr) || cell->mType == LayoutCell::NONE)
                 continue;
 
             if (cell->mExtent[dim] == 1)
@@ -297,7 +297,7 @@ void LayoutArray::reflow(const int nx, const int ny,
         {
             LayoutCell *const cell = mCells[CAST_SIZE(gridY)]
                 [CAST_SIZE(gridX)];
-            if (cell && cell->mType != LayoutCell::NONE)
+            if ((cell != nullptr) && cell->mType != LayoutCell::NONE)
             {
                 int dx = x, dy = y, dw = 0, dh = 0;
                 align(dx, dw, 0, *cell,
diff --git a/src/gui/widgets/layoutcell.cpp b/src/gui/widgets/layoutcell.cpp
index 21efd4818..b898b1dfc 100644
--- a/src/gui/widgets/layoutcell.cpp
+++ b/src/gui/widgets/layoutcell.cpp
@@ -44,7 +44,7 @@ LayoutArray &LayoutCell::getArray()
         return tempArray;
     if (mType == ARRAY)
     {
-        if (!mArray)
+        if (mArray == nullptr)
             return tempArray;
         return *mArray;
     }
@@ -90,7 +90,7 @@ void LayoutCell::computeSizes()
         while (j != i->end())
         {
             LayoutCell *const cell = *j;
-            if (cell && cell->mType == ARRAY)
+            if ((cell != nullptr) && cell->mType == ARRAY)
                 cell->computeSizes();
 
             ++j;
diff --git a/src/gui/widgets/layouthelper.cpp b/src/gui/widgets/layouthelper.cpp
index 2de26dbab..19114c1ae 100644
--- a/src/gui/widgets/layouthelper.cpp
+++ b/src/gui/widgets/layouthelper.cpp
@@ -32,13 +32,13 @@ LayoutHelper::LayoutHelper(BasicContainer2 *const container) :
     mLayout(),
     mContainer(container)
 {
-    if (mContainer)
+    if (mContainer != nullptr)
         mContainer->addWidgetListener(this);
 }
 
 LayoutHelper::~LayoutHelper()
 {
-    if (mContainer)
+    if (mContainer != nullptr)
         mContainer->removeWidgetListener(this);
 }
 
@@ -51,7 +51,7 @@ LayoutCell &LayoutHelper::place(const int x, const int y,
                                 Widget *const wg,
                                 const int w, const int h)
 {
-    if (mContainer)
+    if (mContainer != nullptr)
         mContainer->add(wg);
     return mLayout.place(wg, x, y, w, h);
 }
@@ -64,13 +64,13 @@ ContainerPlacer LayoutHelper::getPlacer(const int x, const int y)
 void LayoutHelper::reflowLayout(int w, int h)
 {
     mLayout.reflow(w, h);
-    if (mContainer)
+    if (mContainer != nullptr)
         mContainer->setSize(w, h);
 }
 
 void LayoutHelper::widgetResized(const Event &event A_UNUSED)
 {
-    if (!mContainer)
+    if (mContainer == nullptr)
         return;
     const Rect area = mContainer->getChildrenArea();
     int w = area.width;
diff --git a/src/gui/widgets/linepart.cpp b/src/gui/widgets/linepart.cpp
index 0f9403c85..2e1cab392 100644
--- a/src/gui/widgets/linepart.cpp
+++ b/src/gui/widgets/linepart.cpp
@@ -27,7 +27,7 @@
 
 LinePart::~LinePart()
 {
-    if (mImage)
+    if (mImage != nullptr)
         mImage->decRef();
     mImage = nullptr;
 }
diff --git a/src/gui/widgets/listbox.cpp b/src/gui/widgets/listbox.cpp
index 0095baf1f..9628c2764 100644
--- a/src/gui/widgets/listbox.cpp
+++ b/src/gui/widgets/listbox.cpp
@@ -114,10 +114,10 @@ ListBox::ListBox(const Widget2 *const widget,
     mForegroundColor = getThemeColor(ThemeColorId::LISTBOX);
     mForegroundColor2 = getThemeColor(ThemeColorId::LISTBOX_OUTLINE);
 
-    if (theme)
+    if (theme != nullptr)
         mSkin = theme->load(skin, "listbox.xml");
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mPadding = mSkin->getPadding();
         mItemPadding = mSkin->getOption("itemPadding");
@@ -135,10 +135,10 @@ void ListBox::postInit()
 
 ListBox::~ListBox()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
-    if (theme)
+    if (theme != nullptr)
         theme->unload(mSkin);
 }
 
@@ -153,7 +153,7 @@ void ListBox::updateAlpha()
 
 void ListBox::draw(Graphics *const graphics)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return;
 
     BLOCK_START("ListBox::draw")
@@ -245,9 +245,15 @@ void ListBox::keyPressed(KeyEvent &event)
     else if (action == InputAction::GUI_UP)
     {
         if (mSelected > 0)
+        {
             setSelected(mSelected - 1);
-        else if (mSelected == 0 && mWrappingEnabled && getListModel())
+        }
+        else if (mSelected == 0 &&
+                 mWrappingEnabled &&
+                 getListModel() != nullptr)
+        {
             setSelected(getListModel()->getNumberOfElements() - 1);
+        }
         event.consume();
     }
     else if (action == InputAction::GUI_DOWN)
@@ -264,7 +270,7 @@ void ListBox::keyPressed(KeyEvent &event)
         setSelected(0);
         event.consume();
     }
-    else if (action == InputAction::GUI_END && getListModel())
+    else if (action == InputAction::GUI_END && (getListModel() != nullptr))
     {
         setSelected(getListModel()->getNumberOfElements() - 1);
         event.consume();
@@ -311,7 +317,7 @@ void ListBox::mouseReleased(MouseEvent &event)
                 mOldSelected = mSelected;
                 break;
             case 2:
-                if (gui)
+                if (gui != nullptr)
                     gui->resetClickCount();
                 if (mOldSelected == mSelected)
                     mouseReleased1(event);
@@ -343,13 +349,13 @@ void ListBox::mouseDragged(MouseEvent &event)
         return;
 
     // Make list selection update on drag, but guard against negative y
-    if (getRowHeight())
+    if (getRowHeight() != 0u)
         setSelected(std::max(0, getSelectionByMouse(event.getY())));
 }
 
 void ListBox::refocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
 
     if (isFocusable())
@@ -359,7 +365,7 @@ void ListBox::refocus()
 void ListBox::adjustSize()
 {
     BLOCK_START("ListBox::adjustSize")
-    if (mListModel)
+    if (mListModel != nullptr)
     {
         setHeight(CAST_S32(getRowHeight()) *
             mListModel->getNumberOfElements() + 2 * mPadding);
@@ -383,7 +389,7 @@ int ListBox::getSelectionByMouse(const int y) const
 
 void ListBox::setSelected(const int selected)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
     {
         mSelected = -1;
     }
diff --git a/src/gui/widgets/passwordfield.cpp b/src/gui/widgets/passwordfield.cpp
index 7400ffd76..bc2ca4827 100644
--- a/src/gui/widgets/passwordfield.cpp
+++ b/src/gui/widgets/passwordfield.cpp
@@ -29,7 +29,7 @@
 PasswordField::PasswordField(const Widget2 *const widget,
                              const std::string &text) :
     TextField(widget, text),
-    mPasswordChar(mSkin ? CAST_8(
+    mPasswordChar(mSkin != nullptr ? CAST_8(
                   mSkin->getOption("passwordChar", 42))
                   : CAST_8(42))
 {
@@ -40,7 +40,7 @@ void PasswordField::draw(Graphics *const graphics)
     BLOCK_START("PasswordField::draw")
     // std::string uses cow, thus cheap copy
     const std::string original = mText;
-    if (mPasswordChar)
+    if (mPasswordChar != 0)
         mText.assign(mText.length(), mPasswordChar);
     else
         mText.clear();
diff --git a/src/gui/widgets/playerbox.cpp b/src/gui/widgets/playerbox.cpp
index 47221af1f..b6217383f 100644
--- a/src/gui/widgets/playerbox.cpp
+++ b/src/gui/widgets/playerbox.cpp
@@ -76,7 +76,7 @@ PlayerBox::PlayerBox(Widget2 *const widget,
 
 PlayerBox::~PlayerBox()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     Theme::unloadRect(mBackground);
@@ -90,13 +90,13 @@ void PlayerBox::init(std::string name, std::string selectedName)
     setFrameSize(2);
     addMouseListener(this);
 
-    if (theme)
+    if (theme != nullptr)
     {
         if (name.empty())
             name = "playerbox.xml";
         mSkin = theme->loadSkinRect(mBackground,
             name, "playerbox_background.xml");
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             mDrawBackground = (mSkin->getOption("drawbackground") != 0);
             mOffsetX = mSkin->getOption("offsetX", -mapTileSize / 2);
@@ -120,7 +120,7 @@ void PlayerBox::init(std::string name, std::string selectedName)
 void PlayerBox::draw(Graphics *const graphics)
 {
     BLOCK_START("PlayerBox::draw")
-    if (mBeing)
+    if (mBeing != nullptr)
     {
         const int bs = mFrameSize;
         const int x = mDimension.width / 2 + bs + mOffsetX;
@@ -133,7 +133,7 @@ void PlayerBox::draw(Graphics *const graphics)
         const float alpha = settings.guiAlpha;
         for (int a = 0; a < 9; a++)
         {
-            if (mBackground.grid[a])
+            if (mBackground.grid[a] != nullptr)
                 mBackground.grid[a]->setAlpha(alpha);
         }
     }
diff --git a/src/gui/widgets/popup.cpp b/src/gui/widgets/popup.cpp
index 978e5b9ca..bf2b2bb83 100644
--- a/src/gui/widgets/popup.cpp
+++ b/src/gui/widgets/popup.cpp
@@ -60,17 +60,17 @@ Popup::Popup(const std::string &name,
     if (skin.empty())
         skin = "popup.xml";
 
-    if (theme)
+    if (theme != nullptr)
     {
         mSkin = theme->load(skin, "popup.xml");
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             setPadding(mSkin->getPadding());
             setPalette(mSkin->getOption("palette"));
         }
     }
 
-    if (windowContainer)
+    if (windowContainer != nullptr)
         windowContainer->add(this);
 
     // Popups are invisible by default
@@ -83,9 +83,9 @@ Popup::~Popup()
 
     delete2(mVertexes);
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
         mSkin = nullptr;
     }
@@ -106,7 +106,7 @@ void Popup::draw(Graphics *const graphics)
 {
     BLOCK_START("Popup::draw")
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         if (mRedraw)
         {
@@ -130,7 +130,7 @@ void Popup::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("Popup::safeDraw")
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         graphics->drawImageRect(0, 0,
             mDimension.width, mDimension.height,
@@ -169,7 +169,7 @@ void Popup::setContentSize(int width, int height)
 
 void Popup::setLocationRelativeTo(const Widget *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     int wx, wy;
@@ -187,7 +187,7 @@ void Popup::setLocationRelativeTo(const Widget *const widget)
 
 void Popup::setMinWidth(const int width)
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mMinWidth = width > mSkin->getMinWidth()
             ? width : mSkin->getMinWidth();
@@ -200,7 +200,7 @@ void Popup::setMinWidth(const int width)
 
 void Popup::setMinHeight(const int height)
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mMinHeight = height > mSkin->getMinHeight() ?
             height : mSkin->getMinHeight();
@@ -248,7 +248,7 @@ void Popup::position(const int x, const int y)
 
 void Popup::mouseMoved(MouseEvent &event A_UNUSED)
 {
-    if (popupManager)
+    if (popupManager != nullptr)
     {
         popupManager->hideBeingPopup();
         popupManager->hideTextPopup();
diff --git a/src/gui/widgets/popuplist.cpp b/src/gui/widgets/popuplist.cpp
index d623fd811..0260945ce 100644
--- a/src/gui/widgets/popuplist.cpp
+++ b/src/gui/widgets/popuplist.cpp
@@ -61,7 +61,7 @@ void PopupList::postInit()
     Popup::postInit();
     add(mScrollArea);
 
-    if (gui)
+    if (gui != nullptr)
         gui->addGlobalFocusListener(this);
 
     addKeyListener(mDropDown);
@@ -71,9 +71,9 @@ void PopupList::postInit()
 
 PopupList::~PopupList()
 {
-    if (mParent)
+    if (mParent != nullptr)
         mParent->removeFocusListener(this);
-    if (gui)
+    if (gui != nullptr)
         gui->removeGlobalFocusListener(this);
     removeKeyListener(mDropDown);
 }
@@ -105,7 +105,7 @@ void PopupList::widgetResized(const Event &event)
 
 void PopupList::setSelected(const int selected)
 {
-    if (!mListBox)
+    if (mListBox == nullptr)
         return;
 
     mListBox->setSelected(selected);
@@ -113,7 +113,7 @@ void PopupList::setSelected(const int selected)
 
 int PopupList::getSelected() const
 {
-    if (!mListBox)
+    if (mListBox == nullptr)
         return -1;
 
     return mListBox->getSelected();
@@ -121,7 +121,7 @@ int PopupList::getSelected() const
 
 void PopupList::setListModel(ListModel *const model)
 {
-    if (mListBox)
+    if (mListBox != nullptr)
         mListBox->setListModel(model);
     mListModel = model;
 }
@@ -155,7 +155,7 @@ void PopupList::mouseReleased(MouseEvent& event)
     mPressedIndex = -2;
     if (event.getSource() == mScrollArea)
         return;
-    if (mDropDown)
+    if (mDropDown != nullptr)
         mDropDown->updateSelection();
     setVisible(Visible_false);
     if (mModal == Modal_true)
@@ -174,7 +174,7 @@ void PopupList::focusGained(const Event& event)
         return;
     }
 
-    if (mDropDown)
+    if (mDropDown != nullptr)
         mDropDown->updateSelection();
     setVisible(Visible_false);
     if (mModal == Modal_true)
@@ -183,6 +183,6 @@ void PopupList::focusGained(const Event& event)
 
 void PopupList::focusLost(const Event& event A_UNUSED)
 {
-    if (mDropDown)
+    if (mDropDown != nullptr)
         mDropDown->updateSelection();
 }
diff --git a/src/gui/widgets/progressbar.cpp b/src/gui/widgets/progressbar.cpp
index e84200973..7299140c6 100644
--- a/src/gui/widgets/progressbar.cpp
+++ b/src/gui/widgets/progressbar.cpp
@@ -80,10 +80,10 @@ ProgressBar::ProgressBar(const Widget2 *const widget,
     addWidgetListener(this);
     setSize(width, height);
 
-    if (theme)
+    if (theme != nullptr)
     {
         mSkin = theme->load(skin, "progressbar.xml");
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             setPadding(mSkin->getPadding());
             mFillPadding = mSkin->getOption("fillPadding");
@@ -99,13 +99,13 @@ ProgressBar::ProgressBar(const Widget2 *const widget,
 
 ProgressBar::~ProgressBar()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     mInstances--;
-    if (mSkin)
+    if (mSkin != nullptr)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
         mSkin = nullptr;
     }
@@ -157,7 +157,7 @@ void ProgressBar::updateAlpha()
 void ProgressBar::draw(Graphics *const graphics)
 {
     BLOCK_START("ProgressBar::draw")
-    if (!mSkin)
+    if (mSkin == nullptr)
     {
         BLOCK_END("ProgressBar::draw")
         return;
@@ -223,7 +223,7 @@ void ProgressBar::draw(Graphics *const graphics)
         }
 
         const Image *const image = mTextChunk.img;
-        if (image)
+        if (image != nullptr)
         {
             const int textX = (mDimension.width - font->getWidth(mText)) / 2;
             const int textY = (mDimension.height - font->getHeight()) / 2;
@@ -236,7 +236,7 @@ void ProgressBar::draw(Graphics *const graphics)
 void ProgressBar::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("ProgressBar::safeDraw")
-    if (!mSkin)
+    if (mSkin == nullptr)
     {
         BLOCK_END("ProgressBar::safeDraw")
         return;
@@ -294,7 +294,7 @@ void ProgressBar::safeDraw(Graphics *const graphics)
         }
 
         const Image *const image = mTextChunk.img;
-        if (image)
+        if (image != nullptr)
         {
             const int textX = (mDimension.width - font->getWidth(mText)) / 2;
             const int textY = (mDimension.height - font->getHeight()) / 2;
diff --git a/src/gui/widgets/progressindicator.cpp b/src/gui/widgets/progressindicator.cpp
index 1b2b333e2..abeee678c 100644
--- a/src/gui/widgets/progressindicator.cpp
+++ b/src/gui/widgets/progressindicator.cpp
@@ -39,7 +39,7 @@ ProgressIndicator::ProgressIndicator(const Widget2 *const widget) :
     ImageSet *const images = Theme::getImageSetFromTheme(
         "progress-indicator.png", 32, 32);
 
-    if (images)
+    if (images != nullptr)
     {
         Animation *const anim = new Animation("progress indicator");
         for (ImageSet::size_type i = 0, fsz = images->size();
@@ -57,7 +57,7 @@ ProgressIndicator::ProgressIndicator(const Widget2 *const widget) :
 
 ProgressIndicator::~ProgressIndicator()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     delete2(mIndicator);
@@ -66,7 +66,7 @@ ProgressIndicator::~ProgressIndicator()
 void ProgressIndicator::logic()
 {
     BLOCK_START("ProgressIndicator::logic")
-    if (mIndicator)
+    if (mIndicator != nullptr)
         mIndicator->update(10);
     BLOCK_END("ProgressIndicator::logic")
 }
@@ -74,7 +74,7 @@ void ProgressIndicator::logic()
 void ProgressIndicator::draw(Graphics *const graphics)
 {
     BLOCK_START("ProgressIndicator::draw")
-    if (mIndicator)
+    if (mIndicator != nullptr)
     {
         // Draw the indicator centered on the widget
         const int x = (mDimension.width - 32) / 2;
@@ -87,7 +87,7 @@ void ProgressIndicator::draw(Graphics *const graphics)
 void ProgressIndicator::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("ProgressIndicator::draw")
-    if (mIndicator)
+    if (mIndicator != nullptr)
     {
         // Draw the indicator centered on the widget
         const int x = (mDimension.width - 32) / 2;
diff --git a/src/gui/widgets/radiobutton.cpp b/src/gui/widgets/radiobutton.cpp
index 3a781061c..71b7171ae 100644
--- a/src/gui/widgets/radiobutton.cpp
+++ b/src/gui/widgets/radiobutton.cpp
@@ -119,7 +119,7 @@ RadioButton::RadioButton(const Widget2 *const widget,
     mForegroundColor2 = getThemeColor(ThemeColorId::RADIOBUTTON_OUTLINE);
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             mSkin = theme->load("radio.xml", "");
             updateAlpha();
@@ -128,7 +128,7 @@ RadioButton::RadioButton(const Widget2 *const widget,
 
     instances++;
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mPadding = mSkin->getPadding();
         mImagePadding = mSkin->getOption("imagePadding");
@@ -142,19 +142,19 @@ RadioButton::RadioButton(const Widget2 *const widget,
 
 RadioButton::~RadioButton()
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->removeWidgetListener(this);
 
     setGroup(std::string());
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     instances--;
 
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
     }
 }
@@ -167,13 +167,13 @@ void RadioButton::updateAlpha()
     if (mAlpha != alpha)
     {
         mAlpha = alpha;
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             const ImageRect &rect = mSkin->getBorder();
             for (int a = 0; a < 4; a ++)
             {
                 Image *const image = rect.grid[a];
-                if (image)
+                if (image != nullptr)
                     image->setAlpha(mAlpha);
             }
         }
@@ -182,7 +182,7 @@ void RadioButton::updateAlpha()
 
 void RadioButton::drawBox(Graphics *const graphics)
 {
-    if (!mSkin)
+    if (mSkin == nullptr)
         return;
 
     const ImageRect &rect = mSkin->getBorder();
@@ -217,7 +217,7 @@ void RadioButton::drawBox(Graphics *const graphics)
 
     updateAlpha();
 
-    if (box)
+    if (box != nullptr)
     {
         graphics->drawImage(box,
             mImagePadding,
@@ -244,7 +244,7 @@ void RadioButton::draw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, mTextX, mPadding);
 
     BLOCK_END("RadioButton::draw")
@@ -293,7 +293,7 @@ void RadioButton::setSelected(const bool selected)
              iter != iterEnd;
              ++ iter)
         {
-            if (iter->second && iter->second->isSelected())
+            if ((iter->second != nullptr) && iter->second->isSelected())
                 iter->second->setSelected(false);
         }
     }
@@ -348,7 +348,7 @@ void RadioButton::setCaption(const std::string& caption)
 
 void RadioButton::setParent(Widget *widget)
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->addWidgetListener(this);
     Widget::setParent(widget);
 }
@@ -361,7 +361,7 @@ void RadioButton::widgetHidden(const Event &event A_UNUSED)
 
 void RadioButton::setWindow(Widget *const widget)
 {
-    if (!widget && mWindow)
+    if ((widget == nullptr) && (mWindow != nullptr))
     {
         mWindow->removeWidgetListener(this);
         mWindow = nullptr;
diff --git a/src/gui/widgets/scrollarea.cpp b/src/gui/widgets/scrollarea.cpp
index 4ac8f5dce..630f7e9bf 100644
--- a/src/gui/widgets/scrollarea.cpp
+++ b/src/gui/widgets/scrollarea.cpp
@@ -148,7 +148,7 @@ ScrollArea::ScrollArea(Widget2 *const widget2,
 
 ScrollArea::~ScrollArea()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     // Garbage collection
@@ -166,7 +166,7 @@ ScrollArea::~ScrollArea()
         {
             for (int f = UP; f < BUTTONS_DIR; f ++)
             {
-                if (buttons[f][i])
+                if (buttons[f][i] != nullptr)
                     buttons[f][i]->decRef();
             }
         }
@@ -201,7 +201,7 @@ void ScrollArea::init(std::string skinName)
         // +++ here probably need move background from static
         if (skinName.empty())
             skinName = "scroll_background.xml";
-        if (theme)
+        if (theme != nullptr)
         {
             theme->loadRect(background, skinName, "scroll_background.xml");
             theme->loadRect(vMarker, "scroll.xml", "");
@@ -213,14 +213,14 @@ void ScrollArea::init(std::string skinName)
         for (int i = 0; i < 2; i ++)
         {
             Skin *skin = nullptr;
-            if (theme)
+            if (theme != nullptr)
                 skin = theme->load(buttonFiles[i], "scrollbuttons.xml");
-            if (skin)
+            if (skin != nullptr)
             {
                 const ImageRect &rect = skin->getBorder();
                 for (int f = UP; f < BUTTONS_DIR; f ++)
                 {
-                    if (rect.grid[f])
+                    if (rect.grid[f] != nullptr)
                         rect.grid[f]->incRef();
                     buttons[f][i] = rect.grid[f];
                 }
@@ -236,7 +236,7 @@ void ScrollArea::init(std::string skinName)
                 for (int f = UP; f < BUTTONS_DIR; f ++)
                     buttons[f][i] = nullptr;
             }
-            if (theme)
+            if (theme != nullptr)
                 theme->unload(skin);
         }
     }
@@ -259,7 +259,7 @@ void ScrollArea::logic()
     setHorizontalScrollAmount(getHorizontalScrollAmount());
 
