FSAA (multisample) on Apple OS X with GLX

squeen wrote on Tuesday, February 28, 2012:

Hi,

I am hoping someone here might be able to help me with an issue I have been
struggling with using GLX/X11 on Apple’s OS X (Snow Leopard). I have an
application that we use on both Linux and Mac that tries to open a glxFBConfig
with multi-sample support (Full Scene Anti-Aliasing). The code works great
on Linux, and even seems to work fine on OS X–both report a context with the
correct number of multi-samples–but on OS X, the scene is still not anti-
aliased.

Would one of the GLFW developers mind telling me is they are able to get FSAA
working (via GLX) on OS X or is it a lost cause?

The other slightly odd OS X wrinkle can be seen directly from a dump of
glxinfo. The first set of configs it lists are label “GLX Visuals” and
none show number multisamples greater than zero. But, in the bottom half of
outputs labeled “GLXFBConfigs” (i.e. the GLX 1.3+ method?) there are a
multiplicity of multisample configs. Programmatically, the result of
glXChooseFBConfig yields configs that each have an associated visual
(GLX_VISUAL_ID). I would expect the two to match like they do under Linux.

The web is oddly silent on this topic. Since GLFW is a cross-platform project
I thought perhaps you folks may have bumped into (and hopefully) solved this
puzzle.

Thanks in advance for any help you may be able to provide.

-squeen

squeen wrote on Wednesday, February 29, 2012:

I received some good news. Apparently OS X 10.7 (Lion) has upgraded the GLX
server version from 1.2 to 1.4 and now supports visuals with multi-sample. The
odd mismatch between glxFBConfigs and visuals was some sort of partial
implementation kludge and FSAA appears to have been straightened out in the
new X11 for OS X.

elmindreda wrote on Wednesday, February 29, 2012:

Thank you for posting the follow-up. It’s good to know that the GLX
implementation of X11.app has been fixed.