Low FPS on OpenGL?

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JunkerKun
Posts: 97
Joined: Mon Jan 28, 2013 12:52 am

Low FPS on OpenGL?

Post by JunkerKun »

I noticed that OpenGL driver is significantly slower than Direct3D one. While D3D9 gives me about 1200 FPS with nothing being drawn, OpenGL gives me 600-650 FPS. What may be the reasons? SFML gives me about the same as D3D9 and it uses OpenGL. I'm confused...
Neirdan
Posts: 39
Joined: Tue Aug 14, 2012 10:29 pm

Re: Low FPS on OpenGL?

Post by Neirdan »

Is your graphic card a GeForce or ATI?
JunkerKun
Posts: 97
Joined: Mon Jan 28, 2013 12:52 am

Re: Low FPS on OpenGL?

Post by JunkerKun »

Neirdan wrote:Is your graphic card a GeForce or ATI?
GeForce
Neirdan
Posts: 39
Joined: Tue Aug 14, 2012 10:29 pm

Re: Low FPS on OpenGL?

Post by Neirdan »

https://developer.nvidia.com/directx

"NVIDIA's GPUs are designed to give the best performance for Direct3D games, and we continue to support the Direct3D development community with GPU drivers, technical papers, and our large set of Direct3D-based examples in our NVIDIA Graphics SDK."

As I thought :)

It will also depends on your shaders, of course.
And generally everything in the graphic pipeline.
OpenGL works best with POT (power of two) textures.
JunkerKun
Posts: 97
Joined: Mon Jan 28, 2013 12:52 am

Re: Low FPS on OpenGL?

Post by JunkerKun »

That still doesn't answer why do I get over 1000 FPS with SFML when both SFML and Irrlicht don't render anything except black screen.
mongoose7
Posts: 1227
Joined: Wed Apr 06, 2011 12:13 pm

Re: Low FPS on OpenGL?

Post by mongoose7 »

Neirdan wrote:https://developer.nvidia.com/directx

"NVIDIA's GPUs are designed to give the best performance for Direct3D games, and we continue to support the Direct3D development community with GPU drivers, technical papers, and our large set of Direct3D-based examples in our NVIDIA Graphics SDK."
I think they mean, better than any other GPU. This probably has nothing to do with OpenGL.

Maybe try rendering a textured cube, to see if there is a performance difference. Rendering nothing doesn't seem to be a good indicator of anything. And 1200 FPS seems very slow - are you using the software renderer :wink:
JunkerKun
Posts: 97
Joined: Mon Jan 28, 2013 12:52 am

Re: Low FPS on OpenGL?

Post by JunkerKun »

mongoose7 wrote:
Neirdan wrote:https://developer.nvidia.com/directx

"NVIDIA's GPUs are designed to give the best performance for Direct3D games, and we continue to support the Direct3D development community with GPU drivers, technical papers, and our large set of Direct3D-based examples in our NVIDIA Graphics SDK."
I think they mean, better than any other GPU. This probably has nothing to do with OpenGL.

Maybe try rendering a textured cube, to see if there is a performance difference. Rendering nothing doesn't seem to be a good indicator of anything.:
When I draw the same scene D3D gives 500 and OpenGL 250.
SFML can't normally render 3D but I used native OpenGL methods to draw it and got about 500 - the same as D3D.
So I'm still confused :V
And 1200 FPS seems very slow - are you using the software rendere
No, I use an old laptop and almost dead OS. I need to at least reinstall the OS.
kklouzal
Posts: 343
Joined: Sun Mar 28, 2010 8:14 pm
Location: USA - Arizona

Re: Low FPS on OpenGL?

Post by kklouzal »

I have an ATI Radeon 8000 HD and my FPS drops 20% when switching from D3D to OGL, this is on all the tutorial applications. The shader one however is even worse.
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hendu
Posts: 2600
Joined: Sat Dec 18, 2010 12:53 pm

Re: Low FPS on OpenGL?

Post by hendu »

That's the fault of your driver provider, who provides worse GL drivers.
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