     Widget *const content = getContent();
-    if (content)
+    if (content != nullptr)
     {
         unsigned int frameSize = content->getFrameSize();
         content->setPosition(-mHScroll + frameSize, -mVScroll + frameSize);
@@ -301,15 +301,15 @@ void ScrollArea::updateAlpha()
         mAlpha = alpha;
         for (int a = 0; a < 9; a++)
         {
-            if (background.grid[a])
+            if (background.grid[a] != nullptr)
                 background.grid[a]->setAlpha(mAlpha);
-            if (hBackground.grid[a])
+            if (hBackground.grid[a] != nullptr)
                 hBackground.grid[a]->setAlpha(mAlpha);
-            if (vBackground.grid[a])
+            if (vBackground.grid[a] != nullptr)
                 vBackground.grid[a]->setAlpha(mAlpha);
-            if (vMarker.grid[a])
+            if (vMarker.grid[a] != nullptr)
                 vMarker.grid[a]->setAlpha(mAlpha);
-            if (vMarkerHi.grid[a])
+            if (vMarkerHi.grid[a] != nullptr)
                 vMarkerHi.grid[a]->setAlpha(mAlpha);
         }
     }
@@ -512,7 +512,7 @@ void ScrollArea::drawButton(Graphics *const graphics,
     Rect dim;
     const Image *const image = getImageByState(dim, dir);
 
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, dim.x, dim.y);
 }
 
@@ -522,7 +522,7 @@ void ScrollArea::calcButton(Graphics *const graphics,
     Rect dim;
     const Image *const image = getImageByState(dim, dir);
 
-    if (image)
+    if (image != nullptr)
     {
         static_cast<Graphics*>(graphics)->calcTileCollection(
             mVertexes, image, dim.x, dim.y);
@@ -533,18 +533,18 @@ void ScrollArea::drawVBar(Graphics *const graphics) const
 {
     const Rect &dim = getVerticalBarDimension();
 
-    if (vBackground.grid[4])
+    if (vBackground.grid[4] != nullptr)
     {
         graphics->drawPattern(vBackground.grid[4],
             dim.x, dim.y, dim.width, dim.height);
     }
-    if (vBackground.grid[1])
+    if (vBackground.grid[1] != nullptr)
     {
         graphics->drawPattern(vBackground.grid[1],
             dim.x, dim.y,
             dim.width, vBackground.grid[1]->getHeight());
     }
-    if (vBackground.grid[7])
+    if (vBackground.grid[7] != nullptr)
     {
         graphics->drawPattern(vBackground.grid[7],
             dim.x, dim.height - vBackground.grid[7]->getHeight() + dim.y,
@@ -556,21 +556,21 @@ void ScrollArea::calcVBar(const Graphics *const graphics)
 {
     const Rect &dim = getVerticalBarDimension();
 
-    if (vBackground.grid[4])
+    if (vBackground.grid[4] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             vBackground.grid[4],
             dim.x, dim.y,
             dim.width, dim.height);
     }
-    if (vBackground.grid[1])
+    if (vBackground.grid[1] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             vBackground.grid[1],
             dim.x, dim.y,
             dim.width, vBackground.grid[1]->getHeight());
     }
-    if (vBackground.grid[7])
+    if (vBackground.grid[7] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             vBackground.grid[7],
@@ -583,21 +583,21 @@ void ScrollArea::drawHBar(Graphics *const graphics) const
 {
     const Rect &dim = getHorizontalBarDimension();
 
-    if (hBackground.grid[4])
+    if (hBackground.grid[4] != nullptr)
     {
         graphics->drawPattern(hBackground.grid[4],
             dim.x, dim.y,
             dim.width, dim.height);
     }
 
-    if (hBackground.grid[3])
+    if (hBackground.grid[3] != nullptr)
     {
         graphics->drawPattern(hBackground.grid[3],
             dim.x, dim.y,
             hBackground.grid[3]->getWidth(), dim.height);
     }
 
-    if (hBackground.grid[5])
+    if (hBackground.grid[5] != nullptr)
     {
         graphics->drawPattern(hBackground.grid[5],
             dim.x + dim.width - hBackground.grid[5]->getWidth(),
@@ -611,7 +611,7 @@ void ScrollArea::calcHBar(const Graphics *const graphics)
 {
     const Rect &dim = getHorizontalBarDimension();
 
-    if (hBackground.grid[4])
+    if (hBackground.grid[4] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             hBackground.grid[4],
@@ -619,7 +619,7 @@ void ScrollArea::calcHBar(const Graphics *const graphics)
             dim.width, dim.height);
     }
 
-    if (hBackground.grid[3])
+    if (hBackground.grid[3] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             hBackground.grid[3],
@@ -627,7 +627,7 @@ void ScrollArea::calcHBar(const Graphics *const graphics)
             hBackground.grid[3]->getWidth(), dim.height);
     }
 
-    if (hBackground.grid[5])
+    if (hBackground.grid[5] != nullptr)
     {
         graphics->calcPattern(mVertexes,
             hBackground.grid[5],
@@ -736,7 +736,7 @@ void ScrollArea::widgetResized(const Event &event A_UNUSED)
     mRedraw = true;
     const unsigned int frameSize = 2 * mFrameSize;
     Widget *const content = getContent();
-    if (content)
+    if (content != nullptr)
     {
         content->setSize(mDimension.width - frameSize,
             mDimension.height - frameSize);
@@ -834,7 +834,9 @@ void ScrollArea::mousePressed(MouseEvent& event)
 
 void ScrollArea::mouseReleased(MouseEvent& event)
 {
-    if (event.getButton() == MouseButton::LEFT && mClickX && mClickY)
+    if (event.getButton() == MouseButton::LEFT &&
+        mClickX != 0 &&
+        mClickY != 0)
     {
         if (!event.isConsumed())
         {
@@ -869,7 +871,7 @@ void ScrollArea::mouseReleased(MouseEvent& event)
 
                 setHorizontalScrollAmount(s);
             }
-            else if (dy)
+            else if (dy != 0)
             {
                 int s = mVScroll + dy;
                 if (s < 0)
@@ -887,7 +889,7 @@ void ScrollArea::mouseReleased(MouseEvent& event)
             }
             mClickX = 0;
             mClickY = 0;
-            if (mMouseConsume && (dx || dy))
+            if (mMouseConsume && ((dx != 0) || (dy != 0)))
                 event.consume();
         }
     }
@@ -1007,17 +1009,17 @@ Rect ScrollArea::getVerticalMarkerDimension()
         height = mDimension.height - 2 * h2;
 
     const int maxV = getVerticalMaxScroll();
-    if (mMarkerSize && maxV)
+    if ((mMarkerSize != 0) && (maxV != 0))
     {
         pos = (mVScroll * height / maxV - mMarkerSize / 2);
         length = mMarkerSize;
     }
     else
     {
-        if (content)
+        if (content != nullptr)
         {
             const int h3 = content->getHeight();
-            if (h3)
+            if (h3 != 0)
                 length = (height * getChildrenArea().height) / h3;
             else
                 length = height;
@@ -1065,17 +1067,17 @@ Rect ScrollArea::getHorizontalMarkerDimension()
         width = mDimension.width - w2 - mScrollbarWidth;
 
     const int maxH = getHorizontalMaxScroll();
-    if (mMarkerSize && maxH)
+    if ((mMarkerSize != 0) && (maxH != 0))
     {
         pos = (mHScroll * width / maxH - mMarkerSize / 2);
         length = mMarkerSize;
     }
     else
     {
-        if (content)
+        if (content != nullptr)
         {
             const int w3 = content->getWidth();
-            if (w3)
+            if (w3 != 0)
                 length = (width * getChildrenArea().width) / w3;
             else
                 length = width;
@@ -1164,7 +1166,7 @@ Rect ScrollArea::getRightButtonDimension() const
 
 void ScrollArea::setContent(Widget* widget)
 {
-    if (widget)
+    if (widget != nullptr)
     {
         clear();
         add(widget);
@@ -1242,7 +1244,7 @@ int ScrollArea::getHorizontalMaxScroll()
     checkPolicies();
 
     const Widget *const content = getContent();
-    if (!content)
+    if (content == nullptr)
         return 0;
 
     const int value = content->getWidth() - getChildrenArea().width +
@@ -1259,7 +1261,7 @@ int ScrollArea::getVerticalMaxScroll()
     checkPolicies();
 
     const Widget *const content = getContent();
-    if (!content)
+    if (content == nullptr)
         return 0;
 
     int value;
@@ -1282,7 +1284,7 @@ void ScrollArea::setScrollbarWidth(const int width)
 void ScrollArea::showWidgetPart(Widget *const widget, const Rect &area)
 {
     const Widget *const content = getContent();
-    if (widget != content || !content)
+    if (widget != content || (content == nullptr))
         return;
 
     BasicContainer::showWidgetPart(widget, area);
@@ -1362,7 +1364,7 @@ void ScrollArea::checkPolicies()
     mVBarVisible = false;
 
     const Widget *const content = getContent();
-    if (!content)
+    if (content == nullptr)
     {
         mHBarVisible = (mHPolicy == SHOW_ALWAYS);
         mVBarVisible = (mVPolicy == SHOW_ALWAYS);
diff --git a/src/gui/widgets/selldialog.cpp b/src/gui/widgets/selldialog.cpp
index b455597a2..fc7bd9701 100644
--- a/src/gui/widgets/selldialog.cpp
+++ b/src/gui/widgets/selldialog.cpp
@@ -87,7 +87,7 @@ void SellDialog::postInit()
     setMinHeight(220);
     setDefaultSize(260, 230, ImagePosition::CENTER);
 
-    if (setupWindow)
+    if (setupWindow != nullptr)
         setupWindow->registerWindowForReset(this);
 
     // Create a ShopItems instance, that is aware of duplicate entries.
@@ -205,7 +205,7 @@ SellDialog::~SellDialog()
 void SellDialog::reset()
 {
     mShopItems->clear();
-    if (mSlider)
+    if (mSlider != nullptr)
         mSlider->setValue(0);
     mShopItemList->setSelected(-1);
     updateButtonsAndLabels();
@@ -213,7 +213,7 @@ void SellDialog::reset()
 
 void SellDialog::addItem(const Item *const item, const int price)
 {
-    if (!item)
+    if (item == nullptr)
         return;
 
     mShopItems->addItem2(item->getInvIndex(),
@@ -263,25 +263,30 @@ void SellDialog::action(const ActionEvent &event)
 
     if (eventId == "slider")
     {
-        if (mSlider)
+        if (mSlider != nullptr)
         {
             mAmountItems = CAST_S32(mSlider->getValue());
             updateButtonsAndLabels();
         }
     }
-    else if (eventId == "inc" && mSlider && mAmountItems < mMaxItems)
+    else if (eventId == "inc" &&
+             mSlider != nullptr &&
+             mAmountItems < mMaxItems)
     {
         mAmountItems++;
         mSlider->setValue(mAmountItems);
         updateButtonsAndLabels();
     }
-    else if (eventId == "dec" && mSlider && mAmountItems > 1)
+    else if (eventId == "dec" &&
+             mSlider != nullptr &&
+             mAmountItems > 1)
     {
         mAmountItems--;
         mSlider->setValue(mAmountItems);
         updateButtonsAndLabels();
     }
-    else if (eventId == "max" && mSlider)
+    else if (eventId == "max" &&
+             mSlider != nullptr)
     {
         mAmountItems = mMaxItems;
         mSlider->setValue(mAmountItems);
@@ -300,7 +305,7 @@ void SellDialog::valueChanged(const SelectionEvent &event A_UNUSED)
 {
     // Reset amount of items and update labels
     mAmountItems = 1;
-    if (mSlider)
+    if (mSlider != nullptr)
     {
         mSlider->setValue(0);
         mSlider->setScale(1, mMaxItems);
@@ -320,10 +325,10 @@ void SellDialog::updateButtonsAndLabels()
     int income = 0;
     ShopItem *item = nullptr;
 
-    if (selectedItem > -1 && mShopItems->at(selectedItem))
+    if (selectedItem > -1 && (mShopItems->at(selectedItem) != nullptr))
     {
         item = mShopItems->at(selectedItem);
-        if (item)
+        if (item != nullptr)
         {
             mMaxItems = item->getQuantity();
             if (mAmountItems > mMaxItems)
@@ -344,27 +349,27 @@ void SellDialog::updateButtonsAndLabels()
 
     // Update Buttons and slider
     mSellButton->setEnabled(mAmountItems > 0);
-    if (mDecreaseButton)
+    if (mDecreaseButton != nullptr)
         mDecreaseButton->setEnabled(mAmountItems > 1);
-    if (mIncreaseButton)
+    if (mIncreaseButton != nullptr)
         mIncreaseButton->setEnabled(mAmountItems < mMaxItems);
-    if (mSlider)
+    if (mSlider != nullptr)
         mSlider->setEnabled(mMaxItems > 1);
 
-    if (mQuantityLabel)
+    if (mQuantityLabel != nullptr)
     {
         // Update the quantity and money labels
         mQuantityLabel->setCaption(strprintf("%d / %d",
             mAmountItems, mMaxItems));
     }
-    if (mMoneyLabel)
+    if (mMoneyLabel != nullptr)
     {
         // TRANSLATORS: sell dialog label
         mMoneyLabel->setCaption(strprintf(_("Price: %s / Total: %s"),
             UnitsDb::formatCurrency(income).c_str(),
             UnitsDb::formatCurrency(mPlayerMoney + income).c_str()));
     }
-    if (item)
+    if (item != nullptr)
         item->update();
 }
 
@@ -374,7 +379,7 @@ void SellDialog::setVisible(Visible visible)
 
     if (visible == Visible_true)
     {
-        if (mShopItemList)
+        if (mShopItemList != nullptr)
             mShopItemList->requestFocus();
     }
     else
diff --git a/src/gui/widgets/serverslistbox.h b/src/gui/widgets/serverslistbox.h
index fb45dd01a..20d019f8d 100644
--- a/src/gui/widgets/serverslistbox.h
+++ b/src/gui/widgets/serverslistbox.h
@@ -47,7 +47,7 @@ class ServersListBox final : public ListBox
 
         void draw(Graphics *const graphics) override final A_NONNULL(2)
         {
-            if (!mListModel)
+            if (mListModel == nullptr)
                 return;
 
             ServersListModel *const model
diff --git a/src/gui/widgets/setupitem.cpp b/src/gui/widgets/setupitem.cpp
index 2ebd2ef19..8d6296d52 100644
--- a/src/gui/widgets/setupitem.cpp
+++ b/src/gui/widgets/setupitem.cpp
@@ -151,7 +151,7 @@ void SetupItem::save()
 
 std::string SetupItem::getActionEventId() const
 {
-    if (!mWidget)
+    if (mWidget == nullptr)
         return std::string();
 
     return mWidget->getActionEventId();
@@ -159,7 +159,7 @@ std::string SetupItem::getActionEventId() const
 
 void SetupItem::action(const ActionEvent &event)
 {
-    if (!mWidget)
+    if (mWidget == nullptr)
         return;
 
     if (event.getId() == mWidget->getActionEventId())
@@ -194,7 +194,7 @@ void SetupItem::externalUnloaded(const std::string &eventName A_UNUSED)
 
 void SetupItem::fixFirstItemSize(Widget *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     const int maxSize = mParent->getPreferredFirstItemSize();
     if (widget->getWidth() < maxSize)
@@ -251,7 +251,7 @@ void SetupItemCheckBox::createControls()
 
 void SetupItemCheckBox::fromWidget()
 {
-    if (!mCheckBox)
+    if (mCheckBox == nullptr)
         return;
 
     if (mCheckBox->isSelected())
@@ -262,7 +262,7 @@ void SetupItemCheckBox::fromWidget()
 
 void SetupItemCheckBox::toWidget()
 {
-    if (!mCheckBox)
+    if (mCheckBox == nullptr)
         return;
 
     mCheckBox->setSelected(mValue != "0");
@@ -390,7 +390,7 @@ void SetupItemTextField::createControls()
 
 void SetupItemTextField::fromWidget()
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     mValue = mTextField->getText();
@@ -398,7 +398,7 @@ void SetupItemTextField::fromWidget()
 
 void SetupItemTextField::toWidget()
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     mTextField->setText(mValue);
@@ -406,11 +406,11 @@ void SetupItemTextField::toWidget()
 
 void SetupItemTextField::action(const ActionEvent &event)
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     const std::string &eventId = event.getId();
-    if (mWidget && eventId == mWidget->getActionEventId())
+    if ((mWidget != nullptr) && eventId == mWidget->getActionEventId())
     {
         fromWidget();
     }
@@ -528,7 +528,7 @@ void SetupItemIntTextField::createControls()
 
 void SetupItemIntTextField::fromWidget()
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     mValue = mTextField->getText();
@@ -536,7 +536,7 @@ void SetupItemIntTextField::fromWidget()
 
 void SetupItemIntTextField::toWidget()
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     mTextField->setText(mValue);
@@ -544,11 +544,11 @@ void SetupItemIntTextField::toWidget()
 
 void SetupItemIntTextField::action(const ActionEvent &event)
 {
-    if (!mTextField)
+    if (mTextField == nullptr)
         return;
 
     const std::string &eventId = event.getId();
-    if (mWidget && eventId == mWidget->getActionEventId())
+    if ((mWidget != nullptr) && eventId == mWidget->getActionEventId())
     {
         fromWidget();
     }
@@ -708,7 +708,7 @@ void SetupItemDropDown::createControls()
 
 void SetupItemDropDown::fromWidget()
 {
-    if (!mDropDown)
+    if (mDropDown == nullptr)
         return;
 
     mValue = toString(mDropDown->getSelected());
@@ -716,7 +716,7 @@ void SetupItemDropDown::fromWidget()
 
 void SetupItemDropDown::toWidget()
 {
-    if (!mDropDown)
+    if (mDropDown == nullptr)
         return;
 
     mDropDown->setSelected(atoi(mValue.c_str()));
@@ -810,7 +810,7 @@ void SetupItemSlider::createControls()
 
 void SetupItemSlider::fromWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mValue = toString(mSlider->getValue());
@@ -818,7 +818,7 @@ void SetupItemSlider::fromWidget()
 
 void SetupItemSlider::toWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mSlider->setValue(atof(mValue.c_str()));
@@ -945,7 +945,7 @@ void SetupItemSlider2::createControls()
 
 int SetupItemSlider2::getMaxWidth()
 {
-    if (!mValues || !gui)
+    if ((mValues == nullptr) || (gui == nullptr))
         return 1;
 
     int maxWidth = 0;
@@ -966,7 +966,7 @@ int SetupItemSlider2::getMaxWidth()
 
 void SetupItemSlider2::fromWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     int val = roundDouble(mSlider->getValue());
@@ -977,7 +977,7 @@ void SetupItemSlider2::fromWidget()
 
 void SetupItemSlider2::toWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     int val = roundDouble(atof(mValue.c_str()));
@@ -1107,7 +1107,7 @@ void SetupItemSliderList::createControls()
 
 void SetupItemSliderList::fromWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mValue = mSlider->getSelectedString();
@@ -1115,7 +1115,7 @@ void SetupItemSliderList::fromWidget()
 
 void SetupItemSliderList::toWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mSlider->setSelectedString(mValue);
@@ -1157,7 +1157,7 @@ void SetupItemSound::addMoreControls()
 {
     mButton = new Button(this, BUTTON_PLAY, 16, 16,
         mEventName + "_PLAY", this);
-    if (mHorizont)
+    if (mHorizont != nullptr)
         mHorizont->add(mButton);
 }
 
@@ -1165,7 +1165,7 @@ void SetupItemSound::action(const ActionEvent &event)
 {
     if (event.getId() == mEventName + "_PLAY")
     {
-        if (mSlider && mSlider->getSelected())
+        if ((mSlider != nullptr) && (mSlider->getSelected() != 0))
         {
             soundManager.playGuiSfx(pathJoin(branding.getStringValue(
                 "systemsounds"),
@@ -1202,7 +1202,7 @@ void SetupItemSliderInt::addMoreControls()
 
 void SetupItemSliderInt::fromWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mValue = toString(mSlider->getSelected() + mMin);
@@ -1210,7 +1210,7 @@ void SetupItemSliderInt::fromWidget()
 
 void SetupItemSliderInt::toWidget()
 {
-    if (!mSlider)
+    if (mSlider == nullptr)
         return;
 
     mSlider->setSelected(atoi(mValue.c_str()) - mMin);
diff --git a/src/gui/widgets/setuptouchitem.cpp b/src/gui/widgets/setuptouchitem.cpp
index 8dbaf550f..122853c7e 100644
--- a/src/gui/widgets/setuptouchitem.cpp
+++ b/src/gui/widgets/setuptouchitem.cpp
@@ -87,7 +87,7 @@ SetupActionDropDown::~SetupActionDropDown()
 
 void SetupActionDropDown::createControls()
 {
-    if (!mModel)
+    if (mModel == nullptr)
         return;
 
     load();
@@ -115,7 +115,7 @@ void SetupActionDropDown::createControls()
 
 void SetupActionDropDown::fromWidget()
 {
-    if (!mDropDown || !mModel)
+    if ((mDropDown == nullptr) || (mModel == nullptr))
         return;
 
     mValue = toString(CAST_S32(mModel->getActionFromSelection(
@@ -124,7 +124,7 @@ void SetupActionDropDown::fromWidget()
 
 void SetupActionDropDown::toWidget()
 {
-    if (!mDropDown || !mModel)
+    if ((mDropDown == nullptr) || (mModel == nullptr))
         return;
 
     mDropDown->setSelected(mModel->getSelectionFromAction(
diff --git a/src/gui/widgets/shoplistbox.cpp b/src/gui/widgets/shoplistbox.cpp
index f1e5ed32f..3df46b854 100644
--- a/src/gui/widgets/shoplistbox.cpp
+++ b/src/gui/widgets/shoplistbox.cpp
@@ -91,7 +91,7 @@ void ShopListBox::setPlayersMoney(const int money)
 void ShopListBox::draw(Graphics *const graphics)
 {
     BLOCK_START("ShopListBox::draw")
-    if (!mListModel || !mShopItems)
+    if ((mListModel == nullptr) || (mShopItems == nullptr))
     {
         BLOCK_END("ShopListBox::draw")
         return;
@@ -116,7 +116,7 @@ void ShopListBox::draw(Graphics *const graphics)
         Color* backgroundColor = &mBackgroundColor;
 
         ShopItem *const item = mShopItems->at(i);
-        if (item &&
+        if ((item != nullptr) &&
             (item->getDisabled() ||
             (mPlayerMoney < item->getPrice() && mPriceCheck) ||
             (mProtectItems && PlayerInfo::isItemProtected(item->getId()))))
@@ -155,10 +155,10 @@ void ShopListBox::draw(Graphics *const graphics)
                 width, mRowHeight));
         }
 
