I’m trying to read RGBA data from the frame buffer using glReadPixels. The color data is read fine. However, the alpha doesn’t get read.
The value of GL_ALPHA_BITS is 0 with my setup. The values of GL_RED_BITS, GL_GREEN_BITS, and GL_BLUE_BITS are all 8. Is that the cause of the problem? If so, is there a way to get the frame buffer to have 8 bits of alpha? I’m running on a TNT card, could it be a hardware limitation?
I appreciate any help.