The implementation of buffer transformation didn't handle transformed
shm buffers properly. The partial texture upload was broken since the
damage is in surface coordinates that don't necessarily match the
buffer's coordinates. It also wouldn't handle the buffer stride
properly, resulting in incorrect rendering if it didn't match the
buffer's width.
The logic used for converting texture coordinates was generalized and
moved out of the renderer, since this conversion may be useful in other
places, such as the backends.
Implement the wl_surface.set_buffer_transform request. This includes
tracking the double-buffered buffer transformation parameter and making
the gl renderer able to handle transformed buffers.
Rename print_egl_error_state() to gl_renderer_print_egl_error_state()
and exports it.
Remove the copy of that function from the rpi backend, and call
the exported function instead.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Move fields current_buffer and buffer_damage out of weston_output into
gl_output_state, since they are actually specific to the renderer.
Also bring back the previous_damage field so that the screenshooter
can get the damage for the previous frame in a renderer independent
way.