-        if (mShopItems && item)
+        if ((mShopItems != nullptr) && (item != nullptr))
         {
             Image *const icon = item->getImage();
-            if (icon)
+            if (icon != nullptr)
             {
                 icon->setAlpha(1.0F);
                 graphics->drawImage(icon, mPadding, y + mPadding);
@@ -194,7 +194,7 @@ void ShopListBox::safeDraw(Graphics *const graphics)
 void ShopListBox::adjustSize()
 {
     BLOCK_START("ShopListBox::adjustSize")
-    if (mListModel)
+    if (mListModel != nullptr)
     {
         setHeight(mRowHeight * mListModel->getNumberOfElements()
             + 2 * mPadding);
@@ -209,10 +209,10 @@ void ShopListBox::setPriceCheck(const bool check)
 
 void ShopListBox::mouseMoved(MouseEvent &event)
 {
-    if (!itemPopup || !mRowHeight)
+    if ((itemPopup == nullptr) || (mRowHeight == 0u))
         return;
 
-    if (!mShopItems)
+    if (mShopItems == nullptr)
     {
         itemPopup->hide();
         return;
@@ -227,7 +227,7 @@ void ShopListBox::mouseMoved(MouseEvent &event)
     else
     {
         const Item *const item = mShopItems->at(index);
-        if (item)
+        if (item != nullptr)
         {
             itemPopup->setItem(item, false);
             itemPopup->position(viewport->mMouseX, viewport->mMouseY);
@@ -265,7 +265,7 @@ void ShopListBox::mouseReleased(MouseEvent& event)
             inventory = PlayerInfo::getCartInventory();
         else
             return;
-        if (!inventory)
+        if (inventory == nullptr)
             return;
         Item *const item = inventory->getItem(dragDrop.getTag());
         if (mType == ShopListBoxType::BuyShop)
@@ -292,7 +292,7 @@ void ShopListBox::mouseReleased(MouseEvent& event)
             return;
 
         Item *const item = mShopItems->at(mSelected);
-        if (popupMenu && viewport)
+        if ((popupMenu != nullptr) && (viewport != nullptr))
         {
             popupMenu->showItemPopup(viewport->mMouseX,
             viewport->mMouseY,
@@ -303,7 +303,7 @@ void ShopListBox::mouseReleased(MouseEvent& event)
 
 void ShopListBox::mouseExited(MouseEvent& event A_UNUSED)
 {
-    if (!itemPopup)
+    if (itemPopup == nullptr)
         return;
 
     itemPopup->hide();
diff --git a/src/gui/widgets/shortcutcontainer.cpp b/src/gui/widgets/shortcutcontainer.cpp
index e9611b69f..a2b90514d 100644
--- a/src/gui/widgets/shortcutcontainer.cpp
+++ b/src/gui/widgets/shortcutcontainer.cpp
@@ -61,7 +61,7 @@ ShortcutContainer::ShortcutContainer(Widget2 *const widget) :
     mBackgroundImg = Theme::getImageFromThemeXml(
         "item_shortcut_background.xml", "background.xml");
 
-    if (mBackgroundImg)
+    if (mBackgroundImg != nullptr)
     {
         mBackgroundImg->setAlpha(settings.guiAlpha);
         mBoxHeight = mBackgroundImg->getHeight();
@@ -76,13 +76,13 @@ ShortcutContainer::ShortcutContainer(Widget2 *const widget) :
 
 ShortcutContainer::~ShortcutContainer()
 {
-    if (mBackgroundImg)
+    if (mBackgroundImg != nullptr)
     {
         mBackgroundImg->decRef();
         mBackgroundImg = nullptr;
     }
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     delete2(mVertexes);
@@ -123,7 +123,7 @@ int ShortcutContainer::getIndexFromGrid(const int pointX,
 
 void ShortcutContainer::drawBackground(Graphics *const g)
 {
-    if (mBackgroundImg)
+    if (mBackgroundImg != nullptr)
     {
         if (mRedraw)
         {
@@ -143,7 +143,7 @@ void ShortcutContainer::drawBackground(Graphics *const g)
 
 void ShortcutContainer::safeDrawBackground(Graphics *const g)
 {
-    if (mBackgroundImg)
+    if (mBackgroundImg != nullptr)
     {
         for (unsigned i = 0; i < mMaxItems; i ++)
         {
diff --git a/src/gui/widgets/skilllistbox.h b/src/gui/widgets/skilllistbox.h
index 2bada3a13..93c702381 100644
--- a/src/gui/widgets/skilllistbox.h
+++ b/src/gui/widgets/skilllistbox.h
@@ -58,8 +58,9 @@ class SkillListBox final : public ListBox
             mTextColor(getThemeColor(ThemeColorId::TEXT)),
             mTextColor2(getThemeColor(ThemeColorId::TEXT_OUTLINE)),
             mCooldownColor(getThemeColor(ThemeColorId::SKILL_COOLDOWN)),
-            mTextPadding(mSkin ? mSkin->getOption("textPadding", 34) : 34),
-            mSpacing(mSkin ? mSkin->getOption("spacing", 0) : 0),
+            mTextPadding(mSkin != nullptr ?
+                mSkin->getOption("textPadding", 34) : 34),
+            mSpacing(mSkin != nullptr ? mSkin->getOption("spacing", 0) : 0),
             mSkillClicked(false)
         {
             mRowHeight = getFont()->getHeight() * 2 + mSpacing + 2 * mPadding;
@@ -79,7 +80,7 @@ class SkillListBox final : public ListBox
         SkillInfo *getSelectedInfo() const
         {
             const int selected = getSelected();
-            if (!mListModel || selected < 0
+            if ((mListModel == nullptr) || selected < 0
                 || selected > mListModel->getNumberOfElements())
             {
                 return nullptr;
@@ -90,7 +91,7 @@ class SkillListBox final : public ListBox
 
         void draw(Graphics *const graphics) override final A_NONNULL(2)
         {
-            if (!mListModel)
+            if (mListModel == nullptr)
                 return;
 
             SkillModel *const model = static_cast<SkillModel*>(mListModel);
@@ -121,9 +122,9 @@ class SkillListBox final : public ListBox
                  ++i, y += getRowHeight())
             {
                 SkillInfo *const e = model->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
-                    if (e->cooldown)
+                    if (e->cooldown != 0)
                     {
                         graphics->fillRectangle(Rect(mPadding, y,
                             usableWidth * 100 / e->cooldown, 10));
@@ -136,7 +137,7 @@ class SkillListBox final : public ListBox
                  ++i, y += getRowHeight())
             {
                 SkillInfo *const e = model->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
                     const SkillData *const data = e->data;
                     const std::string &description = data->description;
@@ -183,10 +184,10 @@ class SkillListBox final : public ListBox
         const SkillInfo *getSkillByEvent(const MouseEvent &event) const
         {
             const int y = (event.getY() + mPadding) / getRowHeight();
-            if (!mModel || y >= mModel->getNumberOfElements())
+            if (mModel == nullptr || y >= mModel->getNumberOfElements())
                 return nullptr;
             const SkillInfo *const skill = mModel->getSkillAt(y);
-            if (!skill)
+            if (skill == nullptr)
                 return nullptr;
             return skill;
         }
@@ -194,11 +195,11 @@ class SkillListBox final : public ListBox
         void mouseMoved(MouseEvent &event) override final
         {
             ListBox::mouseMoved(event);
-            if (!viewport || !dragDrop.isEmpty())
+            if ((viewport == nullptr) || !dragDrop.isEmpty())
                 return;
 
             const SkillInfo *const skill = getSkillByEvent(event);
-            if (!skill)
+            if (skill == nullptr)
                 return;
             skillPopup->show(skill,
                 skill->customSelectedLevel,
@@ -219,7 +220,7 @@ class SkillListBox final : public ListBox
                     {
                         mSkillClicked = false;
                         const SkillInfo *const skill = getSkillByEvent(event);
-                        if (!skill)
+                        if (skill == nullptr)
                             return;
                         dragDrop.dragSkill(skill, DragDropSource::Skills);
                         dragDrop.setItem(skill->id + SKILL_MIN_ID);
@@ -245,13 +246,13 @@ class SkillListBox final : public ListBox
                 button == MouseButton::RIGHT)
             {
                 const SkillInfo *const skill = getSkillByEvent(event);
-                if (!skill)
+                if (skill == nullptr)
                     return;
                 event.consume();
                 mSkillClicked = true;
                 SkillModel *const model = static_cast<SkillModel*>(
                     mListModel);
-                if (model &&
+                if ((model != nullptr) &&
                     mSelected >= 0 &&
                     model->getSkillAt(mSelected) == skill)
                 {
diff --git a/src/gui/widgets/skillrectanglelistbox.h b/src/gui/widgets/skillrectanglelistbox.h
index dc5c664d8..88698de1c 100644
--- a/src/gui/widgets/skillrectanglelistbox.h
+++ b/src/gui/widgets/skillrectanglelistbox.h
@@ -73,13 +73,13 @@ class SkillRectangleListBox final : public Widget,
             mTextYOffset(44),
             mSkillClicked(false)
         {
-            if (theme)
+            if (theme != nullptr)
             {
                 mSkin = theme->load("skillrectanglelistbox.xml",
                     "listbox.xml");
             }
 
-            if (mSkin)
+            if (mSkin != nullptr)
             {
                 mPadding = mSkin->getPadding();
                 mBoxWidth = mSkin->getOption("boxWidth", 80);
@@ -103,7 +103,7 @@ class SkillRectangleListBox final : public Widget,
                  ++i)
             {
                 SkillInfo *const e = model->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
                     if (e->x > maxX)
                         maxX = e->x;
@@ -127,7 +127,7 @@ class SkillRectangleListBox final : public Widget,
 
         SkillInfo *getSelectedInfo() const
         {
-            if (!mModel)
+            if (mModel == nullptr)
                 return nullptr;
             const int selected = mSelected;
             if (selected < 0 ||
@@ -141,7 +141,7 @@ class SkillRectangleListBox final : public Widget,
 
         void draw(Graphics *const graphics) override final A_NONNULL(2)
         {
-            if (!mModel)
+            if (mModel == nullptr)
                 return;
 
             SkillModel *const model = mModel;
@@ -155,7 +155,7 @@ class SkillRectangleListBox final : public Widget,
             if (mSelected >= 0)
             {
                 SkillInfo *const e = model->getSkillAt(mSelected);
-                if (e)
+                if (e != nullptr)
                 {
                     const int x = e->x * mBoxWidth + mPadding;
                     const int y = e->y * mBoxHeight + mPadding;
@@ -180,7 +180,7 @@ class SkillRectangleListBox final : public Widget,
                  ++i)
             {
                 SkillInfo *const e = model->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
                     if (e->x > maxX)
                         maxX = e->x;
@@ -235,7 +235,7 @@ class SkillRectangleListBox final : public Widget,
 
         const SkillInfo *getSkillByEvent(const MouseEvent &event) const
         {
-            if (!mModel)
+            if (mModel == nullptr)
                 return nullptr;
             const int posX = (event.getX() - mPadding) / mBoxWidth;
             const int posY = (event.getY() - mPadding) / mBoxHeight;
@@ -244,7 +244,7 @@ class SkillRectangleListBox final : public Widget,
                  ++i)
             {
                 SkillInfo *const e = mModel->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
                     if (posX == e->x && posY == e->y)
                         return e;
@@ -255,7 +255,7 @@ class SkillRectangleListBox final : public Widget,
 
         int getSelectionByEvent(const MouseEvent &event) const
         {
-            if (!mModel)
+            if (mModel == nullptr)
                 return -1;
             const int posX = (event.getX() - mPadding) / mBoxWidth;
             const int posY = (event.getY() - mPadding) / mBoxHeight;
@@ -264,7 +264,7 @@ class SkillRectangleListBox final : public Widget,
                  ++i)
             {
                 SkillInfo *const e = mModel->getSkillAt(i);
-                if (e)
+                if (e != nullptr)
                 {
                     if (posX == e->x && posY == e->y)
                         return i;
@@ -275,11 +275,11 @@ class SkillRectangleListBox final : public Widget,
 
         void mouseMoved(MouseEvent &event) override final
         {
-            if (!viewport || !dragDrop.isEmpty())
+            if ((viewport == nullptr) || !dragDrop.isEmpty())
                 return;
 
             const SkillInfo *const skill = getSkillByEvent(event);
-            if (!skill)
+            if (skill == nullptr)
                 return;
             skillPopup->show(skill,
                 skill->customSelectedLevel,
@@ -302,7 +302,7 @@ class SkillRectangleListBox final : public Widget,
                 {
                     mSkillClicked = false;
                     const SkillInfo *const skill = getSkillByEvent(event);
-                    if (!skill)
+                    if (skill == nullptr)
                         return;
                     dragDrop.dragSkill(skill, DragDropSource::Skills);
                     dragDrop.setItem(skill->id + SKILL_MIN_ID);
@@ -321,12 +321,12 @@ class SkillRectangleListBox final : public Widget,
                 button == MouseButton::RIGHT)
             {
                 const SkillInfo *const skill = getSkillByEvent(event);
-                if (!skill)
+                if (skill == nullptr)
                     return;
                 event.consume();
                 mSkillClicked = true;
                 SkillModel *const model = mModel;
-                if (model &&
+                if ((model != nullptr) &&
                     mSelected >= 0 &&
                     model->getSkillAt(mSelected) == skill)
                 {
@@ -381,7 +381,7 @@ class SkillRectangleListBox final : public Widget,
 
         void setSelected(const int selected)
         {
-            if (!mModel)
+            if (mModel == nullptr)
             {
                 mSelected = -1;
             }
diff --git a/src/gui/widgets/slider.cpp b/src/gui/widgets/slider.cpp
index 2c5ac7c20..0d25ad2c5 100644
--- a/src/gui/widgets/slider.cpp
+++ b/src/gui/widgets/slider.cpp
@@ -132,7 +132,7 @@ Slider::Slider(Widget2 *const widget,
 
 Slider::~Slider()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     delete2(mVertexes);
@@ -158,7 +158,7 @@ void Slider::init()
     // Load resources
     if (mInstances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             for (int mode = 0; mode < 2; mode ++)
                 theme->loadRect(buttons[mode], data[mode], "slider.xml", 0, 8);
@@ -168,7 +168,7 @@ void Slider::init()
 
     mInstances++;
 
-    if (buttons[0].grid[SliderGrid::HGRIP])
+    if (buttons[0].grid[SliderGrid::HGRIP] != nullptr)
         setMarkerLength(buttons[0].grid[SliderGrid::HGRIP]->getWidth());
 }
 
@@ -184,7 +184,7 @@ void Slider::updateAlpha()
         {
             for (int d = 0; d < SliderGrid::SLIDER_MAX; d ++)
             {
-                if (buttons[f].grid[d])
+                if (buttons[f].grid[d] != nullptr)
                     buttons[f].grid[d]->setAlpha(mAlpha);
             }
         }
@@ -194,9 +194,9 @@ void Slider::updateAlpha()
 void Slider::draw(Graphics *const graphics)
 {
     BLOCK_START("Slider::draw")
-    if (!buttons[0].grid[SliderGrid::HSTART] ||
-        !buttons[1].grid[SliderGrid::HSTART] ||
-        !buttons[0].grid[SliderGrid::HEND])
+    if ((buttons[0].grid[SliderGrid::HSTART] == nullptr) ||
+        (buttons[1].grid[SliderGrid::HSTART] == nullptr) ||
+        (buttons[0].grid[SliderGrid::HEND] == nullptr))
     {
         BLOCK_END("Slider::draw")
         return;
@@ -225,7 +225,7 @@ void Slider::draw(Graphics *const graphics)
             w -= width + buttons[0].grid[SliderGrid::HEND]->getWidth();
             x += width;
 
-            if (buttons[0].grid[SliderGrid::HMID])
+            if (buttons[0].grid[SliderGrid::HMID] != nullptr)
             {
                 const Image *const hMid = buttons[0].grid[SliderGrid::HMID];
                 graphics->calcPattern(mVertexes,
@@ -240,7 +240,7 @@ void Slider::draw(Graphics *const graphics)
                 x, y);
 
             const Image *const img = buttons[0].grid[SliderGrid::HGRIP];
-            if (img)
+            if (img != nullptr)
             {
                 graphics->calcTileCollection(mVertexes,
                     img,
@@ -256,11 +256,11 @@ void Slider::draw(Graphics *const graphics)
 
             const int width = buttons[1].grid[SliderGrid::HSTART]->getWidth();
             w -= width;
-            if (buttons[1].grid[SliderGrid::HEND])
+            if (buttons[1].grid[SliderGrid::HEND] != nullptr)
                 w -= buttons[1].grid[SliderGrid::HEND]->getWidth();
             x += width;
 
-            if (buttons[1].grid[SliderGrid::HMID])
+            if (buttons[1].grid[SliderGrid::HMID] != nullptr)
             {
                 const Image *const hMid = buttons[1].grid[SliderGrid::HMID];
                 graphics->calcPattern(mVertexes,
@@ -270,14 +270,14 @@ void Slider::draw(Graphics *const graphics)
             }
 
             x += w;
-            if (buttons[1].grid[SliderGrid::HEND])
+            if (buttons[1].grid[SliderGrid::HEND] != nullptr)
             {
                 graphics->calcTileCollection(mVertexes,
                     buttons[1].grid[SliderGrid::HEND], x, y);
             }
 
             const Image *const img = buttons[1].grid[SliderGrid::HGRIP];
-            if (img)
+            if (img != nullptr)
             {
                 graphics->calcTileCollection(mVertexes,
                     img,
@@ -295,9 +295,9 @@ void Slider::draw(Graphics *const graphics)
 void Slider::safeDraw(Graphics *const graphics)
 {
     BLOCK_START("Slider::draw")
-    if (!buttons[0].grid[SliderGrid::HSTART] ||
-        !buttons[1].grid[SliderGrid::HSTART] ||
-        !buttons[0].grid[SliderGrid::HEND])
+    if ((buttons[0].grid[SliderGrid::HSTART] == nullptr) ||
+        (buttons[1].grid[SliderGrid::HSTART] == nullptr) ||
+        (buttons[0].grid[SliderGrid::HEND] == nullptr))
     {
         BLOCK_END("Slider::draw")
         return;
@@ -319,7 +319,7 @@ void Slider::safeDraw(Graphics *const graphics)
         w -= width + buttons[0].grid[SliderGrid::HEND]->getWidth();
         x += width;
 
-        if (buttons[0].grid[SliderGrid::HMID])
+        if (buttons[0].grid[SliderGrid::HMID] != nullptr)
         {
             const Image *const hMid = buttons[0].grid[SliderGrid::HMID];
             graphics->drawPattern(hMid, x, y, w, hMid->getHeight());
@@ -329,7 +329,7 @@ void Slider::safeDraw(Graphics *const graphics)
         graphics->drawImage(buttons[0].grid[SliderGrid::HEND], x, y);
 
         const Image *const img = buttons[0].grid[SliderGrid::HGRIP];
-        if (img)
+        if (img != nullptr)
         {
             graphics->drawImage(img, getMarkerPosition(),
                 (mDimension.height - img->getHeight()) / 2);
@@ -341,22 +341,22 @@ void Slider::safeDraw(Graphics *const graphics)
 
         const int width = buttons[1].grid[SliderGrid::HSTART]->getWidth();
         w -= width;
-        if (buttons[1].grid[SliderGrid::HEND])
+        if (buttons[1].grid[SliderGrid::HEND] != nullptr)
             w -= buttons[1].grid[SliderGrid::HEND]->getWidth();
         x += width;
 
-        if (buttons[1].grid[SliderGrid::HMID])
+        if (buttons[1].grid[SliderGrid::HMID] != nullptr)
         {
             const Image *const hMid = buttons[1].grid[SliderGrid::HMID];
             graphics->drawPattern(hMid, x, y, w, hMid->getHeight());
         }
 
         x += w;
-        if (buttons[1].grid[SliderGrid::HEND])
+        if (buttons[1].grid[SliderGrid::HEND] != nullptr)
             graphics->drawImage(buttons[1].grid[SliderGrid::HEND], x, y);
 
         const Image *const img = buttons[1].grid[SliderGrid::HGRIP];
-        if (img)
+        if (img != nullptr)
         {
             graphics->drawImage(img, getMarkerPosition(),
                 (mDimension.height - img->getHeight()) / 2);
diff --git a/src/gui/widgets/sliderlist.cpp b/src/gui/widgets/sliderlist.cpp
index 3b42b43e5..edce0cf02 100644
--- a/src/gui/widgets/sliderlist.cpp
+++ b/src/gui/widgets/sliderlist.cpp
@@ -68,7 +68,7 @@ void SliderList::postInit2(ActionListener *const listener,
     if (!eventId.empty())
         setActionEventId(eventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 
     updateLabel();
@@ -135,7 +135,7 @@ void SliderList::safeDraw(Graphics *const graphics)
 
 void SliderList::updateLabel()
 {
-    if (!mListModel || mSelectedIndex < 0
+    if ((mListModel == nullptr) || mSelectedIndex < 0
         || mSelectedIndex >= mListModel->getNumberOfElements())
     {
         return;
@@ -157,7 +157,7 @@ void SliderList::updateLabel()
 
 void SliderList::action(const ActionEvent &event)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return;
 
     const std::string &eventId = event.getId();
@@ -179,7 +179,7 @@ void SliderList::action(const ActionEvent &event)
 
 void SliderList::setSelectedString(const std::string &str)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return;
 
     for (int f = 0; f < mListModel->getNumberOfElements(); f ++)
@@ -194,7 +194,7 @@ void SliderList::setSelectedString(const std::string &str)
 
 std::string SliderList::getSelectedString() const
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return std::string();
 
     return mListModel->getElementAt(mSelectedIndex);
@@ -202,7 +202,7 @@ std::string SliderList::getSelectedString() const
 
 void SliderList::setSelected(const int idx)
 {
-    if (!mListModel)
+    if (mListModel == nullptr)
         return;
 
     mSelectedIndex = idx;
@@ -222,7 +222,7 @@ void SliderList::adjustSize()
 
 int SliderList::getMaxLabelWidth() const
 {
-    if (!mListModel || !gui)
+    if ((mListModel == nullptr) || (gui == nullptr))
         return 1;
 
     int maxWidth = 0;
diff --git a/src/gui/widgets/spellshortcutcontainer.cpp b/src/gui/widgets/spellshortcutcontainer.cpp
index 2b365c52d..6cc4def09 100644
--- a/src/gui/widgets/spellshortcutcontainer.cpp
+++ b/src/gui/widgets/spellshortcutcontainer.cpp
@@ -46,7 +46,7 @@ SpellShortcutContainer::SpellShortcutContainer(Widget2 *const widget,
     mNumber(number),
     mSpellClicked(false)
 {
-    if (spellShortcut)
+    if (spellShortcut != nullptr)
         mMaxItems = spellShortcut->getSpellsCount();
     else
         mMaxItems = 0;
@@ -65,14 +65,14 @@ void SpellShortcutContainer::setWidget2(const Widget2 *const widget)
 
 void SpellShortcutContainer::draw(Graphics *const graphics)
 {
-    if (!spellShortcut)
+    if (spellShortcut == nullptr)
         return;
 
     BLOCK_START("SpellShortcutContainer::draw")
     if (settings.guiAlpha != mAlpha)
     {
         mAlpha = settings.guiAlpha;
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
     }
 
@@ -95,17 +95,17 @@ void SpellShortcutContainer::draw(Graphics *const graphics)
                 mBoxWidth - 1, mBoxHeight - 1));
         }
 
-        if (!spellManager)
+        if (spellManager == nullptr)
             continue;
 
         const TextCommand *const spell = spellManager->getSpell(itemId);
-        if (spell)
+        if (spell != nullptr)
         {
             if (!spell->isEmpty())
             {
                 Image *const image = spell->getImage();
 
-                if (image)
+                if (image != nullptr)
                 {
                     image->setAlpha(1.0F);
                     graphics->drawImage(image, itemX, itemY);
@@ -125,14 +125,14 @@ void SpellShortcutContainer::draw(Graphics *const graphics)
 
 void SpellShortcutContainer::safeDraw(Graphics *const graphics)
 {
-    if (!spellShortcut)
+    if (spellShortcut == nullptr)
         return;
 
     BLOCK_START("SpellShortcutContainer::draw")
     if (settings.guiAlpha != mAlpha)
     {
         mAlpha = settings.guiAlpha;
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
     }
 
@@ -155,17 +155,17 @@ void SpellShortcutContainer::safeDraw(Graphics *const graphics)
                 mBoxWidth - 1, mBoxHeight - 1));
         }
 
-        if (!spellManager)
+        if (spellManager == nullptr)
             continue;
 
         const TextCommand *const spell = spellManager->getSpell(itemId);
-        if (spell)
+        if (spell != nullptr)
         {
             if (!spell->isEmpty())
             {
                 Image *const image = spell->getImage();
 
-                if (image)
+                if (image != nullptr)
                 {
                     image->setAlpha(1.0F);
                     graphics->drawImage(image, itemX, itemY);
@@ -200,7 +200,7 @@ void SpellShortcutContainer::mouseDragged(MouseEvent &event)
                 return;
             event.consume();
             TextCommand *const spell = spellManager->getSpell(itemId);
-            if (spell)
+            if (spell != nullptr)
             {
                 dragDrop.dragCommand(spell, DragDropSource::Spells, index);
                 dragDrop.setItem(spell->getId() + SPELL_MIN_ID);
@@ -234,7 +234,7 @@ void SpellShortcutContainer::mousePressed(MouseEvent &event)
     }
     else if (eventButton == MouseButton::MIDDLE)
     {
-        if (!spellShortcut || !spellManager)
+        if ((spellShortcut == nullptr) || (spellManager == nullptr))
             return;
 
         event.consume();
@@ -245,7 +245,7 @@ void SpellShortcutContainer::mousePressed(MouseEvent &event)
 
 void SpellShortcutContainer::mouseReleased(MouseEvent &event)
 {
-    if (!spellShortcut || !spellManager)
+    if ((spellShortcut == nullptr) || (spellManager == nullptr))
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -287,11 +287,11 @@ void SpellShortcutContainer::mouseReleased(MouseEvent &event)
             {
                 const TextCommand *const
                     spell = spellManager->getSpell(itemId);
-                if (spell && !spell->isEmpty())
+                if ((spell != nullptr) && !spell->isEmpty())
                 {
                     const int num = itemShortcutWindow->getTabIndex();
                     if (num >= 0 && num < CAST_S32(SHORTCUT_TABS)
-                        && itemShortcut[num])
+                        && (itemShortcut[num] != nullptr))
                     {
                         itemShortcut[num]->setItemSelected(
                             spell->getId() + SPELL_MIN_ID);
@@ -303,7 +303,7 @@ void SpellShortcutContainer::mouseReleased(MouseEvent &event)
             {
                 const int num = itemShortcutWindow->getTabIndex();
                 if (num >= 0 && num < CAST_S32(SHORTCUT_TABS)
-                    && itemShortcut[num])
+                    && (itemShortcut[num] != nullptr))
                 {
                     itemShortcut[num]->setItemSelected(-1);
                 }
@@ -317,7 +317,7 @@ void SpellShortcutContainer::mouseReleased(MouseEvent &event)
         if (itemId >= 0)
             spell = spellManager->getSpell(itemId);
 
-        if (spell && popupMenu)
+        if ((spell != nullptr) && (popupMenu != nullptr))
         {
             popupMenu->showSpellPopup(viewport->mMouseX,
                 viewport->mMouseY,
@@ -329,8 +329,12 @@ void SpellShortcutContainer::mouseReleased(MouseEvent &event)
 // Show ItemTooltip
 void SpellShortcutContainer::mouseMoved(MouseEvent &event)
 {
-    if (!spellPopup || !spellShortcut || !spellManager)
+    if (spellPopup == nullptr ||
+        spellShortcut == nullptr ||
+        spellManager == nullptr)
+    {
         return;
+    }
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
 
@@ -340,7 +344,7 @@ void SpellShortcutContainer::mouseMoved(MouseEvent &event)
     const int itemId = getItemByIndex(index);
     spellPopup->setVisible(Visible_false);
     const TextCommand *const spell = spellManager->getSpell(itemId);
-    if (spell && !spell->isEmpty())
+    if ((spell != nullptr) && !spell->isEmpty())
     {
         spellPopup->setItem(spell);
         spellPopup->view(viewport->mMouseX, viewport->mMouseY);
@@ -353,13 +357,13 @@ void SpellShortcutContainer::mouseMoved(MouseEvent &event)
 
 void SpellShortcutContainer::mouseExited(MouseEvent &event A_UNUSED)
 {
-    if (spellPopup)
+    if (spellPopup != nullptr)
         spellPopup->setVisible(Visible_false);
 }
 
 void SpellShortcutContainer::widgetHidden(const Event &event A_UNUSED)
 {
-    if (spellPopup)
+    if (spellPopup != nullptr)
         spellPopup->setVisible(Visible_false);
 }
 
diff --git a/src/gui/widgets/statspage.cpp b/src/gui/widgets/statspage.cpp
index db46931eb..eca98b1c4 100644
--- a/src/gui/widgets/statspage.cpp
+++ b/src/gui/widgets/statspage.cpp
@@ -72,7 +72,7 @@ void StatsPage::attributeChanged(const AttributesT id,
                                  const int newVal A_UNUSED)
 {
     const Attrs::const_iterator it = mAttrs.find(id);
-    if (it != mAttrs.end() && it->second)
+    if (it != mAttrs.end() && (it->second != nullptr))
         it->second->update();
 }
 
@@ -81,6 +81,6 @@ void StatsPage::statChanged(const AttributesT id,
                             const int oldVal2 A_UNUSED)
 {
     const Attrs::const_iterator it = mAttrs.find(id);
-    if (it != mAttrs.end() && it->second)
+    if (it != mAttrs.end() && (it->second != nullptr))
         it->second->update();
 }
diff --git a/src/gui/widgets/statspagebasic.cpp b/src/gui/widgets/statspagebasic.cpp
index 23fd22243..bdf90e14f 100644
--- a/src/gui/widgets/statspagebasic.cpp
+++ b/src/gui/widgets/statspagebasic.cpp
@@ -83,7 +83,7 @@ void StatsPageBasic::statChanged(const AttributesT id,
                                  const int oldVal2 A_UNUSED)
 {
     const Attrs::const_iterator it = mAttrs.find(id);
-    if (it != mAttrs.end() && it->second)
+    if (it != mAttrs.end() && (it->second != nullptr))
         it->second->update();
 }
 
@@ -105,7 +105,7 @@ void StatsPageBasic::attributeChanged(const AttributesT id,
             for (Attrs::const_iterator it = mAttrs.begin();
                  it != mAttrs.end(); ++it)
             {
-                if (it->second)
+                if (it->second != nullptr)
                     it->second->update();
             }
             return;
@@ -115,7 +115,7 @@ void StatsPageBasic::attributeChanged(const AttributesT id,
             for (Attrs::const_iterator it = mAttrs.begin();
                  it != mAttrs.end(); ++it)
             {
-                if (it->second)
+                if (it->second != nullptr)
                     it->second->update();
             }
             return;
@@ -125,7 +125,7 @@ void StatsPageBasic::attributeChanged(const AttributesT id,
     }
     PRAGMA45(GCC diagnostic pop)
     const Attrs::const_iterator it = mAttrs.find(id);
-    if (it != mAttrs.end() && it->second)
+    if (it != mAttrs.end() && (it->second != nullptr))
         it->second->update();
 }
 
@@ -137,7 +137,7 @@ void StatsPageBasic::setPointsNeeded(const AttributesT id,
     if (it != mAttrs.end())
     {
         AttrDisplay *const disp = it->second;
-        if (disp && disp->getType() == AttrDisplay::CHANGEABLE)
+        if ((disp != nullptr) && disp->getType() == AttrDisplay::CHANGEABLE)
             static_cast<ChangeDisplay*>(disp)->setPointsNeeded(needed);
     }
 }
@@ -151,7 +151,7 @@ std::string StatsPageBasic::getStatsStr() const
     {
         const ChangeDisplay *const attr = dynamic_cast<ChangeDisplay*>(
             (*it).second);
-        if (attr)
+        if (attr != nullptr)
         {
             str.append(strprintf("%s:%s ", attr->getShortName().c_str(),
                 attr->getValue().c_str()));
diff --git a/src/gui/widgets/tabbedarea.cpp b/src/gui/widgets/tabbedarea.cpp
index 6df39dfe6..95ea305d6 100644
--- a/src/gui/widgets/tabbedarea.cpp
+++ b/src/gui/widgets/tabbedarea.cpp
@@ -120,7 +120,7 @@ void TabbedArea::postInit()
 
 TabbedArea::~TabbedArea()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     // +++ virtual method calls
@@ -141,16 +141,16 @@ void TabbedArea::enableScrollButtons(const bool enable)
 {
     if (mEnableScrollButtons && !enable)
     {
-        if (mArrowButton[0])
+        if (mArrowButton[0] != nullptr)
             remove(mArrowButton[0]);
-        if (mArrowButton[1])
+        if (mArrowButton[1] != nullptr)
             remove(mArrowButton[1]);
     }
     else if (!mEnableScrollButtons && enable)
     {
-        if (mArrowButton[0])
+        if (mArrowButton[0] != nullptr)
             add(mArrowButton[0]);
-        if (mArrowButton[1])
+        if (mArrowButton[1] != nullptr)
             add(mArrowButton[1]);
     }
     mEnableScrollButtons = enable;
@@ -220,7 +220,7 @@ Widget *TabbedArea::getCurrentWidget() const
 {
     const Tab *const tab = getSelectedTab();
 
-    if (tab)
+    if (tab != nullptr)
         return getWidget(tab->getCaption());
     else
         return nullptr;
@@ -229,7 +229,7 @@ Widget *TabbedArea::getCurrentWidget() const
 void TabbedArea::addTab(Tab *const tab,
                         Widget *const widget)
 {
-    if (!tab || !widget)
+    if ((tab == nullptr) || (widget == nullptr))
         return;
 
     tab->setTabbedArea(this);
@@ -238,7 +238,7 @@ void TabbedArea::addTab(Tab *const tab,
     mTabContainer->add(tab);
     mTabs.push_back(std::pair<Tab*, Widget*>(tab, widget));
 
-    if (!mSelectedTab && tab->mVisible == Visible_true)
+    if ((mSelectedTab == nullptr) && tab->mVisible == Visible_true)
         setSelectedTab(tab);
 
     adjustTabPositions();
@@ -255,7 +255,7 @@ void TabbedArea::addTab(Tab *const tab,
 
 void TabbedArea::adjustWidget(Widget *const widget) const
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     const int frameSize = 2 * mFrameSize;
     widget->setSize(getWidth() - frameSize,
@@ -386,7 +386,7 @@ void TabbedArea::mousePressed(MouseEvent &event)
             event.getX(), event.getY());
         Tab *const tab = dynamic_cast<Tab *>(widget);
 
-        if (tab)
+        if (tab != nullptr)
         {
             event.consume();
             setSelectedTab(tab);
@@ -414,7 +414,7 @@ void TabbedArea::setSelectedTab(Tab *const tab)
 
     Tab *const newTab = tab;
 
-    if (newTab)
+    if (newTab != nullptr)
         newTab->setCurrent();
 
     widgetResized(Event(nullptr));
@@ -428,7 +428,7 @@ void TabbedArea::setSelectedTabDefault()
         for (size_t i = 0; i < mTabs.size(); i++)
         {
             Tab *const tab = mTabs[i].first;
-            if (tab && tab->mVisible == Visible_true)
+            if ((tab != nullptr) && tab->mVisible == Visible_true)
             {
                 setSelectedTab(tab);
                 return;
@@ -454,7 +454,7 @@ void TabbedArea::setSelectedTabByName(const std::string &name)
 {
     FOR_EACH (TabContainer::const_iterator, itr, mTabs)
     {
-        if ((*itr).first && (*itr).first->getCaption() == name)
+        if (((*itr).first != nullptr) && (*itr).first->getCaption() == name)
         {
             setSelectedTab((*itr).first);
             return;
@@ -476,7 +476,7 @@ void TabbedArea::widgetResized(const Event &event A_UNUSED)
 
     Widget *const w = getCurrentWidget();
     ScrollArea *const scr = dynamic_cast<ScrollArea *>(w);
-    if (scr)
+    if (scr != nullptr)
     {
         if (mFollowDownScroll && height != 0)
         {
@@ -492,14 +492,14 @@ void TabbedArea::widgetResized(const Event &event A_UNUSED)
                         + rect.height - height;
                     w->setSize(mWidgetContainer->getWidth() - frameSize,
                         mWidgetContainer->getHeight() - frameSize);
-                    if (newScroll)
+                    if (newScroll != 0)
                         scr->setVerticalScrollAmount(newScroll);
                 }
             }
         }
     }
 
-    if (mArrowButton[1])
+    if (mArrowButton[1] != nullptr)
     {
         // Check whether there is room to show more tabs now.
         int innerWidth = w1 - 4 - mArrowButton[0]->getWidth()
@@ -508,10 +508,10 @@ void TabbedArea::widgetResized(const Event &event A_UNUSED)
             innerWidth = 0;
 
         int newWidth = mVisibleTabsWidth;
-        while (mTabScrollIndex && newWidth < innerWidth)
+        while ((mTabScrollIndex != 0u) && newWidth < innerWidth)
         {
             Tab *const tab = mTabs[mTabScrollIndex - 1].first;
-            if (tab && tab->mVisible == Visible_true)
+            if ((tab != nullptr) && tab->mVisible == Visible_true)
             {
                 newWidth += tab->getWidth();
                 if (newWidth < innerWidth)
@@ -519,7 +519,7 @@ void TabbedArea::widgetResized(const Event &event A_UNUSED)
             }
         }
 
-        if (mArrowButton[1])
+        if (mArrowButton[1] != nullptr)
         {
             // Move the right arrow to fit the windows content.
             newWidth = width - mArrowButton[1]->getWidth() - mRightMargin;
@@ -539,7 +539,7 @@ void TabbedArea::updateTabsWidth()
     FOR_EACH (TabContainer::const_iterator, itr, mTabs)
     {
         Tab *const tab = (*itr).first;
-        if (tab && tab->mVisible == Visible_true)
+        if ((tab != nullptr) && tab->mVisible == Visible_true)
             mTabsWidth += tab->getWidth();
     }
     updateVisibleTabsWidth();
@@ -551,7 +551,7 @@ void TabbedArea::updateVisibleTabsWidth()
     for (size_t i = mTabScrollIndex, sz = mTabs.size(); i < sz; ++i)
     {
         Tab *const tab = mTabs[i].first;
-        if (tab && tab->mVisible == Visible_true)
+        if ((tab != nullptr) && tab->mVisible == Visible_true)
             mVisibleTabsWidth += CAST_S32(tab->getWidth());
     }
 }
@@ -574,7 +574,7 @@ void TabbedArea::adjustSize()
     mWidgetContainer->setPosition(0, maxTabHeight);
     mWidgetContainer->setSize(width, height - maxTabHeight);
     Widget *const w = getCurrentWidget();
-    if (w)
+    if (w != nullptr)
     {
         const int wFrameSize = w->getFrameSize();
         const int frame2 = 2 * wFrameSize;
@@ -600,7 +600,7 @@ void TabbedArea::adjustTabPositions()
     for (size_t i = 0; i < sz; ++i)
     {
         const Tab *const tab = mTabs[i].first;
-        if (tab &&
+        if ((tab != nullptr) &&
             tab->mVisible == Visible_true &&
             tab->getHeight() > maxTabHeight)
         {
@@ -613,7 +613,7 @@ void TabbedArea::adjustTabPositions()
     for (size_t i = mTabScrollIndex; i < sz; ++i)
     {
         Tab *const tab = mTabs[i].first;
-        if (!tab || tab->mVisible == Visible_false)
+        if ((tab == nullptr) || tab->mVisible == Visible_false)
             continue;
         tab->setPosition(x, maxTabHeight - tab->getHeight());
         x += tab->getWidth();
@@ -626,7 +626,7 @@ void TabbedArea::adjustTabPositions()
         for (unsigned i = 0; i < mTabScrollIndex; ++i)
         {
             Tab *const tab = mTabs[i].first;
-            if (tab && tab->mVisible == Visible_true)
+            if ((tab != nullptr) && tab->mVisible == Visible_true)
             {
                 x -= tab->getWidth();
                 tab->setPosition(x, maxTabHeight - tab->getHeight());
@@ -640,7 +640,7 @@ void TabbedArea::action(const ActionEvent& actionEvent)
     Widget *const source = actionEvent.getSource();
     Tab *const tab = dynamic_cast<Tab *>(source);
 
-    if (tab)
+    if (tab != nullptr)
     {
         setSelectedTab(tab);
     }
@@ -649,7 +649,7 @@ void TabbedArea::action(const ActionEvent& actionEvent)
         const std::string &eventId = actionEvent.getId();
         if (eventId == "shift_left")
         {
-            if (mTabScrollIndex)
+            if (mTabScrollIndex != 0u)
                 --mTabScrollIndex;
         }
         else if (eventId == "shift_right")
@@ -665,7 +665,7 @@ void TabbedArea::action(const ActionEvent& actionEvent)
 void TabbedArea::updateArrowEnableState()
 {
     updateTabsWidth();
-    if (!mArrowButton[0] || !mArrowButton[1])
+    if ((mArrowButton[0] == nullptr) || (mArrowButton[1] == nullptr))
         return;
 
     const int width = mDimension.width;
@@ -684,7 +684,7 @@ void TabbedArea::updateArrowEnableState()
     }
 
     // Left arrow consistency check
-    if (!mTabScrollIndex)
+    if (mTabScrollIndex == 0u)
         mArrowButton[0]->setEnabled(false);
     else
         mArrowButton[0]->setEnabled(true);
@@ -801,7 +801,7 @@ void TabbedArea::death(const Event &event)
 {
     Tab *const tab = dynamic_cast<Tab*>(event.getSource());
 
-    if (tab)
+    if (tab != nullptr)
         removeTab(tab);
     else
         BasicContainer::death(event);
diff --git a/src/gui/widgets/tabs/chat/channeltab.cpp b/src/gui/widgets/tabs/chat/channeltab.cpp
index d67de5287..37e6237a0 100644
--- a/src/gui/widgets/tabs/chat/channeltab.cpp
+++ b/src/gui/widgets/tabs/chat/channeltab.cpp
@@ -39,7 +39,7 @@ ChannelTab::ChannelTab(const Widget2 *const widget,
 
 ChannelTab::~ChannelTab()
 {
-    if (chatWindow)
+    if (chatWindow != nullptr)
         chatWindow->removeChannel(mChannelName);
 }
 
@@ -55,11 +55,11 @@ bool ChannelTab::handleCommand(const std::string &restrict type,
 {
     if (type == "close")
     {
-        if (windowContainer)
+        if (windowContainer != nullptr)
             windowContainer->scheduleDelete(this);
         else
             delete this;
-        if (chatWindow)
+        if (chatWindow != nullptr)
             chatWindow->defaultTab();
     }
     else
diff --git a/src/gui/widgets/tabs/chat/chattab.cpp b/src/gui/widgets/tabs/chat/chattab.cpp
index e59d11eb4..fc2f09350 100644
--- a/src/gui/widgets/tabs/chat/chattab.cpp
+++ b/src/gui/widgets/tabs/chat/chattab.cpp
@@ -84,7 +84,7 @@ ChatTab::ChatTab(const Widget2 *const widget,
 
     mTextOutput->setOpaque(Opaque_false);
     mTextOutput->setMaxRow(config.getIntValue("ChatLogLength"));
-    if (chatWindow)
+    if (chatWindow != nullptr)
         mTextOutput->setLinkHandler(chatWindow->mItemLinkHandler);
     mTextOutput->setAlwaysUpdate(false);
 
@@ -92,13 +92,13 @@ ChatTab::ChatTab(const Widget2 *const widget,
         ScrollArea::SHOW_ALWAYS);
     mScrollArea->setScrollAmount(0, 1);
 
-    if (chatWindow)
+    if (chatWindow != nullptr)
         chatWindow->addTab(this);
 }
 
 ChatTab::~ChatTab()
 {
-    if (chatWindow)
+    if (chatWindow != nullptr)
         chatWindow->removeTab(this);
 
     delete2(mTextOutput);
@@ -225,7 +225,7 @@ void ChatTab::chatLog(std::string line,
 
     // if configured, move magic messages log to debug chat tab
     if (Net::getNetworkType() == ServerType::TMWATHENA
-        && localChatTab && this == localChatTab
+        && (localChatTab != nullptr) && this == localChatTab
         && ((config.getBoolValue("showMagicInDebug")
         && own == ChatMsgType::BY_PLAYER
         && tmp.text.length() > 1
@@ -235,7 +235,7 @@ void ChatTab::chatLog(std::string line,
         && (own == ChatMsgType::BY_SERVER
         || tmp.nick.empty()))))
     {
-        if (debugChatTab)
+        if (debugChatTab != nullptr)
             debugChatTab->chatLog(line, own, ignoreRecord, tryRemoveColors);
         return;
     }
@@ -247,7 +247,7 @@ void ChatTab::chatLog(std::string line,
     if (config.getBoolValue("useLocalTime"))
     {
         const tm *const timeInfo = localtime(&t);
-        if (timeInfo)
+        if (timeInfo != nullptr)
         {
             line = strprintf("%s[%02d:%02d] %s%s", lineColor.c_str(),
                 timeInfo->tm_hour, timeInfo->tm_min, tmp.nick.c_str(),
@@ -292,7 +292,7 @@ void ChatTab::chatLog(std::string line,
         addRow(line);
     }
 
-    if (chatWindow && this == localChatTab)
+    if ((chatWindow != nullptr) && this == localChatTab)
         chatWindow->addToAwayLog(line);
 
     mScrollArea->logic();
@@ -307,7 +307,7 @@ void ChatTab::chatLog(std::string line,
         }
 
         const TabbedArea *const tabArea = getTabbedArea();
-        if (!tabArea)
+        if (tabArea == nullptr)
             return;
 
         const bool notFocused = WindowManager::getIsMinimized() ||
@@ -317,7 +317,8 @@ void ChatTab::chatLog(std::string line,
         {
             if (getFlash() == 0)
             {
-                if (chatWindow && chatWindow->findHighlight(tmp.text))
+                if (chatWindow != nullptr &&
+                    chatWindow->findHighlight(tmp.text))
                 {
                     setFlash(2);
                     soundManager.playGuiSound(SOUND_HIGHLIGHT);
@@ -329,8 +330,11 @@ void ChatTab::chatLog(std::string line,
             }
             else if (getFlash() == 2)
             {
-                if (chatWindow && chatWindow->findHighlight(tmp.text))
+                if (chatWindow != nullptr &&
+                    chatWindow->findHighlight(tmp.text))
+                {
                     soundManager.playGuiSound(SOUND_HIGHLIGHT);
+                }
             }
         }
 
