Unity8/Mir not working on VMware due to bypass not working

[Pete Woods]

Related to this bug (bug #1480755) - this is the issue preventing unity8/mir working in VMware.

Bringing it out into its own issue to improve visibility.

Choice quotes from previous bug:

The problem is (annoyingly) that Mesa 10.5.9 on wily (Intel Haswell) returns 7 compatible EGLConfigs for EGL_ALPHA_SIZE=0 but all of them have EGL_ALPHA_SIZE == 8 set.

Added a Mesa task. RAOF has suggested we should just fix Mesa. When asking for RGBA of 8880 it should provide at least one EGLConfig that is 8880 instead of always 8888.

This should be possible. It's not entirely clear why we're not getting XRGB visuals currently, but it's fixable.

[Gerry Boland (gerboland)]

Probably also relevant: https://bugs.launchpad.net/mir/+bug/1560498

[Cemil Azizoglu (cemil-azizoglu)]

FWIW, the new EGL backend for Mir shouldn't suffer from this issue as it respects the config selected by the app. Here's the PPA if someone wants to try [1].

https://launchpad.net/~cemil-azizoglu/+archive/ubuntu/mesa-rs

[1] Note that the new EGL will NOT work with the old (existing) EGL apps yet. You need to port your app (in a trivial way) to use it. Once ported, the old and new EGLs will coexist (i.e. you don't need to port all Mir apps to use the new EGL). Let me know (camako@IRC).

[Daniel van Vugt (vanvugt)]

More recently I had (somewhere) suggested the Mir server interfaces for testing the alpha channel are inadequate. Mir should be able to support the case where an alpha channel exists but is unwanted (similar to glDisable(GL_BLEND)). See also bug 1667577.

That said, bug 1480755 is only a reduction in performance. If Pete is saying that Unity8 doesn't work at all then this would be a duplicate of bug 1560498 (which is actually not what was copied and pasted into the description above from bug 1480755).