I need to obtain a color histogram of a synthetic image in the frame buffer. I want compute the histogram in the graphic card, without transferring the frame buffer to the CPU. With glHistogram, I can’t do it without a previous glDrawPixels or a glCopyPixels, which makes impossible run my application in real time.
Is there a solution for this problem for the cards NVIDIA (GeForce 3 or GeForce FX5900) or ATI Radeon 9800 PRO?
Thank you