I want to use GL_UNSIGNED_SHORT for my texture coordinates (in pixels) but because I am using texture atlasses I need to modify the texture matrix rather than loop through all the vertex data and change the uv coords everytime I need to change the model's skin.
Say "imageRect" holds the dimentions of the image in the texture and textureSize is the size of the texture. Below is currently how I am setting the texture matrix but I am not getting the area of the texture I expect.
What are you getting? Is the resulting image stretched? Is it the right size, but coming from the wrong location? Is the y coordinate in m_imageRect relative to the top or bottom of the image, and how does that compare to the texture matrix translation?