[Cogl] [PATCH 0/5] Add a workaround for slow read pixels on Mesa

[Neil Roberts]

The following series of patches add a workaround for the slow
glReadPixels in Mesa on Intel. This is based on the same workaround in
Gnome Shell but Cogl will first try to detect that it is running on an
Intel GPU with Mesa before enabling it because it would probably slow
down other drivers. Mesa >= 8.0.2 already has a fix to make the read
pixels faster so it is also disabled since that version.

The patches try to add a mechanism to make it easier to add driver
specific workarounds in future by having a struct in the context with
some enums to describe the driver.

One of the main advantages of Cogl that we advertise in the blurb is
that it provides a single library to paper over inconsistencies and
bugs in particular drivers so it seems like this is the sort of thing
we should be doing more of in future.