The opensource radeon driver already works very well with Flightgear. Even the shaders do mostly, however there is a problem with the clouds shader. I already posted the problem to the FG forum with some screenshots (see URL above). The relevant shader files can be found here: http://mapserver.flightgear.org/git/gitweb.pl?p=fgdata;a=tree;f=Shaders;hb=HEAD
I also have a problems with cloud with Sandy Bridge (i965 driver), using linux kernel 3.0 or 3.2, Mesa 8.0.1., see [1] in attached picture. I tried with software renderer, still a little line under the clouds sometimes, but far less. Some transparant textures like chimnees on roof ([2] on attached picture) have the transparent part fully black. Only With kernel 3.2 (not with 3.0), that is far faster than 3.0, 2d windows text rendering displays bugs during windowed flightgear ([3] on screenshot), some times texte looks like barcode (vertical Black and white line along the text), some time there is horizontal lines. hiding and redisplaying the window resolve the artifact, but artifact appear again when the view is scrolled. Still during windowed flightgear with Linux-3.2, jpeg display strangly in firefox (4 ?, I can't manage to catch it in screenshot, when I click on gim screenshot window, the problem disappear), pictures looks like randam shift problems on some lines, like on old TV with bad signal reception.
Created attachment 57589 [details] Sandybridge, linux3.2 Mesa 8.0.1 and windowed flightgear bugs.
I just seen that on screenshot, There is the horizontal line on text bug displayed too, at the upperleft part of Stardict window (where there is the 3 frame), on the E of 'Effacer'. Hope this will help to understand the source of the bugs.
For me personally this bug is no longer valid. FG now works very good with latest mesa and radeon driver. As you have quite some other issues, too, I think you might be better off opening another bug. I'll close this one soon.
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