The single-pixel buffer protocol is used to allow wayland clients to
easily draw solid-color rectangles by presenting a 1x1-pixel buffer and
scaling it to the desired size. This patch improves how these buffers
are then handled in the scene-tree renderer.
We already ignore opaque black rectangles at the very bottom (and
anything under them) because we assume we'll be rendering on a black
background. This patch detects black opaque single-pixel buffers and
handles them in the same way as black opaque rectangles. It also
renders single-pixel buffers as rectangles rather than buffers because
this is probably more efficient in the underlying renderer.
In wlr_scene_surface we cache whether the attached buffer is a
single-pixel buffer. This is done because the
wlr_single_pixel_buffer_v1 will be destroyed after texture upload, after
which it becomes much more annoying to check if the buffer is a
single-pixel buffer.
Add wlr_single_pixel_buffer_v1_try_from_buffer() and move `struct
wlr_single_pixel_buffer_v1` to wlr_buffer.h. This allows other code to
find out if a wlr_buffer is a single-pixel buffer and, if so, find out
what color it is.
This avoids processing events which we're not interested in.
Specifically, this fixes a case where output_commit() could be
indirectly called from itself either from import_dmabuf() or while
waiting for a configure event when enabling the output.
Remove unneeded includes of wlr_output.h from wlr_compositor.h and
wlr_cursor.h (unneeded now that we forward-declare struct wlr_surface)
and put the actually-required includes in the right places.
wlr_compositor.h contains references to `struct wlr_surface` in function
arguments before it actually defines it. This generally works because
wlr_compositor.h includes wlr_output.h which contains a
forward-declaration for `struct wlr_surface` (despite not actually
referencing it).
This is all pretty weird, and gives very confusing errors if you manage
to end up with wlr_output.h including wlr_compositor.h (eg. via an
indirect route) so make it less weird.
The old approach of using a signal is fundamentally broken for a common
usecase: When the waiter is ready, it's common to immediately finish and
free any resources associated with it.
Because of the semantics of wl_signal_emit_mutable() this is UB.
wl_signal_emit_mutable() always excepts that the waiter hasn't been freed
until the signal has finished being emitted.
Instead of over engineering the solution, let's just add a callback required
by wlr_drm_syncobj_timeline_waiter_init(). In this callback, the implementation
is free to finish() or free() any resource it likes.
This fixes a problem where an outdated surface input region was used to
compute the effective confinement region.
Additionally, this commit fixes a bug in pointer_constraint_create()
which caused the initial region to not be applied immediately.
This is a breaking change: set_region is now emitted before the role
commit hook is called, and it's not emitted if the region hasn't
actually changed.
