PlatformImage: Take canvas' width into account on getRGB()

Serves me right for swapping WritableRasters for dataBuffers
without double-checking if the actual data copy needs any further
adjustments. Fixes smoke in Asphalt 4's SE K800i version, and
probably quite a few others games that rely on this function.

src/org/recompile/mobile/PlatformImage.java

@@ -239,7 +239,7 @@ public void getRGB(int[] rgbData, int offset, int scanlength, int x, int y, int
 		// Copy the data into rgbData, taking scanlength into account
 		for (int row = 0; row < height; row++) 
 		{
-			int sourceIndex = row * width;
+			int sourceIndex = (y + row) * canvas.getWidth() + x;
 			int destIndex = offset + row * scanlength;
 
 			System.arraycopy(tempData, sourceIndex, rgbData, destIndex, width);