Eric Anholt has proposed a new Xorg patch which adds many more combinations of GLXVisuals and XVisuals, to avoid the breakage the above patches could cause to apps wanting a specific feature-set in their GLXVisual to do GL rendering. Lets wait to see what happens upstream on this one.
Quoting the patch's log message:
"""
[PATCH] glx: Replace broken GLX visual setup with a fixed "all" mode.
With trying to match depths so that you didn't end up with a depth 24
fbconfig for the 32-bit composite visual, I broke the alpha bits on the depth
24 X visual, which angered other applications. But in fixing that, the
pickFBconfigs code for "minimal" also could end up breaking GLX visuals if
the same FBconfig was chosen for more than one X visual.
We have no reason to not expose as many visuals as possible, but the old
"all" mode didn't match any existing X visuals to GLX visuals, so normal
GL apps didn't work at all.
Instead, replace it with a simple combination of the two modes: Create GLX
visuals by picking unique FBconfigs with as many features as possible for
each X visual in order. Then, for all remaining FBconfigs that are
appropriate for display, add a corresponding X and GLX visual.
This gets all applications (even ones that aren't smart enough to do FBconfigs)
get all the options to get the visual configuration they want. The only
potential downside is that the composite ARGB visual is unique and gets a
nearly full-featured GLX visual (except that the root visual might have taken
the tastiest FBconfig), which means that a dumb compositing manager could
waste resources. Write compositing managers using FBconfigs instead, please.
"""
UPDATE:
Eric Anholt has proposed a new Xorg patch which adds many more combinations of GLXVisuals and XVisuals, to avoid the breakage the above patches could cause to apps wanting a specific feature-set in their GLXVisual to do GL rendering. Lets wait to see what happens upstream on this one.
Quoting the patch's log message:
"""
[PATCH] glx: Replace broken GLX visual setup with a fixed "all" mode.
With trying to match depths so that you didn't end up with a depth 24
fbconfig for the 32-bit composite visual, I broke the alpha bits on the depth
24 X visual, which angered other applications. But in fixing that, the
pickFBconfigs code for "minimal" also could end up breaking GLX visuals if
the same FBconfig was chosen for more than one X visual.
We have no reason to not expose as many visuals as possible, but the old
"all" mode didn't match any existing X visuals to GLX visuals, so normal
GL apps didn't work at all.
Instead, replace it with a simple combination of the two modes: Create GLX
visuals by picking unique FBconfigs with as many features as possible for
each X visual in order. Then, for all remaining FBconfigs that are
appropriate for display, add a corresponding X and GLX visual.
This gets all applications (even ones that aren't smart enough to do FBconfigs)
get all the options to get the visual configuration they want. The only
potential downside is that the composite ARGB visual is unique and gets a
nearly full-featured GLX visual (except that the root visual might have taken
the tastiest FBconfig), which means that a dumb compositing manager could
waste resources. Write compositing managers using FBconfigs instead, please.
"""