diff options
Diffstat (limited to 'src/resources')
| -rw-r--r-- | src/resources/image.cpp | 100 | ||||
| -rw-r--r-- | src/resources/image.h | 13 |
2 files changed, 74 insertions, 39 deletions
diff --git a/src/resources/image.cpp b/src/resources/image.cpp index a9005509..877bb998 100644 --- a/src/resources/image.cpp +++ b/src/resources/image.cpp @@ -27,6 +27,7 @@ #include <SDL_image.h> #include "resources/sdlrescalefacility.h" +#include <assert.h> #ifdef USE_OPENGL bool Image::mUseOpenGL = false; @@ -34,9 +35,11 @@ int Image::mTextureType = 0; int Image::mTextureSize = 0; #endif -Image::Image(SDL_Surface *image): +Image::Image(SDL_Surface *image, bool hasAlphaChannel, Uint8 *alphaChannel): mAlpha(1.0f), - mSDLSurface(image) + mSDLSurface(image), + mHasAlphaChannel(hasAlphaChannel), + mAlphaChannel(alphaChannel) { #ifdef USE_OPENGL mGLImage = 0; @@ -52,7 +55,6 @@ Image::Image(SDL_Surface *image): mBounds.w = mSDLSurface->w; mBounds.h = mSDLSurface->h; - mHasAlphaChannel = hasAlphaChannel(); mLoaded = true; } else @@ -62,9 +64,10 @@ Image::Image(SDL_Surface *image): #ifdef USE_OPENGL Image::Image(GLuint glimage, int width, int height, int texWidth, int texHeight): - mAlpha(1.0), + mAlpha(1.0f), mHasAlphaChannel(true), mSDLSurface(0), + mAlphaChannel(0), mGLImage(glimage), mTexWidth(texWidth), mTexHeight(texHeight) @@ -169,6 +172,9 @@ void Image::unload() // Free the image surface. SDL_FreeSurface(mSDLSurface); mSDLSurface = NULL; + + delete[] mAlphaChannel; + mAlphaChannel = NULL; } #ifdef USE_OPENGL @@ -199,44 +205,49 @@ bool Image::hasAlphaChannel() return true; #endif - if (!mSDLSurface) - return false; + return false; +} - bool hasAlpha = false; +void Image::setAlpha(float alpha) +{ + if (mAlpha == alpha) + return; + + if (alpha < 0.0f || alpha > 1.0f) + return; - if (mSDLSurface->format->BitsPerPixel == 32) + mAlpha = alpha; + + if (mSDLSurface) { - // Figure out whether the image uses its alpha layer - for (int i = 0; i < mSDLSurface->w * mSDLSurface->h; ++i) + if (!hasAlphaChannel()) { - Uint8 r, g, b, a; - SDL_GetRGBA( - ((Uint32*) mSDLSurface->pixels)[i], - mSDLSurface->format, - &r, &g, &b, &a); - - if (a != 255) - { - hasAlpha = true; - break; - } + // Set the alpha value this image is drawn at + SDL_SetAlpha(mSDLSurface, SDL_SRCALPHA, (int) (255 * mAlpha)); } - } + else + { + if (SDL_MUSTLOCK(mSDLSurface)) + SDL_LockSurface(mSDLSurface); - return hasAlpha; -} + for (int i = 0; i < mSDLSurface->w * mSDLSurface->h; ++i) + { + Uint8 r, g, b, a; + SDL_GetRGBA( + ((Uint32*) mSDLSurface->pixels)[i], + mSDLSurface->format, + &r, &g, &b, &a); -void Image::setAlpha(float a) -{ - if (mAlpha == a) - return; + a = (Uint8) (mAlphaChannel[i] * mAlpha); - mAlpha = a; + // Here is the pixel we want to set + ((Uint32 *)(mSDLSurface->pixels))[i] = + SDL_MapRGBA(mSDLSurface->format, r, g, b, a); + } - if (mSDLSurface) - { - // Set the alpha value this image is drawn at - SDL_SetAlpha(mSDLSurface, SDL_SRCALPHA, (int) (255 * mAlpha)); + if (SDL_MUSTLOCK(mSDLSurface)) + SDL_UnlockSurface(mSDLSurface); + } } } @@ -353,6 +364,9 @@ Image *Image::_SDLload(SDL_Surface *tmpImage) bool hasAlpha = false; + // The alpha channel to be filled with alpha values + Uint8 *alphaChannel = new Uint8[tmpImage->w * tmpImage->h]; + if (tmpImage->format->BitsPerPixel == 32) { // Figure out whether the image uses its alpha layer @@ -365,10 +379,9 @@ Image *Image::_SDLload(SDL_Surface *tmpImage) &r, &g, &b, &a); if (a != 255) - { hasAlpha = true; - break; - } + + alphaChannel[i] = a; } } @@ -378,15 +391,23 @@ Image *Image::_SDLload(SDL_Surface *tmpImage) if (hasAlpha) image = SDL_DisplayFormatAlpha(tmpImage); else + { image = SDL_DisplayFormat(tmpImage); + // We also delete the alpha channel since + // it's not used. + delete[] alphaChannel; + alphaChannel = NULL; + } + if (!image) { logger->log("Error: Image convert failed."); + delete[] alphaChannel; return NULL; } - return new Image(image); + return new Image(image, hasAlpha, alphaChannel); } #ifdef USE_OPENGL @@ -537,6 +558,9 @@ SubImage::SubImage(Image *parent, SDL_Surface *image, { mParent->incRef(); + mHasAlphaChannel = mParent->hasAlphaChannel(); + mAlphaChannel = mParent->SDLgetAlphaChannel(); + // Set up the rectangle. mBounds.x = x; mBounds.y = y; @@ -565,6 +589,8 @@ SubImage::~SubImage() { // Avoid destruction of the image mSDLSurface = 0; + // Avoid possible destruction of its alpha channel + mAlphaChannel = 0; #ifdef USE_OPENGL mGLImage = 0; #endif diff --git a/src/resources/image.h b/src/resources/image.h index dfa319ab..9c0f9da7 100644 --- a/src/resources/image.h +++ b/src/resources/image.h @@ -118,7 +118,7 @@ class Image : public Resource /** * Tells if the image has got an alpha channel - * @return true if OpenGL, false if SDL. + * @return true if it's true, false otherwise. */ bool hasAlphaChannel(); @@ -163,6 +163,12 @@ class Image : public Resource */ Image *SDLmerge(Image *image, int x, int y); + /** + * Get the alpha Channel of a SDL surface. + */ + Uint8 *SDLgetAlphaChannel() const + { return mAlphaChannel; } + #ifdef USE_OPENGL // OpenGL only public functions @@ -194,13 +200,16 @@ class Image : public Resource // ----------------------- /** SDL Constructor */ - Image(SDL_Surface *image); + Image(SDL_Surface *image, bool hasAlphaChannel = false, + Uint8 *alphaChannel = NULL); /** SDL_Surface to SDL_Surface Image loader */ static Image *_SDLload(SDL_Surface *tmpImage); SDL_Surface *mSDLSurface; + /** Alpha Channel pointer used for 32bit based SDL surfaces */ + Uint8 *mAlphaChannel; // ----------------------- // OpenGL protected members |