@@ -341,13 +345,13 @@ void ChatTab::chatLog(std::string line,
         {
             if (own == ChatMsgType::BY_GM)
             {
-                if (chatWindow)
+                if (chatWindow != nullptr)
                     chatWindow->unHideWindow();
                 soundManager.playGuiSound(SOUND_GLOBAL);
             }
             else if (own != ChatMsgType::BY_SERVER)
             {
-                if (chatWindow)
+                if (chatWindow != nullptr)
                     chatWindow->unHideWindow();
                 playNewMessageSound();
             }
@@ -358,7 +362,7 @@ void ChatTab::chatLog(std::string line,
 
 void ChatTab::chatLog(const std::string &nick, std::string msg)
 {
-    if (!localPlayer)
+    if (localPlayer == nullptr)
         return;
 
     const ChatMsgTypeT byWho = (nick == localPlayer->getName()
@@ -441,7 +445,7 @@ void ChatTab::handleCommandStr(const std::string &msg)
 
 void ChatTab::handleHelp(const std::string &msg)
 {
-    if (helpWindow)
+    if (helpWindow != nullptr)
     {
         helpWindow->search(msg);
         helpWindow->requestMoveToTop();
@@ -457,7 +461,7 @@ bool ChatTab::handleCommands(const std::string &type, const std::string &args)
 
 void ChatTab::saveToLogFile(const std::string &msg) const
 {
-    if (chatLogger)
+    if (chatLogger != nullptr)
     {
         if (getType() == ChatTabType::INPUT)
         {
@@ -498,7 +502,7 @@ void ChatTab::addRow(std::string &line)
 
 void ChatTab::loadFromLogFile(const std::string &name)
 {
-    if (chatLogger)
+    if (chatLogger != nullptr)
     {
         std::list<std::string> list;
         chatLogger->loadLast(name, list, 5);
diff --git a/src/gui/widgets/tabs/chat/emulateguildtab.cpp b/src/gui/widgets/tabs/chat/emulateguildtab.cpp
index 4c4401242..4374f6b2c 100644
--- a/src/gui/widgets/tabs/chat/emulateguildtab.cpp
+++ b/src/gui/widgets/tabs/chat/emulateguildtab.cpp
@@ -56,13 +56,15 @@ EmulateGuildTab::~EmulateGuildTab()
 bool EmulateGuildTab::handleCommand(const std::string &restrict type,
                                     const std::string &restrict args)
 {
-    if (type == "invite" && guildManager)
+    if (guildManager == nullptr)
+        return false;
+    if (type == "invite")
         guildManager->invite(args);
-    else if (type == "leave" && guildManager)
+    else if (type == "leave")
         guildManager->leave();
-    else if (type == "kick" && guildManager)
+    else if (type == "kick")
         guildManager->kick(args);
-    else if (type == "notice" && guildManager)
+    else if (type == "notice")
         guildManager->notice(args);
     else
         return false;
@@ -72,14 +74,14 @@ bool EmulateGuildTab::handleCommand(const std::string &restrict type,
 
 void EmulateGuildTab::handleInput(const std::string &msg)
 {
-    if (!guildManager)
+    if (guildManager == nullptr)
         return;
     guildManager->chat(ChatWindow::doReplace(msg));
 }
 
 void EmulateGuildTab::getAutoCompleteList(StringVect &names) const
 {
-    if (!guildManager)
+    if (guildManager == nullptr)
         return;
 
     guildManager->getNames(names);
diff --git a/src/gui/widgets/tabs/chat/guildtab.cpp b/src/gui/widgets/tabs/chat/guildtab.cpp
index 982c27da5..51416b8ef 100644
--- a/src/gui/widgets/tabs/chat/guildtab.cpp
+++ b/src/gui/widgets/tabs/chat/guildtab.cpp
@@ -60,23 +60,23 @@ GuildTab::~GuildTab()
 bool GuildTab::handleCommand(const std::string &restrict type,
                              const std::string &restrict args)
 {
-    if (type == "invite" && EAthena::taGuild)
+    if (type == "invite" && (EAthena::taGuild != nullptr))
     {
         guildHandler->invite(args);
     }
-    else if (type == "leave" && EAthena::taGuild)
+    else if (type == "leave" && (EAthena::taGuild != nullptr))
     {
         inputManager.executeChatCommand(InputAction::LEAVE_GUILD,
             std::string(),
             this);
     }
-    else if (type == "kick" && EAthena::taGuild)
+    else if (type == "kick" && (EAthena::taGuild != nullptr))
     {
         inputManager.executeChatCommand(InputAction::KICK_GUILD,
             args,
             this);
     }
-    else if (type == "notice" && EAthena::taGuild)
+    else if (type == "notice" && (EAthena::taGuild != nullptr))
     {
         inputManager.executeChatCommand(InputAction::GUILD_NOTICE,
             args,
@@ -92,7 +92,7 @@ bool GuildTab::handleCommand(const std::string &restrict type,
 
 void GuildTab::handleInput(const std::string &msg)
 {
-    if (!EAthena::taGuild)
+    if (EAthena::taGuild == nullptr)
         return;
 
     guildHandler->chat(ChatWindow::doReplace(msg));
@@ -100,7 +100,7 @@ void GuildTab::handleInput(const std::string &msg)
 
 void GuildTab::getAutoCompleteList(StringVect &names) const
 {
-    if (EAthena::taGuild)
+    if (EAthena::taGuild != nullptr)
         EAthena::taGuild->getNames(names);
 }
 
diff --git a/src/gui/widgets/tabs/chat/partytab.cpp b/src/gui/widgets/tabs/chat/partytab.cpp
index 366a78241..befbb0393 100644
--- a/src/gui/widgets/tabs/chat/partytab.cpp
+++ b/src/gui/widgets/tabs/chat/partytab.cpp
@@ -118,12 +118,12 @@ bool PartyTab::handleCommand(const std::string &restrict type,
 
 void PartyTab::getAutoCompleteList(StringVect &names) const
 {
-    if (!localPlayer)
+    if (localPlayer == nullptr)
         return;
 
     const Party *const p = localPlayer->getParty();
 
-    if (p)
+    if (p != nullptr)
         p->getNames(names);
 }
 
diff --git a/src/gui/widgets/tabs/chat/whispertab.cpp b/src/gui/widgets/tabs/chat/whispertab.cpp
index 1cbf471c7..d8672b22d 100644
--- a/src/gui/widgets/tabs/chat/whispertab.cpp
+++ b/src/gui/widgets/tabs/chat/whispertab.cpp
@@ -45,7 +45,7 @@ WhisperTab::WhisperTab(const Widget2 *const widget,
 
 WhisperTab::~WhisperTab()
 {
-    if (chatWindow)
+    if (chatWindow != nullptr)
         chatWindow->removeWhisper(mNick);
 }
 
@@ -55,7 +55,7 @@ void WhisperTab::handleInput(const std::string &msg)
     newMsg = ChatWindow::doReplace(msg);
     chatHandler->privateMessage(mNick, newMsg);
 
-    if (localPlayer)
+    if (localPlayer != nullptr)
         chatLog(localPlayer->getName(), newMsg);
     else
         chatLog("?", newMsg);
@@ -78,7 +78,7 @@ void WhisperTab::handleCommandStr(const std::string &msg)
     {
         std::string str = textToMe(args);
         chatHandler->privateMessage(mNick, str);
-        if (localPlayer)
+        if (localPlayer != nullptr)
             chatLog(localPlayer->getName(), str);
         else
             chatLog("?", str);
@@ -94,11 +94,11 @@ bool WhisperTab::handleCommand(const std::string &restrict type,
 {
     if (type == "close")
     {
-        if (windowContainer)
+        if (windowContainer != nullptr)
             windowContainer->scheduleDelete(this);
         else
             delete this;
-        if (chatWindow)
+        if (chatWindow != nullptr)
             chatWindow->defaultTab();
     }
     else
diff --git a/src/gui/widgets/tabs/debugwindowtabs.cpp b/src/gui/widgets/tabs/debugwindowtabs.cpp
index e75e1d42d..4a600d2fd 100644
--- a/src/gui/widgets/tabs/debugwindowtabs.cpp
+++ b/src/gui/widgets/tabs/debugwindowtabs.cpp
@@ -171,7 +171,7 @@ MapDebugTab::MapDebugTab(const Widget2 *const widget) :
 void MapDebugTab::logic()
 {
     BLOCK_START("MapDebugTab::logic")
-    if (localPlayer)
+    if (localPlayer != nullptr)
     {
         // TRANSLATORS: debug window label
         mXYLabel->setCaption(strprintf("%s (%d, %d)", _("Player Position:"),
@@ -184,7 +184,7 @@ void MapDebugTab::logic()
     }
 
     const Map *const map = Game::instance()->getCurrentMap();
-    if (map && viewport)
+    if ((map != nullptr) && (viewport != nullptr))
     {
           // Get the current mouse position
         const int mouseTileX = (viewport->mMouseX + viewport->getCameraX())
@@ -329,7 +329,7 @@ TargetDebugTab::TargetDebugTab(const Widget2 *const widget) :
 void TargetDebugTab::logic()
 {
     BLOCK_START("TargetDebugTab::logic")
-    if (localPlayer && localPlayer->getTarget())
+    if ((localPlayer != nullptr) && (localPlayer->getTarget() != nullptr))
     {
         const Being *const target = localPlayer->getTarget();
 
@@ -344,7 +344,7 @@ void TargetDebugTab::logic()
         mTargetTypeLabel->setCaption(strprintf("%s %d",
             // TRANSLATORS: debug window label
             _("Target type:"), toInt(target->getSubType(), int)));
-        if (target->getLevel())
+        if (target->getLevel() != 0)
         {
             mTargetLevelLabel->setCaption(strprintf("%s %d",
                 // TRANSLATORS: debug window label
@@ -389,7 +389,7 @@ void TargetDebugTab::logic()
             _("Effects:"), target->getStatusEffectsString().c_str()));
 
         const int delay = target->getAttackDelay();
-        if (delay)
+        if (delay != 0)
         {
             mAttackDelayLabel->setCaption(strprintf("%s %d",
                 // TRANSLATORS: debug window label
@@ -469,7 +469,7 @@ NetDebugTab::NetDebugTab(const Widget2 *const widget) :
 void NetDebugTab::logic()
 {
     BLOCK_START("NetDebugTab::logic")
-    if (localPlayer)
+    if (localPlayer != nullptr)
     {
         // TRANSLATORS: debug window label
         mPingLabel->setCaption(strprintf(_("Ping: %s ms"),
diff --git a/src/gui/widgets/tabs/setup_audio.cpp b/src/gui/widgets/tabs/setup_audio.cpp
index 0b958951a..7a37f2d89 100644
--- a/src/gui/widgets/tabs/setup_audio.cpp
+++ b/src/gui/widgets/tabs/setup_audio.cpp
@@ -181,10 +181,10 @@ void Setup_Audio::apply()
         soundManager.init();
         if (config.getBoolValue("playMusic"))
         {
-            if (viewport)
+            if (viewport != nullptr)
             {  // in game
                 const Map *const map = viewport->getMap();
-                if (map)
+                if (map != nullptr)
                 {
                     soundManager.playMusic(map->getMusicFile(),
                         SkipError_false);
diff --git a/src/gui/widgets/tabs/setup_chat.cpp b/src/gui/widgets/tabs/setup_chat.cpp
index c9d0565b9..b27e1ec53 100644
--- a/src/gui/widgets/tabs/setup_chat.cpp
+++ b/src/gui/widgets/tabs/setup_chat.cpp
@@ -333,7 +333,7 @@ void Setup_Chat::apply()
 {
     SetupTabScroll::apply();
 
-    if (chatWindow)
+    if (chatWindow != nullptr)
     {
         chatWindow->adjustTabSize();
         chatWindow->parseHighlights();
diff --git a/src/gui/widgets/tabs/setup_colors.cpp b/src/gui/widgets/tabs/setup_colors.cpp
index 9f7ad0154..f4efb2832 100644
--- a/src/gui/widgets/tabs/setup_colors.cpp
+++ b/src/gui/widgets/tabs/setup_colors.cpp
@@ -201,7 +201,7 @@ Setup_Colors::Setup_Colors(const Widget2 *const widget) :
 
 Setup_Colors::~Setup_Colors()
 {
-    if (mPreviewBox && mPreviewBox->getContent() == mPreview)
+    if ((mPreviewBox != nullptr) && mPreviewBox->getContent() == mPreview)
         delete2(mTextPreview)
     else
         delete2(mPreview)
@@ -246,7 +246,7 @@ void Setup_Colors::action(const ActionEvent &event)
 
 void Setup_Colors::valueChanged(const SelectionEvent &event A_UNUSED)
 {
-    if (!userPalette)
+    if (userPalette == nullptr)
         return;
 
     mSelected = mColorBox->getSelected();
@@ -308,7 +308,7 @@ void Setup_Colors::valueChanged(const SelectionEvent &event A_UNUSED)
             break;
         case UserColorId::ATTACK_RANGE_BORDER:
         case UserColorId::HOME_PLACE_BORDER:
-            if (gui)
+            if (gui != nullptr)
                 mTextPreview->setFont(gui->getFont());
             mTextPreview->setTextColor(col);
             mTextPreview->setOutline(false);
@@ -398,21 +398,21 @@ void Setup_Colors::valueChanged(const SelectionEvent &event A_UNUSED)
 void Setup_Colors::setEntry(Slider *const s, TextField *const t,
                             const int value)
 {
-    if (s)
+    if (s != nullptr)
         s->setValue(value);
-    if (t)
+    if (t != nullptr)
         t->setText(toString(value));
 }
 
 void Setup_Colors::apply()
 {
-    if (userPalette)
+    if (userPalette != nullptr)
         userPalette->commit();
 }
 
 void Setup_Colors::cancel()
 {
-    if (!userPalette)
+    if (userPalette == nullptr)
         return;
 
     userPalette->rollback();
@@ -430,7 +430,7 @@ void Setup_Colors::cancel()
 
 void Setup_Colors::updateGradType()
 {
-    if (mSelected == -1 || !userPalette)
+    if (mSelected == -1 || (userPalette == nullptr))
         return;
 
     mSelected = mColorBox->getSelected();
@@ -463,7 +463,7 @@ void Setup_Colors::updateGradType()
 
 void Setup_Colors::updateColor() const
 {
-    if (mSelected == -1 || !userPalette)
+    if (mSelected == -1 || (userPalette == nullptr))
         return;
 
     const UserColorIdT type = static_cast<UserColorIdT>(
diff --git a/src/gui/widgets/tabs/setup_input.cpp b/src/gui/widgets/tabs/setup_input.cpp
index 2b7c4bedd..dc1e531f8 100644
--- a/src/gui/widgets/tabs/setup_input.cpp
+++ b/src/gui/widgets/tabs/setup_input.cpp
@@ -91,7 +91,7 @@ Setup_Input::Setup_Input(const Widget2 *const widget) :
 
     mKeyListModel->setSize(mActionDataSize[0]);
     refreshKeys();
-    if (gui)
+    if (gui != nullptr)
         mKeyList->setFont(gui->getHelpFont());
     mKeyList->addActionListener(this);
 
@@ -106,7 +106,7 @@ Setup_Input::Setup_Input(const Widget2 *const widget) :
     mTabs->addActionListener(this);
     mTabs->setActionEventId("tabs_");
     int k = 0;
-    while (pages[k])
+    while (pages[k] != nullptr)
     {
         mTabs->addButton(gettext(pages[k]), pages[k], false);
         k ++;
@@ -257,13 +257,13 @@ void Setup_Input::action(const ActionEvent &event)
     {
         int k = 0;
         std::string str("tabs_");
-        while (pages[k])
+        while (pages[k] != nullptr)
         {
             if (str + pages[k] == id)
                 break;
             k ++;
         }
-        if (pages[k] && str + pages[k] == id)
+        if ((pages[k] != nullptr) && str + pages[k] == id)
         {
             mKeyListModel->setSelectedData(k);
             mKeyListModel->setSize(mActionDataSize[k]);
diff --git a/src/gui/widgets/tabs/setup_joystick.cpp b/src/gui/widgets/tabs/setup_joystick.cpp
index 784197eb9..12cf331a0 100644
--- a/src/gui/widgets/tabs/setup_joystick.cpp
+++ b/src/gui/widgets/tabs/setup_joystick.cpp
@@ -73,7 +73,7 @@ Setup_Joystick::Setup_Joystick(const Widget2 *const widget) :
     mNamesDropDown->setActionEventId("name");
     mNamesDropDown->addActionListener(this);
 
-    if (joystick)
+    if (joystick != nullptr)
     {
         mNamesDropDown->setSelected(joystick->getNumber());
     }
@@ -113,12 +113,12 @@ void Setup_Joystick::action(const ActionEvent &event)
     }
     else if (source == mNamesDropDown)
     {
-        if (joystick)
+        if (joystick != nullptr)
             joystick->setNumber(mNamesDropDown->getSelected());
     }
     else if (source == mDetectButton)
     {
-        if (joystick)
+        if (joystick != nullptr)
         {
             joystick->reload();
             Joystick::getNames(mNamesModel->getNames());
@@ -127,7 +127,7 @@ void Setup_Joystick::action(const ActionEvent &event)
     }
     else
     {
-        if (!joystick)
+        if (joystick == nullptr)
             return;
 
         if (joystick->isCalibrating())
@@ -155,7 +155,7 @@ void Setup_Joystick::setTempEnabled(const bool sel)
 {
     Joystick::setEnabled(sel);
     mCalibrateButton->setEnabled(sel);
-    if (joystick)
+    if (joystick != nullptr)
     {
         if (sel)
             joystick->open();
@@ -166,7 +166,7 @@ void Setup_Joystick::setTempEnabled(const bool sel)
 
 void Setup_Joystick::cancel()
 {
-    if (joystick)
+    if (joystick != nullptr)
         joystick->setEnabled(mOriginalJoystickEnabled);
 
     if (mOriginalJoystickEnabled != mJoystickEnabled->isSelected())
@@ -177,7 +177,7 @@ void Setup_Joystick::cancel()
 
 void Setup_Joystick::apply()
 {
-    if (!joystick)
+    if (joystick == nullptr)
         return;
 
     config.setValue("joystickEnabled", joystick->isEnabled());
diff --git a/src/gui/widgets/tabs/setup_mods.cpp b/src/gui/widgets/tabs/setup_mods.cpp
index 994001763..7ee8f2f34 100644
--- a/src/gui/widgets/tabs/setup_mods.cpp
+++ b/src/gui/widgets/tabs/setup_mods.cpp
@@ -82,7 +82,7 @@ void Setup_Mods::loadMods()
     FOR_EACH (ModInfoCIterator, it, mods)
     {
         const ModInfo *const info = (*it).second;
-        if (!info)
+        if (info == nullptr)
             continue;
 
         std::string name = info->getName();
@@ -108,7 +108,7 @@ void Setup_Mods::saveMods() const
     FOR_EACH (std::set<SetupItem*>::const_iterator, it, modsList)
     {
         const SetupItem *const item = *it;
-        if (!item)
+        if (item == nullptr)
             continue;
         const std::string val = item->getValue();
         if (val == "1")
diff --git a/src/gui/widgets/tabs/setup_players.cpp b/src/gui/widgets/tabs/setup_players.cpp
index cca3acee9..4f9d8f856 100644
--- a/src/gui/widgets/tabs/setup_players.cpp
+++ b/src/gui/widgets/tabs/setup_players.cpp
@@ -186,6 +186,6 @@ void Setup_Players::externalUpdated()
 void Setup_Players::apply()
 {
     SetupTabScroll::apply();
-    settings.enableRemoteCommands = serverConfig.getValue(
-        "enableRemoteCommands", 1);
+    settings.enableRemoteCommands = (serverConfig.getValue(
+        "enableRemoteCommands", 1) != 0);
 }
diff --git a/src/gui/widgets/tabs/setup_relations.cpp b/src/gui/widgets/tabs/setup_relations.cpp
index 0054da32b..d81bca9a9 100644
--- a/src/gui/widgets/tabs/setup_relations.cpp
+++ b/src/gui/widgets/tabs/setup_relations.cpp
@@ -70,10 +70,10 @@ Setup_Relations::Setup_Relations(const Widget2 *const widget) :
     mPlayerScrollArea(new ScrollArea(this, mPlayerTable)),
     // TRANSLATORS: relation dialog button
     mDefaultTrading(new CheckBox(this, _("Allow trading"),
-        player_relations.getDefault() & PlayerRelation::TRADE)),
+        (player_relations.getDefault() & PlayerRelation::TRADE) != 0u)),
     // TRANSLATORS: relation dialog button
     mDefaultWhisper(new CheckBox(this, _("Allow whispers"),
-       player_relations.getDefault() & PlayerRelation::WHISPER)),
+       (player_relations.getDefault() & PlayerRelation::WHISPER) != 0u)),
     // TRANSLATORS: relation dialog button
     mDeleteButton(new Button(this, _("Delete"), ACTION_DELETE, this)),
     mIgnoreActionChoicesModel(new IgnoreChoicesListModel),
@@ -112,7 +112,7 @@ Setup_Relations::Setup_Relations(const Widget2 *const widget) :
 
     int ignore_strategy_index = 0;  // safe default
 
-    if (player_relations.getPlayerIgnoreStrategy())
+    if (player_relations.getPlayerIgnoreStrategy() != nullptr)
     {
         ignore_strategy_index = player_relations.getPlayerIgnoreStrategyIndex(
             player_relations.getPlayerIgnoreStrategy()->mShortName);
@@ -177,10 +177,10 @@ void Setup_Relations::apply()
         | (mDefaultTrading->isSelected() ? PlayerRelation::TRADE : 0)
         | (mDefaultWhisper->isSelected() ? PlayerRelation::WHISPER : 0));
 
-    if (actorManager)
+    if (actorManager != nullptr)
         actorManager->updatePlayerNames();
 
-    if (localPlayer)
+    if (localPlayer != nullptr)
         localPlayer->setCheckNameSetting(true);
 }
 
@@ -231,10 +231,10 @@ void Setup_Relations::updatedPlayer(const std::string &name A_UNUSED)
 {
     mPlayerTableModel->playerRelationsUpdated();
     mDefaultTrading->setSelected(
-            player_relations.getDefault() & PlayerRelation::TRADE);
+            (player_relations.getDefault() & PlayerRelation::TRADE) != 0u);
     mDefaultWhisper->setSelected(
-            player_relations.getDefault() & PlayerRelation::WHISPER);
-    if (localPlayer)
+            (player_relations.getDefault() & PlayerRelation::WHISPER) != 0u);
+    if (localPlayer != nullptr)
         localPlayer->updateName();
 }
 
@@ -246,7 +246,7 @@ void Setup_Relations::updateAll()
     mPlayerTableModel = model;
     int ignore_strategy_index = 0;  // safe default
 
