1. Use atomics and return exact cursor positions from egl_cursor_render
to avoid race conditions between cursor render and update.
2. Instead of messing with lastCursorValid in various overlays, simply use
the hasOverlay/hadOverlay logic for cursor damage. This simplifies the
logic greatly.
As a result, I believe all cursor-related artifacts are fixed.
Note to reviewer: as atomic_init and atomic_store are implemented as macros,
it is currently not possible to pass structs as compound literals due to the
comma being interpreted as an argument separator by the preprocessor.
According to MSDN documentation for CreateEnvironmentBlock, "[i]f the
environment block is passed to CreateProcessAsUser, you must also
specify the CREATE_UNICODE_ENVIRONMENT flag."
Also pass DETACHED_PROCESS because the host is a GUI application and
doesn't use the console.
Since with the service, we are already running as SYSTEM, we don't need
to use dupeSystemProcessToken to get the token for SYSTEM. This removes
the need for having SeDebugPrivilege, SeTcbPrivilege, and
SeAssignPrimaryTokenPrivilege, or otherwise doing sketchy things.
Furthermore, we now only open the token with the privileges we actually
need.
This allows the process to be terminated without resorting to
TerminateProcess. With some fixes, this allows the notification icon to be
removed when the service is restarted.
Furthermore, instead of sending WM_DESTROY to fool the window into believing
it's being destroyed, we actually call DestroyWindow now.
This commit creates a new utility library, eglutil.h, which contains code
to detect and use EGL_KHR_swap_buffers_with_damage or its EXT equivalent.
This logic used to be duplicated between the X11 and Wayland display servers,
which is not ideal.
Instead of using the desktop <GL/gl.h>, we properly use the OpenGL ES 3.x
headers. Also, we now use GL_EXT_buffer_storage for MAP_PERSISTENT_BIT_EXT
and MAP_COHERENT_BIT_EXT as the core versions are only available in desktop
OpenGL 4.4. Similarly, we need GL_EXT_texture_format_BGRA8888 for GL_BGRA_EXT
as GL_BGRA is desktop-only.
This allows us to set a callback to read a value out before it's about
to be overwritten which can be useful for things like calculating a
running average.
For adjacent changed regions, we actually use the bounding box for the
entire polygon. This may result in more area being damaged than strictly
necessary, but is nevertheless desirable since it reduces the number of
rectangles.
