View Full Version : why is GL_COLOR_TABLE so painfully SLOW?

Alex Bourt
05-16-2004, 12:37 AM
For some reason when I glEnable(GL_COLOR_TABLE), the speed of glDrawPixels() goes from lightning fast to turtle slow. With MMX code I can apply brightness, gamma, etc. to my 640x480 image at >100fps, but when I enable the color table the speed drops down to like two seconds per frame. If I disable double buffering I can actually see the pixels being drawn row by row. I did everything like the red book said, the table size is 256, etc. What could be the reason for this?

05-16-2004, 08:00 AM
What is your hardware and driver setup ?

It looks like a fallback to software rendering. The drivers expose the extension for color table, but does it in software.

Alex Bourt
05-16-2004, 12:29 PM
The card is a GeForce FX Go5700 with the driver. This is on a laptop, but seems like the card is new enough to support something as simple as color tables. The laptop is a P4 with 512Mb of RAM if that helps.