-    if (player_relations.getPlayerIgnoreStrategy())
+    if (player_relations.getPlayerIgnoreStrategy() != nullptr)
     {
         ignore_strategy_index = player_relations.getPlayerIgnoreStrategyIndex(
                 player_relations.getPlayerIgnoreStrategy()->mShortName);
@@ -260,7 +260,7 @@ void Setup_Relations::updateAll()
 void Setup_Relations::externalUpdated()
 {
     mDefaultTrading->setSelected(
-        player_relations.getDefault() & PlayerRelation::TRADE);
+        (player_relations.getDefault() & PlayerRelation::TRADE) != 0u);
     mDefaultWhisper->setSelected(
-        player_relations.getDefault() & PlayerRelation::WHISPER);
+        (player_relations.getDefault() & PlayerRelation::WHISPER) != 0u);
 }
diff --git a/src/gui/widgets/tabs/setup_theme.cpp b/src/gui/widgets/tabs/setup_theme.cpp
index c97f192a0..47cbb2b92 100644
--- a/src/gui/widgets/tabs/setup_theme.cpp
+++ b/src/gui/widgets/tabs/setup_theme.cpp
@@ -237,7 +237,7 @@ void Setup_Theme::updateInfo()
 {
     delete mInfo;
     mInfo = Theme::loadInfo(mTheme);
-    if (mInfo)
+    if (mInfo != nullptr)
     {
         // TRANSLATORS: theme name
         mThemeInfo = std::string(_("Name: ")).append(mInfo->name)
@@ -356,7 +356,7 @@ void Setup_Theme::apply()
     }
 
     config.setValue("selectedSkin", "");
-    if (config.getStringValue("theme") != mTheme && mInfo)
+    if (config.getStringValue("theme") != mTheme && (mInfo != nullptr))
     {
         updateField(font, mFont);
         updateField(boldFont, mBoldFont);
@@ -366,13 +366,13 @@ void Setup_Theme::apply()
         updateField(npcFont, mNpcFont);
         updateField(japanFont, mJapanFont);
         updateField(chinaFont, mChinaFont);
-        if (mInfo->fontSize)
+        if (mInfo->fontSize != 0)
         {
             const int size = mInfo->fontSize - 9;
             if (size >= 0)
                 mFontSizeDropDown->setSelected(size);
         }
-        if (mInfo->npcfontSize)
+        if (mInfo->npcfontSize != 0)
         {
             const int size = mInfo->npcfontSize - 9;
             if (size >= 0)
diff --git a/src/gui/widgets/tabs/setup_video.cpp b/src/gui/widgets/tabs/setup_video.cpp
index 24fa8951f..b11b20f39 100644
--- a/src/gui/widgets/tabs/setup_video.cpp
+++ b/src/gui/widgets/tabs/setup_video.cpp
@@ -360,7 +360,7 @@ void Setup_Video::action(const ActionEvent &event)
 
         if (mode == "custom")
         {
-            if (mDialog)
+            if (mDialog != nullptr)
             {
                 mode = mDialog->getText();
                 mDialog = nullptr;
@@ -379,7 +379,7 @@ void Setup_Video::action(const ActionEvent &event)
         }
         const int width = atoi(mode.substr(0, mode.find('x')).c_str());
         const int height = atoi(mode.substr(mode.find('x') + 1).c_str());
-        if (!width || !height)
+        if ((width == 0) || (height == 0))
             return;
 
         if (width != mainGraphics->mActualWidth
@@ -491,7 +491,7 @@ void Setup_Video::action(const ActionEvent &event)
     else if (id == "detect")
     {
         TestMain *test = graphicsManager.startDetection();
-        if (test)
+        if (test != nullptr)
         {
             Configuration &conf = test->getConfig();
             const int val = conf.getValueInt("opengl", -1);
diff --git a/src/gui/widgets/tabs/setuptabscroll.cpp b/src/gui/widgets/tabs/setuptabscroll.cpp
index 898db7b3e..0cb623687 100644
--- a/src/gui/widgets/tabs/setuptabscroll.cpp
+++ b/src/gui/widgets/tabs/setuptabscroll.cpp
@@ -72,7 +72,7 @@ void SetupTabScroll::clear()
 
 void SetupTabScroll::addControl(SetupItem *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
     const std::string actionId = widget->getActionEventId();
     if (!actionId.empty())
@@ -109,7 +109,7 @@ void SetupTabScroll::apply()
          iter = mItems.begin(), iter_end = mItems.end();
          iter != iter_end; ++ iter)
     {
-        if ((*iter).second)
+        if ((*iter).second != nullptr)
             (*iter).second->apply((*iter).first);
     }
 }
@@ -120,7 +120,7 @@ void SetupTabScroll::cancel()
          iter = mItems.begin(), iter_end = mItems.end();
          iter != iter_end; ++ iter)
     {
-        if ((*iter).second)
+        if ((*iter).second != nullptr)
             (*iter).second->cancel((*iter).first);
     }
 }
@@ -132,7 +132,7 @@ void SetupTabScroll::externalUpdated()
          iter != iter_end; ++ iter)
     {
         SetupItem *const widget = (*iter).second;
-        if (widget && widget->isMainConfig() == MainConfig_false)
+        if ((widget != nullptr) && widget->isMainConfig() == MainConfig_false)
             widget->externalUpdated((*iter).first);
     }
 }
@@ -144,7 +144,7 @@ void SetupTabScroll::externalUnloaded()
          iter != iter_end; ++ iter)
     {
         SetupItem *const widget = (*iter).second;
-        if (widget && widget->isMainConfig() == MainConfig_false)
+        if ((widget != nullptr) && widget->isMainConfig() == MainConfig_false)
             widget->externalUnloaded((*iter).first);
     }
 }
@@ -158,6 +158,6 @@ void SetupTabScroll::widgetResized(const Event &event A_UNUSED)
 void SetupTabScroll::reread(const std::string &name)
 {
     SetupItem *const item = mItems[name + "Event"];
-    if (item)
+    if (item != nullptr)
         item->rereadValue();
 }
diff --git a/src/gui/widgets/tabs/skilltab.h b/src/gui/widgets/tabs/skilltab.h
index 3845444d6..9086a4d0c 100644
--- a/src/gui/widgets/tabs/skilltab.h
+++ b/src/gui/widgets/tabs/skilltab.h
@@ -65,9 +65,9 @@ class SkillTab final : public Tab
 
         SkillInfo *getSelectedInfo() const
         {
-            if (mListBox)
+            if (mListBox != nullptr)
                 return mListBox->getSelectedInfo();
-            else if (mRectangleListBox)
+            else if (mRectangleListBox != nullptr)
                 return mRectangleListBox->getSelectedInfo();
             else
                 return nullptr;
@@ -76,7 +76,7 @@ class SkillTab final : public Tab
     protected:
         void setCurrent() override
         {
-            if (skillDialog)
+            if (skillDialog != nullptr)
                 skillDialog->updateTabSelection();
         }
 
diff --git a/src/gui/widgets/tabs/socialfriendsfunctor.h b/src/gui/widgets/tabs/socialfriendsfunctor.h
index a15f566d6..e68647a77 100644
--- a/src/gui/widgets/tabs/socialfriendsfunctor.h
+++ b/src/gui/widgets/tabs/socialfriendsfunctor.h
@@ -35,11 +35,14 @@ class SortFriendsFunctor final
         bool operator() (const Avatar *const m1,
                          const Avatar *const m2) const
         {
-            if (!m1 || !m2)
+            if ((m1 == nullptr) || (m2 == nullptr))
                 return false;
 
             if (m1->getOnline() != m2->getOnline())
-                return m1->getOnline() > m2->getOnline();
+            {
+                return static_cast<int>(m1->getOnline()) >
+                    static_cast<int>(m2->getOnline());
+            }
 
             if (m1->getName() != m2->getName())
             {
diff --git a/src/gui/widgets/tabs/socialfriendstab.h b/src/gui/widgets/tabs/socialfriendstab.h
index 616fba43d..dfae61090 100644
--- a/src/gui/widgets/tabs/socialfriendstab.h
+++ b/src/gui/widgets/tabs/socialfriendstab.h
@@ -71,7 +71,7 @@ class SocialFriendsTab final : public SocialTab
 
         void getPlayersAvatars()
         {
-            if (!actorManager)
+            if (actorManager == nullptr)
                 return;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
@@ -90,7 +90,7 @@ class SocialFriendsTab final : public SocialTab
             const std::set<std::string> &players2
                 = whoIsOnline->getOnlineNicks();
 
-            if (!players)
+            if (players == nullptr)
                 return;
 
             int online = 0;
@@ -99,8 +99,8 @@ class SocialFriendsTab final : public SocialTab
             FOR_EACHP (StringVectCIter, it, players)
             {
                 Avatar *const ava = new Avatar(*it);
-                if (actorManager->findBeingByName(*it, ActorType::Player)
-                    || players2.find(*it) != players2.end())
+                if (actorManager->findBeingByName(*it, ActorType::Player) !=
+                    nullptr || players2.find(*it) != players2.end())
                 {
                     ava->setOnline(true);
                     online ++;
diff --git a/src/gui/widgets/tabs/socialguildtab.h b/src/gui/widgets/tabs/socialguildtab.h
index 53b7d46f4..775e22c6f 100644
--- a/src/gui/widgets/tabs/socialguildtab.h
+++ b/src/gui/widgets/tabs/socialguildtab.h
@@ -78,7 +78,7 @@ class SocialGuildTab final : public SocialTab,
                 const std::string name = mInviteDialog->getText();
                 guildHandler->invite(name);
 
-                if (localChatTab)
+                if (localChatTab != nullptr)
                 {
                     localChatTab->chatLog(strprintf(
                         // TRANSLATORS: chat message
@@ -96,7 +96,7 @@ class SocialGuildTab final : public SocialTab,
             else if (eventId == "yes")
             {
                 guildHandler->leave(mGuild->getId());
-                if (localChatTab)
+                if (localChatTab != nullptr)
                 {
                     localChatTab->chatLog(strprintf(
                         // TRANSLATORS: chat message
@@ -137,7 +137,7 @@ class SocialGuildTab final : public SocialTab,
 
         void buildCounter(const int online0, const int total0) override final
         {
-            if (online0 || total0)
+            if ((online0 != 0) || (total0 != 0))
             {
                 // TRANSLATORS: social window label
                 mCounterString = strprintf(_("Members: %u/%u"),
@@ -146,11 +146,11 @@ class SocialGuildTab final : public SocialTab,
             }
             else
             {
-                if (!localPlayer)
+                if (localPlayer == nullptr)
                     return;
 
                 const Guild *const guild = localPlayer->getGuild();
-                if (!guild)
+                if (guild == nullptr)
                     return;
 
                 const Guild::MemberList *const members = guild->getMembers();
diff --git a/src/gui/widgets/tabs/socialguildtab2.h b/src/gui/widgets/tabs/socialguildtab2.h
index a21594aab..f26e99421 100644
--- a/src/gui/widgets/tabs/socialguildtab2.h
+++ b/src/gui/widgets/tabs/socialguildtab2.h
@@ -77,11 +77,11 @@ class SocialGuildTab2 final : public SocialTab,
         void buildCounter(const int online0 A_UNUSED,
                           const int total0 A_UNUSED) override final
         {
-            if (!localPlayer)
+            if (localPlayer == nullptr)
                 return;
 
             const Guild *const guild = localPlayer->getGuild();
-            if (!guild)
+            if (guild == nullptr)
                 return;
 
             const Guild::MemberList *const members = guild->getMembers();
diff --git a/src/gui/widgets/tabs/socialnavigationtab.h b/src/gui/widgets/tabs/socialnavigationtab.h
index 0f72b60f9..80b5910f3 100644
--- a/src/gui/widgets/tabs/socialnavigationtab.h
+++ b/src/gui/widgets/tabs/socialnavigationtab.h
@@ -72,11 +72,11 @@ class SocialNavigationTab final : public SocialTab
 
         void updateList() override final
         {
-            if (!socialWindow || !localPlayer)
+            if ((socialWindow == nullptr) || (localPlayer == nullptr))
                 return;
 
             const Map *const map = socialWindow->getMap();
-            if (!map || map->empty())
+            if ((map == nullptr) || map->empty())
                 return;
 
             if (socialWindow->getProcessedPortals())
@@ -105,7 +105,7 @@ class SocialNavigationTab final : public SocialTab
             while (i != portals.end())
             {
                 MapItem *portal = *i;
-                if (!portal)
+                if (portal == nullptr)
                     continue;
 
                 const int x = portal->getX();
@@ -115,7 +115,7 @@ class SocialNavigationTab final : public SocialTab
                     portal->getComment().c_str(), x, y);
 
                 Avatar *const ava = new Avatar(name);
-                if (localPlayer)
+                if (localPlayer != nullptr)
                     ava->setOnline(localPlayer->isReachable(x, y, true));
                 else
                     ava->setOnline(false);
@@ -130,21 +130,21 @@ class SocialNavigationTab final : public SocialTab
                 total ++;
 
                 if (config.getBoolValue("drawHotKeys")
-                    && idx < 80 && outfitWindow)
+                    && idx < 80 && (outfitWindow != nullptr))
                 {
                     Being *const being = actorManager
                         ->findPortalByTile(x, y);
-                    if (being)
+                    if (being != nullptr)
                     {
                         being->setName(keyboard.getKeyShortString(
                             outfitWindow->keyName(idx)));
                     }
 
-                    if (specialLayer)
+                    if (specialLayer != nullptr)
                     {
                         portal = specialLayer->getTile(
                             ava->getX(), ava->getY());
-                        if (portal)
+                        if (portal != nullptr)
                         {
                             portal->setName(keyboard.getKeyShortString(
                                 outfitWindow->keyName(idx)));
@@ -155,7 +155,7 @@ class SocialNavigationTab final : public SocialTab
                 ++i;
                 idx ++;
             }
-            if (socialWindow)
+            if (socialWindow != nullptr)
                 socialWindow->setProcessedPortals(true);
 
             // TRANSLATORS: social window label
@@ -167,7 +167,7 @@ class SocialNavigationTab final : public SocialTab
 
         void selectIndex(const unsigned num) override final
         {
-            if (!localPlayer)
+            if (localPlayer == nullptr)
                 return;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
@@ -175,19 +175,19 @@ class SocialNavigationTab final : public SocialTab
                 return;
 
             const Avatar *const ava = avatars->at(num);
-            if (ava && localPlayer)
+            if ((ava != nullptr) && (localPlayer != nullptr))
                 localPlayer->navigateTo(ava->getX(), ava->getY());
         }
 
         void updateNames()
         {
-            if (!socialWindow)
+            if (socialWindow == nullptr)
                 return;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
 
             const Map *const map = socialWindow->getMap();
-            if (!map)
+            if (map == nullptr)
                 return;
 
             std::vector<Avatar*>::const_iterator i = avatars->begin();
@@ -195,12 +195,12 @@ class SocialNavigationTab final : public SocialTab
             while (i != i_end)
             {
                 Avatar *const ava = *i;
-                if (!ava)
+                if (ava == nullptr)
                     break;
 
                 const  MapItem *const item = map->findPortalXY(
                     ava->getX(), ava->getY());
-                if (item)
+                if (item != nullptr)
                 {
                     const std::string name = strprintf("%s [%d %d]",
                         item->getComment().c_str(),
@@ -215,12 +215,12 @@ class SocialNavigationTab final : public SocialTab
 
         int getPortalIndex(const int x, const int y)
         {
-            if (!socialWindow)
+            if (socialWindow == nullptr)
                 return -1;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
             const Map *const map = socialWindow->getMap();
-            if (!map)
+            if (map == nullptr)
                 return -1;
 
             std::vector<Avatar*>::const_iterator i = avatars->begin();
@@ -229,7 +229,7 @@ class SocialNavigationTab final : public SocialTab
             while (i != i_end)
             {
                 const Avatar *const ava = *i;
-                if (!ava)
+                if (ava == nullptr)
                     break;
 
                 if (ava->getX() == x && ava->getY() == y)
@@ -243,23 +243,23 @@ class SocialNavigationTab final : public SocialTab
 
         void addPortal(const int x, const int y)
         {
-            if (!socialWindow || !localPlayer)
+            if ((socialWindow == nullptr) || (localPlayer == nullptr))
                 return;
 
             const Map *const map = socialWindow->getMap();
-            if (!map)
+            if (map == nullptr)
                 return;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
             const MapItem *const portal = map->findPortalXY(x, y);
-            if (!portal)
+            if (portal == nullptr)
                 return;
 
             const std::string name = strprintf("%s [%d %d]",
                 portal->getComment().c_str(), x, y);
 
             Avatar *const ava = new Avatar(name);
-            if (localPlayer)
+            if (localPlayer != nullptr)
                 ava->setOnline(localPlayer->isReachable(x, y, true));
             else
                 ava->setOnline(false);
@@ -272,11 +272,11 @@ class SocialNavigationTab final : public SocialTab
 
         void removePortal(const int x, const int y)
         {
-            if (!socialWindow || !localPlayer)
+            if ((socialWindow == nullptr) || (localPlayer == nullptr))
                 return;
 
             const Map *const map = socialWindow->getMap();
-            if (!map)
+            if (map == nullptr)
                 return;
 
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
@@ -287,7 +287,7 @@ class SocialNavigationTab final : public SocialTab
             {
                 Avatar *ava = (*i);
 
-                if (!ava)
+                if (ava == nullptr)
                     break;
 
                 if (ava->getX() == x && ava->getY() == y)
diff --git a/src/gui/widgets/tabs/socialpartytab.h b/src/gui/widgets/tabs/socialpartytab.h
index 93625f7eb..b24f8f411 100644
--- a/src/gui/widgets/tabs/socialpartytab.h
+++ b/src/gui/widgets/tabs/socialpartytab.h
@@ -80,7 +80,7 @@ class SocialPartyTab final : public SocialTab,
                 const std::string name = mInviteDialog->getText();
                 partyHandler->invite(name);
 
-                if (localChatTab)
+                if (localChatTab != nullptr)
                 {
                     localChatTab->chatLog(strprintf(
                         // TRANSLATORS: chat message
@@ -97,7 +97,7 @@ class SocialPartyTab final : public SocialTab,
             else if (eventId == "yes")
             {
                 partyHandler->leave();
-                if (localChatTab)
+                if (localChatTab != nullptr)
                 {
                     localChatTab->chatLog(strprintf(
                         // TRANSLATORS: tab in social window
@@ -139,11 +139,11 @@ class SocialPartyTab final : public SocialTab,
         void buildCounter(const int online0 A_UNUSED,
                           const int total0 A_UNUSED) override final
         {
-            if (!localPlayer)
+            if (localPlayer == nullptr)
                 return;
 
             const Party *const party = localPlayer->getParty();
-            if (!party)
+            if (party == nullptr)
                 return;
 
             const Party::MemberList *const members = party->getMembers();
diff --git a/src/gui/widgets/tabs/socialplayerstab.h b/src/gui/widgets/tabs/socialplayerstab.h
index 2a80b3005..447e0791e 100644
--- a/src/gui/widgets/tabs/socialplayerstab.h
+++ b/src/gui/widgets/tabs/socialplayerstab.h
@@ -71,18 +71,18 @@ class SocialPlayersTab final : public SocialTab
 
         void updateAvatar(const std::string &name) override final
         {
-            if (!actorManager)
+            if (actorManager == nullptr)
                 return;
 
             BLOCK_START("SocialPlayersTab::updateAvatar")
             Avatar *const avatar = findAvatarbyName(name);
-            if (!avatar)
+            if (avatar == nullptr)
                 return;
-            if (Party::getParty(1))
+            if (Party::getParty(1) != nullptr)
             {
                 const PartyMember *const
                     pm = Party::getParty(1)->getMember(name);
-                if (pm && pm->getMaxHp() > 0)
+                if ((pm != nullptr) && pm->getMaxHp() > 0)
                 {
                     avatar->setMaxHp(pm->getMaxHp());
                     avatar->setHp(pm->getHp());
@@ -90,7 +90,7 @@ class SocialPlayersTab final : public SocialTab
             }
             const Being *const being = actorManager->findBeingByName(
                 name, ActorType::Player);
-            if (being)
+            if (being != nullptr)
             {
                 avatar->setDamageHp(being->getDamageTaken());
                 avatar->setLevel(being->getLevel());
@@ -103,17 +103,17 @@ class SocialPlayersTab final : public SocialTab
 
         void resetDamage(const std::string &name) override final
         {
-            if (!actorManager)
+            if (actorManager == nullptr)
                 return;
 
             Avatar *const avatar = findAvatarbyName(name);
-            if (!avatar)
+            if (avatar == nullptr)
                 return;
             avatar->setDamageHp(0);
             Being *const being = actorManager->findBeingByName(
                 name, ActorType::Player);
 
-            if (being)
+            if (being != nullptr)
                 being->setDamageTaken(0);
         }
 
@@ -126,7 +126,7 @@ class SocialPlayersTab final : public SocialTab
             while (i != i_end)
             {
                 ava = (*i);
-                if (ava && ava->getName() == name)
+                if ((ava != nullptr) && ava->getName() == name)
                     return ava;
                 ++i;
             }
@@ -139,7 +139,7 @@ class SocialPlayersTab final : public SocialTab
         void getPlayersAvatars()
         {
             std::vector<Avatar*> *const avatars = mBeings->getMembers();
-            if (actorManager)
+            if (actorManager != nullptr)
             {
                 StringVect names;
                 actorManager->getPlayerNames(names, NpcNames_false);
@@ -149,7 +149,7 @@ class SocialPlayersTab final : public SocialTab
                 {
                     bool finded = false;
                     const Avatar *const ava = (*ai);
-                    if (!ava)
+                    if (ava == nullptr)
                         break;
 
                     StringVectCIter i = names.begin();
diff --git a/src/gui/widgets/tabs/socialtab.h b/src/gui/widgets/tabs/socialtab.h
index 7458e62ee..34f864561 100644
--- a/src/gui/widgets/tabs/socialtab.h
+++ b/src/gui/widgets/tabs/socialtab.h
@@ -88,14 +88,14 @@ class SocialTab notfinal : public Tab
         virtual ~SocialTab()
         {
             // Cleanup dialogs
-            if (mInviteDialog)
+            if (mInviteDialog != nullptr)
             {
                 mInviteDialog->close();
                 mInviteDialog->scheduleDelete();
                 mInviteDialog = nullptr;
             }
 
-            if (mConfirmDialog)
+            if (mConfirmDialog != nullptr)
             {
                 mConfirmDialog->close();
                 mConfirmDialog->scheduleDelete();
@@ -122,13 +122,13 @@ class SocialTab notfinal : public Tab
 
         void updateCounter() const
         {
-            if (socialWindow)
+            if (socialWindow != nullptr)
                 socialWindow->updateCounter(this, mCounterString);
         }
 
         void updateMenu() const
         {
-            if (socialWindow)
+            if (socialWindow != nullptr)
                 socialWindow->updateMenu(this, mMenuAction);
         }
 
diff --git a/src/gui/widgets/tabs/tab.cpp b/src/gui/widgets/tabs/tab.cpp
index 95588e98d..a4a2f583b 100644
--- a/src/gui/widgets/tabs/tab.cpp
+++ b/src/gui/widgets/tabs/tab.cpp
@@ -130,11 +130,11 @@ Tab::Tab(const Widget2 *const widget) :
 
 Tab::~Tab()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     mInstances--;
-    if (mInstances == 0 && theme)
+    if (mInstances == 0 && (theme != nullptr))
     {
         for (int mode = 0; mode < TAB_COUNT; mode ++)
             theme->unload(tabImg[mode]);
@@ -142,7 +142,7 @@ Tab::~Tab()
 
     delete2(mLabel);
 
