The accumulated time is not the best way to do this as the timer
function callback may not be exactly every 1000ms, by using the
monotonic clock we will get more accurate results.
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.
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.
The renderer may take time to process the cursor update due to various
internal factors, as such it's best we copy the data and mark the
message as done ASAP. This prevents the host from filling up the queue
as easily when a high dpi mouse is in use.
People often miss the warnings about invalid arguments in their command
line, this last minute patch attempts to address this by making
warnings, errors, fixme's and fatal errors stand out if stdout is a TTY.
Conversion from the float values srcW/srcH to the int values for the client window dimensions would sometimes round down, causing the client to scale instead of matching the host's resolution.
A resolution switch could cause the renderer state to become invalid as
the texture format may change while it's being rendered. This fixes this
by adding a lock around the format change and render calls to the
renderer.
Drawing to the front buffer directly requires special handling to
prevent seeing the draw progress (avoiding glClear, etc) and as a result
the output is quite bad unless a compositor is running. Also vsync if
enabled will not function without double buffering enabled.
As OpenGL is the legacy fallback, there are no plans to implement clean
front buffer draw support, so just enable double buffering.
