Using the Visual Rating Extension

Using the Visual Rating Extension

To determine the rating for a visual, call glXGetConfig() with attribute set to GLX_VISUAL_CAVEAT_EXT. glXGetConfig() returns the rating of the visual in the parameter value: GLX_NONE_EXT or GLX_SLOW_EXT.

If the GLX_VISUAL_CAVEAT_EXT attribute is not specified in the attrib_list parameter of glXChooseVisual(), preference is given to visuals with no caveats (that is, visuals with the attribute set to GLX_NONE_EXT). If the GLX_VISUAL_CAVEAT_EXT attribute is specified, then glXChooseVisual() matches the specified value exactly. For example, if the value is specified as GLX_NONE_EXT, only visuals with no caveats are considered.