-    if (mImage)
+    if (mImage != nullptr)
     {
         mImage->decRef();
         mImage = nullptr;
@@ -162,7 +162,7 @@ void Tab::init()
     if (mInstances == 0)
     {
         // Load the skin
-        if (theme)
+        if (theme != nullptr)
         {
             for (int mode = 0; mode < TAB_COUNT; mode ++)
                 tabImg[mode] = theme->load(data[mode], "tab.xml");
@@ -174,7 +174,7 @@ void Tab::init()
     add(mLabel);
 
     const Skin *const skin = tabImg[TAB_STANDARD];
-    if (!skin)
+    if (skin == nullptr)
         return;
     const int padding = skin->getPadding();
 
@@ -194,11 +194,11 @@ void Tab::updateAlpha()
             for (int t = 0; t < TAB_COUNT; t++)
             {
                 Skin *const skin = tabImg[t];
-                if (skin)
+                if (skin != nullptr)
                 {
                     const ImageRect &rect = skin->getBorder();
                     Image *const image = rect.grid[a];
-                    if (image)
+                    if (image != nullptr)
                         image->setAlpha(mAlpha);
                 }
             }
@@ -212,7 +212,7 @@ void Tab::draw(Graphics *const graphics)
     int mode = TAB_STANDARD;
 
     // check which type of tab to draw
-    if (mTabbedArea)
+    if (mTabbedArea != nullptr)
     {
         int labelMode = mFlash;
 
@@ -223,7 +223,7 @@ void Tab::draw(Graphics *const graphics)
             // if tab is selected, it doesnt need to highlight activity
             mFlash = 0;
         }
-        else if (!labelMode)
+        else if (labelMode == 0)
         {
             if (mHasMouse)
             {
@@ -269,7 +269,7 @@ void Tab::draw(Graphics *const graphics)
     }
 
     const Skin *const skin = tabImg[mode];
-    if (!skin)
+    if (skin == nullptr)
     {
         BLOCK_END("Tab::draw")
         return;
@@ -288,10 +288,10 @@ void Tab::draw(Graphics *const graphics)
             mDimension.width, mDimension.height,
             rect);
 
-        if (mImage)
+        if (mImage != nullptr)
         {
             const Skin *const skin1 = tabImg[TAB_STANDARD];
-            if (skin1)
+            if (skin1 != nullptr)
             {
                 const int padding = skin1->getPadding();
                 graphics->calcTileCollection(mVertexes,
@@ -315,7 +315,7 @@ void Tab::safeDraw(Graphics *const graphics)
     int mode = TAB_STANDARD;
 
     // check which type of tab to draw
-    if (mTabbedArea)
+    if (mTabbedArea != nullptr)
     {
         int labelMode = mFlash;
 
@@ -326,7 +326,7 @@ void Tab::safeDraw(Graphics *const graphics)
             // if tab is selected, it doesnt need to highlight activity
             mFlash = 0;
         }
-        else if (!labelMode)
+        else if (labelMode == 0)
         {
             if (mHasMouse)
             {
@@ -370,7 +370,7 @@ void Tab::safeDraw(Graphics *const graphics)
     }
 
     const Skin *const skin = tabImg[mode];
-    if (!skin)
+    if (skin == nullptr)
     {
         BLOCK_END("Tab::draw")
         return;
@@ -381,10 +381,10 @@ void Tab::safeDraw(Graphics *const graphics)
     graphics->drawImageRect(0, 0,
         mDimension.width, mDimension.height,
         skin->getBorder());
-    if (mImage)
+    if (mImage != nullptr)
     {
         const Skin *const skin1 = tabImg[TAB_STANDARD];
-        if (skin1)
+        if (skin1 != nullptr)
         {
             const int padding = skin1->getPadding();
             graphics->drawImage(mImage, padding, padding);
@@ -407,7 +407,7 @@ void Tab::widgetMoved(const Event &event A_UNUSED)
 
 void Tab::setLabelFont(Font *const font)
 {
-    if (!mLabel)
+    if (mLabel == nullptr)
         return;
 
     mLabel->setFont(font);
@@ -420,11 +420,11 @@ void Tab::setLabelFont(Font *const font)
 void Tab::adjustSize()
 {
     const Skin *const skin = tabImg[TAB_STANDARD];
-    if (!skin)
+    if (skin == nullptr)
         return;
     const int pad2 = skin->getPadding() * 2;
 
-    if (mImage)
+    if (mImage != nullptr)
     {
         const SDL_Rect &rect = mImage->mBounds;
         setSize(rect.w + pad2, rect.h + pad2);
@@ -435,7 +435,7 @@ void Tab::adjustSize()
                 mLabel->getHeight() + pad2);
     }
 
-    if (mTabbedArea)
+    if (mTabbedArea != nullptr)
         mTabbedArea->adjustTabPositions();
 }
 
@@ -458,7 +458,7 @@ void Tab::setCaption(const std::string &caption)
 
 void Tab::setImage(Image *const image)
 {
-    if (mImage)
+    if (mImage != nullptr)
         mImage->decRef();
     mImage = image;
     adjustSize();
diff --git a/src/gui/widgets/tabstrip.cpp b/src/gui/widgets/tabstrip.cpp
index 1f8db0d5e..2a8299ea1 100644
--- a/src/gui/widgets/tabstrip.cpp
+++ b/src/gui/widgets/tabstrip.cpp
@@ -50,7 +50,7 @@ Widget *TabStrip::createWidget(const std::string &text,
     widget->setStick(true);
     widget->setCaption(text);
     widget->adjustSize();
-    if ((!mCount && mPressFirst) || pressed)
+    if (((mCount == 0) && mPressFirst) || pressed)
         widget->setPressed(true);
     widget->setTag(CAST_S32(mWidgets.size()));
     return widget;
@@ -59,11 +59,11 @@ Widget *TabStrip::createWidget(const std::string &text,
 void TabStrip::action(const ActionEvent &event)
 {
     WidgetGroup::action(event);
-    if (event.getSource())
+    if (event.getSource() != nullptr)
     {
         Widget *const widget = event.getSource();
         Button *const button = static_cast<Button*>(widget);
-        if (!button)
+        if (button == nullptr)
             return;
         if (button->isPressed2())
         {
diff --git a/src/gui/widgets/textbox.cpp b/src/gui/widgets/textbox.cpp
index 5b8acdb2e..31e000082 100644
--- a/src/gui/widgets/textbox.cpp
+++ b/src/gui/widgets/textbox.cpp
@@ -101,14 +101,14 @@ TextBox::TextBox(const Widget2 *const widget) :
 
 TextBox::~TextBox()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 }
 
 void TextBox::setTextWrapped(const std::string &text, const int minDimension)
 {
     // Make sure parent scroll area sets width of this widget
-    if (getParent())
+    if (getParent() != nullptr)
         getParent()->logic();
 
     // Take the supplied minimum dimension as a starting
@@ -384,7 +384,7 @@ void TextBox::keyPressed(KeyEvent& event)
         {
             Widget *const par = getParent();
 
-            if (par)
+            if (par != nullptr)
             {
                 const int rowsPerPage = par->getChildrenArea().height
                     / getFont()->getHeight();
@@ -400,7 +400,7 @@ void TextBox::keyPressed(KeyEvent& event)
         {
             Widget *const par = getParent();
 
-            if (par)
+            if (par != nullptr)
             {
                 const int rowsPerPage = par->getChildrenArea().height
                     / getFont()->getHeight();
@@ -605,7 +605,7 @@ void TextBox::mousePressed(MouseEvent& event)
     if (event.getButton() == MouseButton::LEFT)
     {
         const int height = getFont()->getHeight();
-        if (!height)
+        if (height == 0)
             return;
 
         event.consume();
diff --git a/src/gui/widgets/textfield.cpp b/src/gui/widgets/textfield.cpp
index ce37879a4..e536b5b13 100644
--- a/src/gui/widgets/textfield.cpp
+++ b/src/gui/widgets/textfield.cpp
@@ -123,7 +123,7 @@ TextField::TextField(const Widget2 *restrict const widget,
     mCaretColor(&getThemeColor(ThemeColorId::CARET)),
     mMinimum(0),
     mMaximum(0),
-    mLastEventPaste(false),
+    mLastEventPaste(0),
     mPadding(1),
     mNumeric(false),
     mLoseFocusOnTab(loseFocusOnTab),
@@ -144,7 +144,7 @@ TextField::TextField(const Widget2 *restrict const widget,
 
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             mSkin = theme->loadSkinRect(skin, "textfield.xml",
                 "textfield_background.xml");
@@ -153,7 +153,7 @@ TextField::TextField(const Widget2 *restrict const widget,
 
     instances++;
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mPadding = mSkin->getPadding();
         mFrameSize = mSkin->getOption("frameSize", 2);
@@ -163,22 +163,22 @@ TextField::TextField(const Widget2 *restrict const widget,
     if (!eventId.empty())
         setActionEventId(eventId);
 
-    if (listener)
+    if (listener != nullptr)
         addActionListener(listener);
 }
 
 TextField::~TextField()
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->removeWidgetListener(this);
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     instances--;
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
         {
             theme->unload(mSkin);
             Theme::unloadRect(skin);
@@ -197,7 +197,7 @@ void TextField::updateAlpha()
         mAlpha = alpha;
         for (int a = 0; a < 9; a++)
         {
-            if (skin.grid[a])
+            if (skin.grid[a] != nullptr)
                 skin.grid[a]->setAlpha(mAlpha);
         }
     }
@@ -227,7 +227,7 @@ void TextField::draw(Graphics *const graphics)
     }
 
     const Image *const image = mTextChunk.img;
-    if (image)
+    if (image != nullptr)
         graphics->drawImage(image, mPadding - mXScroll, mPadding);
 
     BLOCK_END("TextField::draw")
@@ -269,7 +269,7 @@ void TextField::setNumeric(const bool numeric)
         return;
 
     const char *const text = mText.c_str();
-    for (const char *textPtr = text; *textPtr; ++textPtr)
+    for (const char *textPtr = text; *textPtr != 0; ++textPtr)
     {
         if (*textPtr < '0' || *textPtr > '9')
         {
@@ -318,7 +318,8 @@ void TextField::keyPressed(KeyEvent &event)
     {
         if (mNumeric)
         {
-            if ((val >= '0' && val <= '9') || (val == '-' && !mCaretPosition))
+            if ((val >= '0' && val <= '9') ||
+                (val == '-' && mCaretPosition == 0u))
             {
                 char buf[2];
                 buf[0] = CAST_8(val);
@@ -333,7 +334,7 @@ void TextField::keyPressed(KeyEvent &event)
                 return;
             }
         }
-        else if (!mMaximum ||
+        else if ((mMaximum == 0) ||
                  CAST_S32(mText.size()) < mMaximum)
         {
             int len;
@@ -566,7 +567,7 @@ void TextField::handleCtrlKeys(const InputActionT action, bool &consumed)
 #else  // USE_SDL2
 
             // hack to prevent paste key sticking
-            if (mLastEventPaste && mLastEventPaste > cur_time)
+            if ((mLastEventPaste != 0) && mLastEventPaste > cur_time)
                 break;
             handlePaste();
             mLastEventPaste = cur_time + 2;
@@ -771,7 +772,7 @@ void TextField::mousePressed(MouseEvent &event)
     if (event.getButton() == MouseButton::RIGHT)
     {
 #ifndef DYECMD
-        if (popupMenu)
+        if (popupMenu != nullptr)
             popupMenu->showTextFieldPopup(this);
 #endif  // DYECMD
     }
@@ -817,14 +818,14 @@ void TextField::widgetHidden(const Event &event A_UNUSED)
 
 void TextField::setParent(Widget *widget)
 {
-    if (mWindow)
+    if (mWindow != nullptr)
         mWindow->addWidgetListener(this);
     Widget::setParent(widget);
 }
 
 void TextField::setWindow(Widget *const widget)
 {
-    if (!widget && mWindow)
+    if ((widget == nullptr) && (mWindow != nullptr))
     {
         mWindow->removeWidgetListener(this);
         mWindow = nullptr;
diff --git a/src/gui/widgets/textpreview.cpp b/src/gui/widgets/textpreview.cpp
index 04d2b39aa..53f84badc 100644
--- a/src/gui/widgets/textpreview.cpp
+++ b/src/gui/widgets/textpreview.cpp
@@ -55,13 +55,13 @@ TextPreview::TextPreview(const Widget2 *const widget,
     mAllowLogic = false;
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             mSkin = theme->load("textpreview.xml", "");
     }
 
     instances++;
 
-    if (mSkin)
+    if (mSkin != nullptr)
         mPadding = mSkin->getOption("padding", 0);
 
     adjustSize();
@@ -69,21 +69,21 @@ TextPreview::TextPreview(const Widget2 *const widget,
 
 TextPreview::~TextPreview()
 {
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
     instances--;
 
     if (instances == 0)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
     }
 }
 
 void TextPreview::draw(Graphics *const graphics)
 {
-    if (!mFont)
+    if (mFont == nullptr)
         return;
 
     BLOCK_START("TextPreview::draw")
@@ -103,7 +103,7 @@ void TextPreview::draw(Graphics *const graphics)
             mDimension.width, mDimension.height));
     }
 
-    if (mTextBGColor)
+    if (mTextBGColor != nullptr)
     {
         const int x = mFont->getWidth(mText) + 1
             + 2 * ((mOutline || mShadow) ? 1 :0);
diff --git a/src/gui/widgets/vertcontainer.cpp b/src/gui/widgets/vertcontainer.cpp
index 9aaad702d..e15dc2481 100644
--- a/src/gui/widgets/vertcontainer.cpp
+++ b/src/gui/widgets/vertcontainer.cpp
@@ -48,7 +48,7 @@ void VertContainer::add1(Widget *const widget, const int spacing)
 void VertContainer::add2(Widget *const widget, const bool resizable,
                          const int spacing)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     Container::add(widget);
diff --git a/src/gui/widgets/virtshortcutcontainer.cpp b/src/gui/widgets/virtshortcutcontainer.cpp
index dda7217c4..6b7642a3d 100644
--- a/src/gui/widgets/virtshortcutcontainer.cpp
+++ b/src/gui/widgets/virtshortcutcontainer.cpp
@@ -52,7 +52,7 @@ VirtShortcutContainer::VirtShortcutContainer(Widget2 *const widget,
     mUnEquipedColor2(getThemeColor(ThemeColorId::ITEM_NOT_EQUIPPED_OUTLINE)),
     mShortcut(shortcut)
 {
-    if (mShortcut)
+    if (mShortcut != nullptr)
         mMaxItems = mShortcut->getItemCount();
     else
         mMaxItems = 0;
@@ -73,21 +73,21 @@ void VirtShortcutContainer::setWidget2(const Widget2 *const widget)
 
 void VirtShortcutContainer::draw(Graphics *const graphics)
 {
-    if (!mShortcut)
+    if (mShortcut == nullptr)
         return;
 
     BLOCK_START("VirtShortcutContainer::draw")
     if (settings.guiAlpha != mAlpha)
     {
         mAlpha = settings.guiAlpha;
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
     }
 
     drawBackground(graphics);
 
     const Inventory *const inv = PlayerInfo::getInventory();
-    if (!inv)
+    if (inv == nullptr)
     {
         BLOCK_END("VirtShortcutContainer::draw")
         return;
@@ -106,12 +106,12 @@ void VirtShortcutContainer::draw(Graphics *const graphics)
         const Item *const item = inv->findItem(mShortcut->getItem(i),
             mShortcut->getItemColor(i));
 
-        if (item)
+        if (item != nullptr)
         {
             // Draw item icon.
             Image *const image = item->getImage();
 
-            if (image)
+            if (image != nullptr)
             {
                 std::string caption;
                 if (item->getQuantity() > 1)
@@ -147,21 +147,21 @@ void VirtShortcutContainer::draw(Graphics *const graphics)
 
 void VirtShortcutContainer::safeDraw(Graphics *const graphics)
 {
-    if (!mShortcut)
+    if (mShortcut == nullptr)
         return;
 
     BLOCK_START("VirtShortcutContainer::safeDraw")
     if (settings.guiAlpha != mAlpha)
     {
         mAlpha = settings.guiAlpha;
-        if (mBackgroundImg)
+        if (mBackgroundImg != nullptr)
             mBackgroundImg->setAlpha(mAlpha);
     }
 
     safeDrawBackground(graphics);
 
     const Inventory *const inv = PlayerInfo::getInventory();
-    if (!inv)
+    if (inv == nullptr)
     {
         BLOCK_END("VirtShortcutContainer::safeDraw")
         return;
@@ -180,12 +180,12 @@ void VirtShortcutContainer::safeDraw(Graphics *const graphics)
         const Item *const item = inv->findItem(mShortcut->getItem(i),
             mShortcut->getItemColor(i));
 
-        if (item)
+        if (item != nullptr)
         {
             // Draw item icon.
             Image *const image = item->getImage();
 
-            if (image)
+            if (image != nullptr)
             {
                 std::string caption;
                 if (item->getQuantity() > 1)
@@ -221,7 +221,7 @@ void VirtShortcutContainer::safeDraw(Graphics *const graphics)
 
 void VirtShortcutContainer::mouseDragged(MouseEvent &event)
 {
-    if (!mShortcut)
+    if (mShortcut == nullptr)
         return;
 
     if (event.getButton() == MouseButton::LEFT)
@@ -240,12 +240,12 @@ void VirtShortcutContainer::mouseDragged(MouseEvent &event)
                 return;
 
             const Inventory *const inv = PlayerInfo::getInventory();
-            if (!inv)
+            if (inv == nullptr)
                 return;
 
             Item *const item = inv->findItem(itemId, itemColor);
 
-            if (item)
+            if (item != nullptr)
             {
                 dragDrop.dragItem(item, DragDropSource::Drop);
                 mShortcut->removeItem(index);
@@ -260,7 +260,7 @@ void VirtShortcutContainer::mouseDragged(MouseEvent &event)
 
 void VirtShortcutContainer::mousePressed(MouseEvent &event)
 {
-    if (!mShortcut || !inventoryWindow)
+    if ((mShortcut == nullptr) || (inventoryWindow == nullptr))
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -290,13 +290,13 @@ void VirtShortcutContainer::mousePressed(MouseEvent &event)
     else if (eventButton == MouseButton::RIGHT)
     {
         const Inventory *const inv = PlayerInfo::getInventory();
-        if (!inv)
+        if (inv == nullptr)
             return;
 
         Item *const item = inv->findItem(mShortcut->getItem(index),
             mShortcut->getItemColor(index));
 
-        if (popupMenu)
+        if (popupMenu != nullptr)
         {
             popupMenu->showDropPopup(viewport->mMouseX,
                 viewport->mMouseY,
@@ -307,7 +307,7 @@ void VirtShortcutContainer::mousePressed(MouseEvent &event)
 
 void VirtShortcutContainer::mouseReleased(MouseEvent &event)
 {
-    if (!mShortcut)
+    if (mShortcut == nullptr)
         return;
 
     if (event.getButton() == MouseButton::LEFT)
@@ -339,7 +339,7 @@ void VirtShortcutContainer::mouseReleased(MouseEvent &event)
 // Show ItemTooltip
 void VirtShortcutContainer::mouseMoved(MouseEvent &event)
 {
-    if (!mShortcut)
+    if (mShortcut == nullptr)
         return;
 
     const int index = getIndexFromGrid(event.getX(), event.getY());
@@ -354,12 +354,12 @@ void VirtShortcutContainer::mouseMoved(MouseEvent &event)
         return;
 
     const Inventory *const inv = PlayerInfo::getInventory();
-    if (!inv)
+    if (inv == nullptr)
         return;
 
     const Item *const item = inv->findItem(itemId, itemColor);
 
-    if (item && viewport)
+    if ((item != nullptr) && (viewport != nullptr))
     {
         itemPopup->setItem(item, false);
         itemPopup->position(viewport->mMouseX, viewport->mMouseY);
@@ -372,12 +372,12 @@ void VirtShortcutContainer::mouseMoved(MouseEvent &event)
 
 void VirtShortcutContainer::mouseExited(MouseEvent &event A_UNUSED)
 {
-    if (itemPopup)
+    if (itemPopup != nullptr)
         itemPopup->setVisible(Visible_false);
 }
 
 void VirtShortcutContainer::widgetHidden(const Event &event A_UNUSED)
 {
-    if (itemPopup)
+    if (itemPopup != nullptr)
         itemPopup->setVisible(Visible_false);
 }
diff --git a/src/gui/widgets/widget.cpp b/src/gui/widgets/widget.cpp
index 9523cb4b5..260272936 100644
--- a/src/gui/widgets/widget.cpp
+++ b/src/gui/widgets/widget.cpp
@@ -179,7 +179,7 @@ void Widget::setDimension(const Rect& dimension)
 
 bool Widget::isFocused() const
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return false;
 
     return (mFocusHandler->isFocused(this));
@@ -187,7 +187,7 @@ bool Widget::isFocused() const
 
 void Widget::setFocusable(const bool focusable)
 {
-    if (!focusable && isFocused() && mFocusHandler)
+    if (!focusable && isFocused() && (mFocusHandler != nullptr))
         mFocusHandler->focusNone();
     mFocusable = focusable;
 }
@@ -199,7 +199,7 @@ bool Widget::isFocusable() const
 
 void Widget::requestFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
 
     if (isFocusable())
@@ -208,19 +208,19 @@ void Widget::requestFocus()
 
 void Widget::requestMoveToTop()
 {
-    if (mParent)
+    if (mParent != nullptr)
         mParent->moveToTop(this);
 }
 
 void Widget::requestMoveToBottom()
 {
-    if (mParent)
+    if (mParent != nullptr)
         mParent->moveToBottom(this);
 }
 
 void Widget::setVisible(Visible visible)
 {
-    if (visible == Visible_false && isFocused() && mFocusHandler)
+    if (visible == Visible_false && isFocused() && (mFocusHandler != nullptr))
         mFocusHandler->focusNone();
 
     if (visible == Visible_true)
@@ -233,13 +233,13 @@ void Widget::setVisible(Visible visible)
 
 void Widget::setFocusHandler(FocusHandler *const focusHandler)
 {
-    if (mFocusHandler)
+    if (mFocusHandler != nullptr)
     {
         releaseModalFocus();
         mFocusHandler->remove(this);
     }
 
-    if (focusHandler)
+    if (focusHandler != nullptr)
         focusHandler->add(this);
 
     mFocusHandler = focusHandler;
@@ -307,7 +307,7 @@ void Widget::removeWidgetListener(WidgetListener *const widgetListener)
 
 void Widget::getAbsolutePosition(int& x, int& y) const
 {
-    if (!mParent)
+    if (mParent == nullptr)
     {
         x = mDimension.x;
         y = mDimension.y;
@@ -326,7 +326,7 @@ void Widget::getAbsolutePosition(int& x, int& y) const
 
 Font* Widget::getFont() const
 {
-    if (!mCurrentFont)
+    if (mCurrentFont == nullptr)
         return mGlobalFont;
     return mCurrentFont;
 }
@@ -337,7 +337,7 @@ void Widget::setGlobalFont(Font *const font)
 
