AGL and multisample AntiAliasing under X

[oxenos]

Hi people, it's me again ;)

I'm trying to do fullscreen antialiasing using multisample. So the question is: is it enough to ask AGL for a multisample buffer with, say, a 4x samples? It seems to work on my radeon video card, but I wonder if this is the general method I should follow with every video card...

thanx in advance for your time!

Paolo

[OneSadCookie]

Do you not have to glEnable(GL_MULTISAMPLE_ARB) or something as well?

Be aware that not all cards may support 4x... it's possible there are some out there that only do 2x, or that in the future some may not support less than 8x...

[oxenos]

Yes, the MULTISAMPLE_ARB should be enabled (strange enough, on my gfx card it works even if I don't enable it explicitly...)

And about 2x, 4x, 8x etc. How can I figure out what are the gfx board capabilities? Should I try all the different configurations until I find one that works (quite weird...)? Or is it some way to ask AGL?

thanx

[OneSadCookie]

Originally posted by oxenos
Yes, the MULTISAMPLE_ARB should be enabled (strange enough, on my gfx card it works even if I don't enable it explicitly...)

I'd consider that a bug. Have you filed a bug report with Apple?

And about 2x, 4x, 8x etc. How can I figure out what are the gfx board capabilities? Should I try all the different configurations until I find one that works (quite weird...)? Or is it some way to ask AGL?

Um, I don't know, but I remember this was discussed on the mac-opengl mailing list when the extension first became available. You can probably find Apple's answer by searching the archives...

[henryj]

I've noticed a few times that multi sample is being reported as enabled even though I haven't explicitly enabled it.

[oxenos]

Ok, so I should enable multisample, and the fact that it's enabled by default should be considered a bug.

thank to all for your time!