I am a Mesa/DRI user for few years (Voodoo1, Voodoo3, Radeon 9100, Radeon 9800) and always there were some problems with hardware acceleration of some applications. If I remember correctly there was a problem with wrong texture format or size, usage of some more advanced features and now - just smoothing on r300.

I just read comment for this bug:

https://bugs.freedesktop.org/show_bug.cgi?id=7359

Isn't good solution for Mesa to ask user what is more important - hardware acceleration or some feature?

Maybe it should be configurable with environment variable, for instance - LIBGL_FORCE_SMOOTH_LINE - when set, Mesa will fallback to software rendering if hardware accelerated driver doesn't support smooth lines, when unset - Mesa will just render unsmooth  line or skip it at all (well it may be another variable LIBGL_SKIP_SMOOTH_LINE)

Or is it already possible to configure Mesa this way? Where can I read about it?

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