egl/wayland: Ignore rects from SwapBuffersWithDamage
egl/wayland: Ignore rects from SwapBuffersWithDamage

eglSwapBuffersWithDamage accepts damage-region rectangles to hint the
compositor that it only needs to redraw certain areas, which was passed
through the wl_surface_damage request, as designed.

Wayland also offers a buffer transformation interface, e.g. to allow
users to render pre-rotated buffers. Unfortunately, there is no way to
query buffer transforms, and the damage region was provided in surface,
rather than buffer, co-ordinate space.

Users could in theory account for this themselves, but EGL also requires
co-ordinates to be passed in GL/mathematical co-ordinate space, with an
inversion to Wayland's natural/scanout co-ordinate space, so
transformations other than a 180-degree rotation will fail as EGL
attempts to subtract the region from (its view of the) surface height.

Pending creation and acceptance of a wl_surface.buffer_damage request,
which will accept co-ordinates in buffer co-ordinate space, pessimise to
always sending full-surface damage.

bce64c6c provides the explanation for why we send maximum-range damage,
rather than the full size of the surface: in the presence of buffer
transformations, full-surface damage may not actually cover the entire
surface.

Signed-off-by: Daniel Stone <62e7e355d5d8400fa8384448796af0bf6be4ffae@collabora.com>
Reviewed-by: Pekka Paalanen <0f6ae7001e34c37b02fb2c1c2573ddf8f442136a@collabora.co.uk>
Reviewed-by: Jason Ekstrand <b186559eaedf698788888c8a2559b4efb4db10d6@intel.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler