Strange performance issue...

Hello, I’ve noticed a strange performance issue. When my program runs in full screen mode, it runs very slowly and has poor responsiveness. This happens when I use glutFullScreen() or glutInitWindowSize(1024,768), with my monitor resolutions set to 1024x768.

If I set the window size to 1025x769 or 1023x767, the program is nice and fast and snappy. Why does it give me crappy performance only with 1024x768/glutFullScreen()? :confused:


Hi !

What kind of video hardware are you using ?

It might be because you use fullscreen mode, use glGetString in your rendering callback to see if it switches to software rendering in fullscreen mode or something like that.


My video card is an nVidia GeForce FX 5200, I’m running Linux as my OS.

I guess I would want GL_RENDERER, for glGetString()? I’ll try it later today.

I was cleaning up some other code and the bug seems to be fixed: I was loading an OBJ file and I had only intended to load the first texture file referenced in the model file… but it seems I was actually loading a new texture file for every “usemat” in the file… meaning I loaded the same large texture file >50 times! so after I fixed that, the program ran much better in full screen and no longer consumes tonnes of RAM or pages madly… lol!

but I still don’t get why loading that many textures ONLY affected full-screen performance… :confused: