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View Full Version : glDisable(GL_LIGHTING) kills framerate



zed
09-26-2000, 10:01 PM
mucking around with me program today, i noticed if i remove the glEnable(GL_LIGHTING) line in the following code me framerate halves like ive hit an software path. ive tried a lot of various combinations for drawing the models immediate,vertex arrays, cva, with/without colours, with/without normals etc ( i know a lot of these combinations are stopid ) does anyone have an ideas

glDisable(GL_LIGHTING)
draw_skybox();
glEnable(GL_LIGHTING);
drawallthemodels();

cheers zed

skw|d
09-26-2000, 11:08 PM
By enabling GL_LIGHTING, you will add vertex lighting calculations for each vertex rendered. Are you sure you don't mean that when you include it you get a performance hit?

/skw|d

zed
09-27-2000, 01:09 AM
no it performs opposite to whats expected (ie faster with lighting and not just a little but twice the speed), BTW im draw q3 models with GL_REPLACE.

Firestorm
09-29-2000, 07:20 AM
Hmm.. doesn't really make sense, i don't seem to have that problem..
What card & driver are you using?
(i have a geforce)

I really suggest you check everything else which could be a factor, like your timing functions..
It could be that you accidentally get wrong timings somehow..

It happened to me before.. i actually tought i had 800fps on a q3a level only to discover that i was doing my timing wrong and i actually had 90fps ;o)
ofcourse i discovered it AFTER telling everyone i had 800fps... ouch..
moral of the story: make sure you're trying to fix the problem not the symptons..