I have an application in which I have to dynamically change the multisampling (ARB_MULTISAMPLE extension). I have this correctly working where I shutdown the window and OpenGL and recreate everything.

The problem I have is that I don’t know exactly what pixel formats and hints map directly to specific multisampling modes. This documentation doesn’t seem to be available anywhere.

I have written nVidia several times about about this but have received no response.

I am using Windows XP with a GeForce FX 6800 Ultra and the latest nVidia drivers.

Any ideas?

The specs for extensions are found at

The GL_ARB_multisample extension is #5 in the list.

That documentation doesn’t give me the information needed to specifically set the correct multisampling mode.

I need a way to query a graphics card for all the available multisampling modes (none, 2x, 2xQ, 4x, 8xS, etc…). Then I need the ability to activate a particular mode.

I read an nVidia document a while ago for the GeForce3 that explained that a combination of hints (GL_FASTEST or GL_NICEST) combined with the number of samples requested is required to set specific multisampling modes. Why is this not documented anywhere?

Also, the lastest nVidia driver only exposes none, 2x, 2xQ, 4x and 8xS as the available multisampling modes on this GeForce FX 6800 Ultra. I believe that there are more available.

Is there any documentation anywhere on this?


If you read the entire spec near the end there are sections for additions to GLX and additions to WGL - these are what you are looking for WGL for Windows, GLX for UNIX/Linux. How the returned values relate directly to 2x, 2xQ, 4x, 8xS I do not know but it is the way to request the info from the driver/card.

You can try to use RivaTuner to enable more FSAA settings. I am getting upto 16x on my 5900 with 66.93 drivers.
I’m not sure if there are any registry tweaks that would allow more FSAA settings in the display control panel.
By the way, ‘latest drivers’ isn’t that accurate, it’s better to specify the version.

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