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Qu0ll
04-21-2009, 11:56 AM
I have heard reports that antialiasing is a bit of a problem with OpenGL because application settings can be overridden by the graphics card configuration. Is this correct? Is there a way to force antialiasing to be always on? And, are current OpenGL antialiasing techniques as good as traditional CPU-based techniques?

Thanks,

-Qu0ll

dletozeun
04-21-2009, 12:32 PM
As far as I know there is no cross-platform way to enable on the driver side antialiasing through opengl extensions.
The ARB_multisample (http://www.opengl.org/registry/specs/ARB/multisample.txt) extension may interest you to perform antialiasing with multisampling.

Qu0ll
04-21-2009, 02:23 PM
Thanks for the reply. When you say there is no cross-platform way, are you saying that there is a way but it requires platform-specific code? I don't see that as a major problem.

dletozeun
04-21-2009, 03:18 PM
Actually I was thinking of glx or wgl extensions but at first sight I do not see anything about that.

Ilian Dinev
04-21-2009, 04:00 PM
Renders to FBO will always happen in the AA format you want, from my experience.

Qu0ll
04-21-2009, 05:26 PM
Forgive my ignorance but what is FBO?

Ilian Dinev
04-21-2009, 05:56 PM
http://www.gamedev.net/reference/articles/article2331.asp

You can make a FBO be MSAA or CSAA; multisample data needs to be resolved to another FBO via framebuffer-blit.

Generally, antialiasing isn't such a piece of cake as toggling a bool.

Qu0ll
04-21-2009, 06:13 PM
OK, so in layman's terms, if I use an FBO I will be able to control the antialiasing settings from within my application. Correct?

Ilian Dinev
04-21-2009, 09:27 PM
yes

Qu0ll
04-21-2009, 11:02 PM
Thanks.