     FOR_EACH (std::list<Widget*>::const_iterator, iter, mAllWidgets)
     {
-        if (!(*iter)->mCurrentFont)
+        if ((*iter)->mCurrentFont == nullptr)
             (*iter)->fontChanged();
     }
 }
@@ -375,38 +375,38 @@ bool Widget::isEnabled() const
 
 void Widget::requestModalFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
     mFocusHandler->requestModalFocus(this);
 }
 
 void Widget::requestModalMouseInputFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
     mFocusHandler->requestModalMouseInputFocus(this);
 }
 
 void Widget::releaseModalFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
     mFocusHandler->releaseModalFocus(this);
 }
 
 void Widget::releaseModalMouseInputFocus()
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
     mFocusHandler->releaseModalMouseInputFocus(this);
 }
 
 bool Widget::isModalFocused() const
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return false;
 
-    if (mParent)
+    if (mParent != nullptr)
     {
         return (mFocusHandler->getModalFocused() == this)
             || mParent->isModalFocused();
@@ -417,10 +417,10 @@ bool Widget::isModalFocused() const
 
 bool Widget::isModalMouseInputFocused() const
 {
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return false;
 
-    if (mParent)
+    if (mParent != nullptr)
     {
         return (mFocusHandler->getModalMouseInputFocused() == this)
             || mParent->isModalMouseInputFocused();
@@ -506,7 +506,7 @@ void Widget::distributeShownEvent()
 
 void Widget::showPart(const Rect &rectangle)
 {
-    if (mParent)
+    if (mParent != nullptr)
         mParent->showWidgetPart(this, rectangle);
 }
 
@@ -517,7 +517,7 @@ void Widget::windowResized()
 
 Widget *Widget::callPostInit(Widget *const widget)
 {
-    if (widget)
+    if (widget != nullptr)
         widget->postInit();
     return widget;
 }
diff --git a/src/gui/widgets/widget.h b/src/gui/widgets/widget.h
index 2a8cae343..bbb1bc103 100644
--- a/src/gui/widgets/widget.h
+++ b/src/gui/widgets/widget.h
@@ -377,7 +377,7 @@ class Widget notfinal : public Widget2
         bool isVisible() const A_WARN_UNUSED
         {
             return mVisible == Visible_true &&
-                (!mParent || mParent->isVisible());
+                ((mParent == nullptr) || mParent->isVisible());
         }
 
         /**
diff --git a/src/gui/widgets/widget2.h b/src/gui/widgets/widget2.h
index d76bd696e..ed9110ba4 100644
--- a/src/gui/widgets/widget2.h
+++ b/src/gui/widgets/widget2.h
@@ -52,7 +52,7 @@ class Widget2 notfinal
                                               bool &valid)
                                               const A_WARN_UNUSED A_INLINE
         {
-            if (!theme)
+            if (theme == nullptr)
                 return Palette::BLACK;
             const ThemeColorIdT colorId = theme->getIdByChar(c, valid);
             if (valid)
@@ -63,7 +63,7 @@ class Widget2 notfinal
 
         virtual void setWidget2(const Widget2 *const widget)
         {
-            mPaletteOffset = widget ? widget->mPaletteOffset : 0;
+            mPaletteOffset = widget != nullptr ? widget->mPaletteOffset : 0;
         }
 
         void setPalette(int palette)
@@ -101,8 +101,8 @@ class Widget2 notfinal
 
     protected:
         explicit Widget2(const Widget2 *const widget) :
-            mPaletteOffset(widget ? widget->mPaletteOffset : 0),
-            mWindow(widget ? widget->getWindow() : nullptr),
+            mPaletteOffset(widget != nullptr ? widget->mPaletteOffset : 0),
+            mWindow(widget != nullptr ? widget->getWindow() : nullptr),
             mForegroundColor2()
         {
             checkPalette();
diff --git a/src/gui/widgets/widgetgroup.cpp b/src/gui/widgets/widgetgroup.cpp
index 18bd81a4f..72524b07c 100644
--- a/src/gui/widgets/widgetgroup.cpp
+++ b/src/gui/widgets/widgetgroup.cpp
@@ -46,7 +46,7 @@ void WidgetGroup::addButton(const std::string &restrict text,
         return;
 
     Widget *const widget = createWidget(text, pressed);
-    if (widget)
+    if (widget != nullptr)
     {
         widget->setActionEventId(mActionEventId + tag);
         widget->addActionListener(this);
@@ -66,7 +66,7 @@ void WidgetGroup::action(const ActionEvent &event)
 void WidgetGroup::addWidget(Widget *const widget,
                             const int spacing)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     Container::add(widget);
diff --git a/src/gui/widgets/window.cpp b/src/gui/widgets/window.cpp
index 86c2188d1..4a3103b99 100644
--- a/src/gui/widgets/window.cpp
+++ b/src/gui/widgets/window.cpp
@@ -180,10 +180,10 @@ Window::Window(const std::string &caption,
 
     int childPalette = 1;
     // Loads the skin
-    if (theme)
+    if (theme != nullptr)
     {
         mSkin = theme->load(skin, "window.xml");
-        if (mSkin)
+        if (mSkin != nullptr)
         {
             setPadding(mSkin->getPadding());
             if (getOptionBool("titlebarBold"))
@@ -191,10 +191,10 @@ Window::Window(const std::string &caption,
             mTitlePadding = mSkin->getTitlePadding();
             mGripPadding = getOption("resizePadding");
             mCaptionOffsetX = getOption("captionoffsetx");
-            if (!mCaptionOffsetX)
+            if (mCaptionOffsetX == 0)
                 mCaptionOffsetX = 7;
             mCaptionOffsetY = getOption("captionoffsety");
-            if (!mCaptionOffsetY)
+            if (mCaptionOffsetY == 0)
                 mCaptionOffsetY = 5;
             mCaptionAlign = static_cast<Graphics::Alignment>(
                 getOption("captionalign"));
@@ -205,7 +205,7 @@ Window::Window(const std::string &caption,
             }
             setTitleBarHeight(CAST_U32(
                 getOption("titlebarHeight")));
-            if (!mTitleBarHeight)
+            if (mTitleBarHeight == 0u)
                 mTitleBarHeight = mCaptionFont->getHeight() + mPadding;
 
             mTitleBarHeight += getOption("titlebarHeightRelative");
@@ -219,7 +219,7 @@ Window::Window(const std::string &caption,
     }
 
     // Add this window to the window container
-    if (windowContainer)
+    if (windowContainer != nullptr)
         windowContainer->add(this);
 
     if (mModal == Modal_true)
@@ -241,11 +241,11 @@ Window::~Window()
 {
     logger->log("Window::~Window(\"%s\")", getCaption().c_str());
 
-    if (gui)
+    if (gui != nullptr)
         gui->removeDragged(this);
 
 #ifndef DYECMD
-    if (setupWindow)
+    if (setupWindow != nullptr)
         setupWindow->unregisterWindowForReset(this);
 #endif  // DYECMD
 
@@ -265,13 +265,13 @@ Window::~Window()
 
     windowInstances--;
 
-    if (mSkin)
+    if (mSkin != nullptr)
     {
-        if (theme)
+        if (theme != nullptr)
             theme->unload(mSkin);
         mSkin = nullptr;
     }
-    if (mGrip)
+    if (mGrip != nullptr)
     {
         mGrip->decRef();
         mGrip = nullptr;
@@ -290,7 +290,7 @@ void Window::setWindowContainer(WindowContainer *const wc)
 
 void Window::draw(Graphics *const graphics)
 {
-    if (!mSkin)
+    if (mSkin == nullptr)
         return;
 
     BLOCK_START("Window::draw")
@@ -318,7 +318,7 @@ void Window::draw(Graphics *const graphics)
         {
             const Image *const button = mSkin->getCloseImage(
                 mResizeHandles == CLOSE);
-            if (button)
+            if (button != nullptr)
             {
                 graphics->calcTileCollection(mVertexes,
                     button,
@@ -330,7 +330,7 @@ void Window::draw(Graphics *const graphics)
         if (mStickyButton)
         {
             const Image *const button = mSkin->getStickyImage(mSticky);
-            if (button)
+            if (button != nullptr)
             {
                 graphics->calcTileCollection(mVertexes,
                     button,
@@ -339,7 +339,7 @@ void Window::draw(Graphics *const graphics)
             }
         }
 
-        if (mGrip)
+        if (mGrip != nullptr)
         {
             graphics->calcTileCollection(mVertexes,
                 mGrip,
@@ -383,7 +383,7 @@ void Window::draw(Graphics *const graphics)
         }
 
         const Image *const image = mTextChunk.img;
-        if (image)
+        if (image != nullptr)
             graphics->drawImage(image, x, mCaptionOffsetY);
     }
 
@@ -402,7 +402,7 @@ void Window::draw(Graphics *const graphics)
 
 void Window::safeDraw(Graphics *const graphics)
 {
-    if (!mSkin)
+    if (mSkin == nullptr)
         return;
 
     BLOCK_START("Window::safeDraw")
@@ -417,18 +417,18 @@ void Window::safeDraw(Graphics *const graphics)
     {
         const Image *const button = mSkin->getCloseImage(
             mResizeHandles == CLOSE);
-        if (button)
+        if (button != nullptr)
             graphics->drawImage(button, mCloseRect.x, mCloseRect.y);
     }
     // Draw Sticky Button
     if (mStickyButton)
     {
         const Image *const button = mSkin->getStickyImage(mSticky);
-        if (button)
+        if (button != nullptr)
             graphics->drawImage(button, mStickyRect.x, mStickyRect.y);
     }
 
-    if (mGrip)
+    if (mGrip != nullptr)
         graphics->drawImage(mGrip, mGripRect.x, mGripRect.y);
 
     // Draw title
@@ -460,7 +460,7 @@ void Window::safeDraw(Graphics *const graphics)
         }
 
         const Image *const image = mTextChunk.img;
-        if (image)
+        if (image != nullptr)
             graphics->drawImage(image, x, mCaptionOffsetY);
     }
 
@@ -488,7 +488,7 @@ void Window::setContentSize(int width, int height)
 
 void Window::setLocationRelativeTo(const Widget *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     int wx, wy;
@@ -505,7 +505,7 @@ void Window::setLocationRelativeTo(const Widget *const widget)
 
 void Window::setLocationHorisontallyRelativeTo(const Widget *const widget)
 {
-    if (!widget)
+    if (widget == nullptr)
         return;
 
     int wx, wy;
@@ -566,7 +566,7 @@ void Window::setLocationRelativeTo(const ImagePosition::Type &position,
 
 void Window::setMinWidth(const int width)
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mMinWinWidth = width > mSkin->getMinWidth()
             ? width : mSkin->getMinWidth();
@@ -579,7 +579,7 @@ void Window::setMinWidth(const int width)
 
 void Window::setMinHeight(const int height)
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         mMinWinHeight = height > mSkin->getMinHeight()
             ? height : mSkin->getMinHeight();
@@ -605,12 +605,12 @@ void Window::setResizable(const bool r)
     if ((mGrip != nullptr) == r)
         return;
 
-    if (mGrip)
+    if (mGrip != nullptr)
         mGrip->decRef();
     if (r)
     {
         mGrip = Theme::getImageFromThemeXml("resize.xml", "");
-        if (mGrip)
+        if (mGrip != nullptr)
         {
             mGripRect.x = mDimension.width - mGrip->getWidth() - mGripPadding;
             mGripRect.y = mDimension.height - mGrip->getHeight()
@@ -632,26 +632,26 @@ void Window::widgetResized(const Event &event A_UNUSED)
 {
     const Rect area = getChildrenArea();
 
-    if (mGrip)
+    if (mGrip != nullptr)
     {
         mGripRect.x = mDimension.width - mGrip->getWidth() - mGripPadding;
         mGripRect.y = mDimension.height - mGrip->getHeight() - mGripPadding;
     }
 
-    if (mLayout)
+    if (mLayout != nullptr)
     {
         int w = area.width;
         int h = area.height;
         mLayout->reflow(w, h);
     }
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         const bool showClose = mCloseWindowButton
-            && mSkin->getCloseImage(false);
+            && (mSkin->getCloseImage(false) != nullptr);
         if (showClose)
         {
             const Image *const button = mSkin->getCloseImage(false);
-            if (button)
+            if (button != nullptr)
             {
                 const int buttonWidth = button->getWidth();
                 mCloseRect.x = mDimension.width - buttonWidth - mClosePadding;
@@ -663,7 +663,7 @@ void Window::widgetResized(const Event &event A_UNUSED)
         if (mStickyButton)
         {
             const Image *const button = mSkin->getStickyImage(mSticky);
-            if (button)
+            if (button != nullptr)
             {
                 const int buttonWidth = button->getWidth();
                 int x = mDimension.width - buttonWidth
@@ -709,10 +709,10 @@ void Window::widgetHidden(const Event &event A_UNUSED)
     mTextChanged = true;
     mRedraw = true;
 
-    if (gui)
+    if (gui != nullptr)
         gui->setCursorType(Cursor::CURSOR_POINTER);
 
-    if (!mFocusHandler)
+    if (mFocusHandler == nullptr)
         return;
 
     for (WidgetListConstIterator it = mWidgets.begin();
@@ -732,7 +732,7 @@ void Window::setCloseButton(const bool flag)
 
 bool Window::isResizable() const
 {
-    return mGrip;
+    return mGrip != nullptr;
 }
 
 void Window::setStickyButton(const bool flag)
@@ -781,11 +781,11 @@ void Window::setVisible(const Visible visible, const bool forceSticky)
     {
         if (mPlayVisibleSound)
             soundManager.playGuiSound(SOUND_SHOW_WINDOW);
-        if (gui)
+        if (gui != nullptr)
         {
             MouseEvent *const event = reinterpret_cast<MouseEvent*>(
                 gui->createMouseEvent(this));
-            if (event)
+            if (event != nullptr)
             {
                 const int x = event->getX();
                 const int y = event->getY();
@@ -817,7 +817,7 @@ void Window::mousePressed(MouseEvent &event)
 
     if (event.getSource() == this)
     {
-        if (getParent())
+        if (getParent() != nullptr)
             getParent()->moveToTop(this);
 
         mDragOffsetX = event.getX();
@@ -832,21 +832,25 @@ void Window::mousePressed(MouseEvent &event)
         const int y = event.getY();
 
         // Handle close button
-        if (mCloseWindowButton && mSkin && mCloseRect.isPointInRect(x, y))
+        if (mCloseWindowButton &&
+            mSkin != nullptr &&
+            mCloseRect.isPointInRect(x, y))
         {
             mouseResize = 0;
-            mMoved = 0;
+            mMoved = false;
             event.consume();
             close();
             return;
         }
 
         // Handle sticky button
-        if (mStickyButton && mSkin && mStickyRect.isPointInRect(x, y))
+        if (mStickyButton &&
+            mSkin != nullptr &&
+            mStickyRect.isPointInRect(x, y))
         {
             setSticky(!isSticky());
             mouseResize = 0;
-            mMoved = 0;
+            mMoved = false;
             event.consume();
             return;
         }
@@ -856,14 +860,14 @@ void Window::mousePressed(MouseEvent &event)
         if (mouseResize != 0)
             event.consume();
         if (canMove())
-            mMoved = !mouseResize;
+            mMoved = (mouseResize == 0);
         else
             mMoved = false;
     }
 #ifndef DYECMD
     else if (button == MouseButton::RIGHT)
     {
-        if (popupMenu)
+        if (popupMenu != nullptr)
         {
             event.consume();
             popupMenu->showWindowPopup(this);
@@ -879,10 +883,10 @@ void Window::close()
 
 void Window::mouseReleased(MouseEvent &event A_UNUSED)
 {
-    if (mGrip && mouseResize)
+    if ((mGrip != nullptr) && (mouseResize != 0))
     {
         mouseResize = 0;
-        if (gui)
+        if (gui != nullptr)
             gui->setCursorType(Cursor::CURSOR_POINTER);
     }
 
@@ -896,13 +900,13 @@ void Window::mouseEntered(MouseEvent &event)
 
 void Window::mouseExited(MouseEvent &event A_UNUSED)
 {
-    if (mGrip && !mouseResize && gui)
+    if ((mGrip != nullptr) && (mouseResize == 0) && (gui != nullptr))
         gui->setCursorType(Cursor::CURSOR_POINTER);
 }
 
 void Window::updateResizeHandler(MouseEvent &event)
 {
-    if (!gui)
+    if (gui == nullptr)
         return;
 
 #ifndef DYECMD
@@ -940,7 +944,7 @@ void Window::updateResizeHandler(MouseEvent &event)
 void Window::mouseMoved(MouseEvent &event)
 {
     updateResizeHandler(event);
-    if (popupManager && !event.isConsumed())
+    if ((popupManager != nullptr) && !event.isConsumed())
     {
         popupManager->hideBeingPopup();
         popupManager->hideTextPopup();
@@ -983,31 +987,31 @@ void Window::mouseDragged(MouseEvent &event)
             std::max(0, mDimension.y)));
     }
 
-    if (mouseResize && !mMoved)
+    if ((mouseResize != 0) && !mMoved)
     {
         const int dx = event.getX() - mDragOffsetX;
         const int dy = event.getY() - mDragOffsetY;
         Rect newDim = getDimension();
 
-        if (mouseResize & (TOP | BOTTOM))
+        if ((mouseResize & (TOP | BOTTOM)) != 0)
         {
             const int newHeight = newDim.height
-                + ((mouseResize & TOP) ? -dy : dy);
+                + ((mouseResize & TOP) != 0 ? -dy : dy);
             newDim.height = std::min(mMaxWinHeight,
                 std::max(mMinWinHeight, newHeight));
 
-            if (mouseResize & TOP)
+            if ((mouseResize & TOP) != 0)
                 newDim.y -= newDim.height - getHeight();
         }
 
-        if (mouseResize & (LEFT | RIGHT))
+        if ((mouseResize & (LEFT | RIGHT)) != 0)
         {
             const int newWidth = newDim.width
-                + ((mouseResize & LEFT) ? -dx : dx);
+                + ((mouseResize & LEFT) != 0 ? -dx : dx);
             newDim.width = std::min(mMaxWinWidth,
                 std::max(mMinWinWidth, newWidth));
 
-            if (mouseResize & LEFT)
+            if ((mouseResize & LEFT) != 0)
                 newDim.x -= newDim.width - mDimension.width;
         }
 
@@ -1028,10 +1032,10 @@ void Window::mouseDragged(MouseEvent &event)
             newDim.height = mainGraphics->mHeight - newDim.y;
 
         // Update mouse offset when dragging bottom or right border
-        if (mouseResize & BOTTOM)
+        if ((mouseResize & BOTTOM) != 0)
             mDragOffsetY += newDim.height - mDimension.height;
 
-        if (mouseResize & RIGHT)
+        if ((mouseResize & RIGHT) != 0)
             mDragOffsetX += newDim.width - mDimension.width;
 
         // Set the new window and content dimensions
@@ -1046,7 +1050,7 @@ void Window::setModal(const Modal modal)
         mModal = modal;
         if (mModal == Modal_true)
         {
-            if (gui)
+            if (gui != nullptr)
                 gui->setCursorType(Cursor::CURSOR_POINTER);
             requestModalFocus();
         }
@@ -1078,7 +1082,7 @@ void Window::loadWindowState()
             + "Sticky", isSticky()));
     }
 
-    if (mGrip)
+    if (mGrip != nullptr)
     {
         int width = config.getValueInt(name + "WinWidth", mDefaultWidth);
         int height = config.getValueInt(name + "WinHeight", mDefaultHeight);
@@ -1102,7 +1106,7 @@ void Window::loadWindowState()
     // Check if the window is off screen...
     ensureOnScreen();
 
-    if (viewport)
+    if (viewport != nullptr)
     {
         int width = mDimension.width;
         int height = mDimension.height;
@@ -1133,7 +1137,7 @@ void Window::saveWindowState()
         if (mStickyButton)
             config.setValue(mWindowName + "Sticky", isSticky());
 
-        if (mGrip)
+        if (mGrip != nullptr)
         {
             if (getMinWidth() > mDimension.width)
                 setWidth(getMinWidth());
@@ -1257,7 +1261,7 @@ void Window::adjustPositionAfterResize(const int oldScreenWidth,
 
 void Window::adjustSizeToScreen()
 {
-    if (!mGrip)
+    if (mGrip == nullptr)
         return;
 
     const int screenWidth = mainGraphics->mWidth;
@@ -1289,7 +1293,7 @@ int Window::getResizeHandles(const MouseEvent &event)
 
     if (!mStickyButtonLock || !mSticky)
     {
-        if (mGrip &&
+        if ((mGrip != nullptr) &&
             (y > mTitleBarHeight ||
             (CAST_S32(y) < mPadding &&
             CAST_S32(mTitleBarHeight) > mPadding)))
@@ -1319,7 +1323,7 @@ bool Window::isResizeAllowed(const MouseEvent &event) const
 {
     const int y = event.getY();
 
-    if (mGrip &&
+    if ((mGrip != nullptr) &&
         (y > CAST_S32(mTitleBarHeight) ||
         y < mPadding))
     {
@@ -1337,7 +1341,7 @@ bool Window::isResizeAllowed(const MouseEvent &event) const
 
 Layout &Window::getLayout()
 {
-    if (!mLayout)
+    if (mLayout == nullptr)
         mLayout = new Layout;
     return *mLayout;
 }
@@ -1347,7 +1351,7 @@ void Window::clearLayout()
     clear();
 
     // Recreate layout instance when one is present
-    if (mLayout)
+    if (mLayout != nullptr)
     {
         delete mLayout;
         mLayout = new Layout;
@@ -1368,7 +1372,7 @@ ContainerPlacer Window::getPlacer(const int x, const int y)
 
 void Window::reflowLayout(int w, int h)
 {
-    if (!mLayout)
+    if (mLayout == nullptr)
         return;
 
     mLayout->reflow(w, h);
@@ -1378,7 +1382,7 @@ void Window::reflowLayout(int w, int h)
 
 void Window::redraw()
 {
-    if (mLayout)
+    if (mLayout != nullptr)
     {
         const Rect area = getChildrenArea();
         int w = area.width;
@@ -1426,10 +1430,10 @@ Rect Window::getWindowArea() const
 
 int Window::getOption(const std::string &name, const int def) const
 {
-    if (mSkin)
+    if (mSkin != nullptr)
     {
         const int val = mSkin->getOption(name);
-        if (val)
+        if (val != 0)
             return val;
         return def;
     }
@@ -1438,8 +1442,8 @@ int Window::getOption(const std::string &name, const int def) const
 
 bool Window::getOptionBool(const std::string &name, const bool def) const
 {
-    if (mSkin)
-        return mSkin->getOption(name, def) != 0;
+    if (mSkin != nullptr)
+        return mSkin->getOption(name, static_cast<int>(def)) != 0;
     return def;
 }
 
diff --git a/src/gui/widgets/windowcontainer.cpp b/src/gui/widgets/windowcontainer.cpp
index 9529945b0..38efd1a77 100644
--- a/src/gui/widgets/windowcontainer.cpp
+++ b/src/gui/widgets/windowcontainer.cpp
@@ -44,7 +44,7 @@ void WindowContainer::slowLogic()
 
 void WindowContainer::scheduleDelete(Widget *const widget)
 {
-    if (widget)
+    if (widget != nullptr)
         mDeathList.push_back(widget);
 }