Added the ability to ask a ambient layer to keep its ratio when the resolution isn't the default.

You'll have to add this in map properties, for instance if you're want to keep ratio on overlay 0:
<map version="1.0" orientation="orthogonal" width="128" height="128" tilewidth="32" tileheight="32">
 <properties>
  ...
  <property name="overlay0keepratio" value="true"/>
  ...
 </properties>
</map>

2 files changed, 41 insertions, 6 deletions

diff --git a/src/resources/ambientoverlay.cpp b/src/resources/ambientoverlay.cpp
index 93c7c3e1..8c851e2e 100644
--- a/src/resources/ambientoverlay.cpp
+++ b/src/resources/ambientoverlay.cpp
@@ -22,16 +22,41 @@
 #include "resources/ambientoverlay.h"
 
 #include "resources/image.h"
-
+#include "resources/resourcemanager.h"
 #include "graphics.h"
 
 AmbientOverlay::AmbientOverlay(Image *img, float parallax,
-                               float speedX, float speedY):
+                               float speedX, float speedY, bool keepRatio):
     mImage(img), mParallax(parallax),
     mPosX(0), mPosY(0),
-    mSpeedX(speedX), mSpeedY(speedY)
+    mSpeedX(speedX), mSpeedY(speedY),
+    mKeepRatio(keepRatio)
 {
-    mImage->incRef();
+
+    if (keepRatio && !mImage->isAnOpenGLOne()
+        && defaultScreenWidth != 0
+        && defaultScreenHeight != 0
+        && graphics->getWidth() != defaultScreenWidth
+        && graphics->getHeight() != defaultScreenHeight)
+    {
+        // Rescale the overlay to keep the ratio as if we were on
+        // the default resolution...
+        Image *rescaledOverlay = mImage->SDLgetScaledImage(
+         (int) mImage->getWidth() / defaultScreenWidth * graphics->getWidth(),
+     (int) mImage->getHeight() / defaultScreenHeight * graphics->getHeight());
+
+        if (rescaledOverlay)
+        {
+            // Replace the resource with the new one...
+            std::string idPath = mImage->getIdPath() + "_rescaled";
+            ResourceManager::getInstance()->addResource(idPath, rescaledOverlay);
+            mImage = rescaledOverlay;
+        }
+        else
+            mImage->incRef();
+    }
+    else
+        mImage->incRef();
 }
 
 AmbientOverlay::~AmbientOverlay()
@@ -66,6 +91,13 @@ void AmbientOverlay::update(int timePassed, float dx, float dy)
 
 void AmbientOverlay::draw(Graphics *graphics, int x, int y)
 {
-    graphics->drawImagePattern(mImage,
+    if (!mImage->isAnOpenGLOne() || !mKeepRatio)
+        graphics->drawImagePattern(mImage,
             (int) -mPosX, (int) -mPosY, x + (int) mPosX, y + (int) mPosY);
+    else
+        graphics->drawRescaledImagePattern(mImage,
+              (int) -mPosX, (int) -mPosY, x + (int) mPosX, y + (int) mPosY,
+         (int) mImage->getWidth() / defaultScreenWidth * graphics->getWidth(),
+     (int) mImage->getHeight() / defaultScreenHeight * graphics->getHeight());
+
 }
diff --git a/src/resources/ambientoverlay.h b/src/resources/ambientoverlay.h
index 756d0eb7..f2d2e588 100644
--- a/src/resources/ambientoverlay.h
+++ b/src/resources/ambientoverlay.h
@@ -35,9 +35,11 @@ class AmbientOverlay
          * @param parallax  scroll factor based on camera position
          * @param speedX    scrolling speed in x-direction
          * @param speedY    scrolling speed in y-direction
+         * @param keepRatio  rescale the image to keep
+         * the same ratio than in 800x600 resolution mode.
          */
         AmbientOverlay(Image *img, float parallax,
-                       float speedX, float speedY);
+                       float speedX, float speedY, bool keepRatio = false);
 
         ~AmbientOverlay();
 
@@ -52,6 +54,7 @@ class AmbientOverlay
         float mPosY;              /**< Current layer Y position. */
         float mSpeedX;            /**< Scrolling speed in X direction. */
         float mSpeedY;            /**< Scrolling speed in Y direction. */
+        bool mKeepRatio;          /**< Keep overlay ratio on every resolution */
 };
 
 #endif