On 25/07/06, Jason Green <[EMAIL PROTECTED]> wrote:
current renderTarget is not on the current swapchain. The comments in the source say that the upside-downedness is produced by glCopyTexImage, so it sets a flag to flip everything over.
I don't think it's so much that glCopyTexImage flips the texture over, but rather the fact that OpenGL texture coordinates are flipped over the y-axis compared to Direct3D.
So, I think what we need to do is prevent ourselves from having to do any flipping whatsoever. That's the part that I'm not sure how to do and is the reason for this email. Can we load the textures in system memory first, perform a software reversing process, then load that up with glCopyTexImage instead? Will we need to do that type of fixup every time the app locks/unlocks/changes part of the texture? Or, is there a better way?
Can't we just correct the texture coordinates / start writing the surface contents at the bottom? Also, if we use EXT_framebuffer_object instead, we probably won't have to use glCopyTexImage in the first place.
