Git commit ee21aba6 removed PanoramiXVisualTable, which was the pre-ABI4 mechanism for drivers & modules to control Xinerama visual consolidation. GLX (and possibly other modules) needs to be able to have a say in which visuals are considered equal in PanoramiXConsolidate.
Created attachment 16349 [details] [review]
I hacked up a patch to fix this. With this, I can get the X server to start in Xinerama with working GLX with the nvidia driver. I didn't convert glxMatchVisual to this interface because I can't test it, but the current hack should work for now.
The global function pointer interface may not be the best way to do this. An alternative would be a function to register a callback, and then the logic for making sure all the stakeholders agree would live in panoramiX.c.
Author: Aaron Plattner <firstname.lastname@example.org>
Date: Sun May 4 13:45:27 2008 -0700
Bug #14692: Allow drivers to have a say in Xinerama visual consolidation.
Create a new exported global variable, XineramaVisualsEqualPtr. Use this
pointer to decide whether two visuals are equal during visual consolidation.
This pointer can be wrapped, which allows drivers and extensions to control
which visuals are consolidated. A wrapper can reject the visuals without
calling down, but must call down and return that result if it deems the visuals
equal. This ensures that all layers agree that the visuals are equal.
Pass the screen of the other visual into the VisualsEqual callchain.
Don't free PanoramiXVisuals since we need it for PanoramiXTranslateVisualID.
Don't skip the first visual on the other screen in PanoramiXMaybeAddVisual.
Skip the loop in PanoramiXTranslateVisualID if screen is 0.
(cherry picked from commit c50b5d978981b13cdb22a9ad41c1b64f90cebe51)