1 files changed, 67 insertions, 0 deletions
diff --git a/src/openglgraphics.cpp b/src/openglgraphics.cpp
index b9d837ad..5c9e2049 100644
--- a/src/openglgraphics.cpp
+++ b/src/openglgraphics.cpp
@@ -140,6 +140,42 @@ static inline void drawQuad(Image *image,
     }
 }
 
+static inline void drawRescaledQuad(Image *image,
+                            int srcX, int srcY, int dstX, int dstY,
+                            int width, int height,
+                            int desiredWidth, int desiredHeight)
+{
+    if (image->getTextureType() == GL_TEXTURE_2D)
+    {
+        // Find OpenGL normalized texture coordinates.
+        float texX1 = srcX / (float) image->getTextureWidth();
+        float texY1 = srcY / (float) image->getTextureHeight();
+        float texX2 = (srcX + width) / (float) image->getTextureWidth();
+        float texY2 = (srcY + height) / (float) image->getTextureHeight();
+
+        glTexCoord2f(texX1, texY1);
+        glVertex2i(dstX, dstY);
+        glTexCoord2f(texX2, texY1);
+        glVertex2i(dstX + desiredWidth, dstY);
+        glTexCoord2f(texX2, texY2);
+        glVertex2i(dstX + desiredWidth, dstY + desiredHeight);
+        glTexCoord2f(texX1, texY2);
+        glVertex2i(dstX, dstY + desiredHeight);
+    }
+    else
+    {
+        glTexCoord2i(srcX, srcY);
+        glVertex2i(dstX, dstY);
+        glTexCoord2i(srcX + width, srcY);
+        glVertex2i(dstX + desiredWidth, dstY);
+        glTexCoord2i(srcX + width, srcY + height);
+        glVertex2i(dstX + desiredWidth, dstY + desiredHeight);
+        glTexCoord2i(srcX, srcY + height);
+        glVertex2i(dstX, dstY + desiredHeight);
+    }
+}
+
+
 bool OpenGLGraphics::drawImage(Image *image, int srcX, int srcY,
                                int dstX, int dstY,
                                int width, int height, bool useColor)
@@ -168,6 +204,37 @@ bool OpenGLGraphics::drawImage(Image *image, int srcX, int srcY,
     return true;
 }
 
+bool OpenGLGraphics::drawRescaledImage(Image *image, int srcX, int srcY,
+                               int dstX, int dstY,
+                               int width, int height,
+                               int desiredWidth, int desiredHeight,
+                               bool useColor)
+{
+    if (!image)
+        return false;
+
+    srcX += image->mBounds.x;
+    srcY += image->mBounds.y;
+
+    if (!useColor)
+        glColor4f(1.0f, 1.0f, 1.0f, image->mAlpha);
+
+    glBindTexture(Image::mTextureType, image->mGLImage);
+
+    setTexturingAndBlending(true);
+
+    // Draw a textured quad.
+    glBegin(GL_QUADS);
+    drawRescaledQuad(image, srcX, srcY, dstX, dstY, width, height,
+                     desiredWidth, desiredHeight);
+    glEnd();
+
+    if (!useColor)
+        glColor4ub(mColor.r, mColor.g, mColor.b, mColor.a);
+
+    return true;
+}
+
 /* Optimising the functions that Graphics::drawImagePattern would call,
  * so that glBegin...glEnd are outside the main loop. */
 void OpenGLGraphics::drawImagePattern(Image *image, int x, int y, int w, int h)