Now that we are drawing with damage rects, when the window is hidden and
then exposed the window may not get fully redrawn. This provides
`app_invalidateWindow` for the display server backend to call when the
screen needs a full redraw.
This is necessary in case overlays change size. When this happens, we must
damage the larger of the overlays' rectangles this frame and last frame.
This erases the overlay from where it is no longer appears.
In order to do this, we must keep track of the rectangles for every overlay
with no exception. We cannot short-circuit the generation of rectangles if
we run out of buffer space, and we must allocate space for MAX_OVERLAY_RECTS
rectangles for every frame. Otherwise, we will not know where to erase the
overlay if it disappears.
While the renderer can internally track this it would be better to
simply provide this information to the renderer directly so it can make
better decisions on how best to update the screen.
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.
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.
Instead of damaging the entire surface when rendering a cursor move,
we can use the EGL_KHR_swap_buffers_with_damage extension to only
damage the part of the window covered by the cursor. This should
reduce the cursor movement latency on Wayland.
We previously used strstr, which can be prone to false positives when
the name of one extension is a substring of another extension.
This commit creates the helper function util_hasGLExt, which asserts
that the substring found in extension list is bounded by either spaces
or the beginning/end of the string.
This commit fixes the issues with the meaning of useNearest being flipped
by removing the variable and use enumerations.
We define an enumeration EGL_DesktopScaleType to express the type of scaling
needed to be performed: no scaling, upscaling, or downscaling. This is
updated when either the frame size or the viewport size changes.
Previously, we only updated the useNearest when the frame size changes.
The desktop shader can now support an enumeration of scaling algorithms,
although only nearest and linear are currently implemented.
Like before, nearest is used when not scaling or upscaling, and linear is
used when downscaling.
Before, if you want to see the FPS, you need to close the client and
restart it with the -k switch to see the FPS. This is annoying.
This PR introduces a new keybind, ScrollLock+D, which, when pressed,
toggles the display of the FPS.
This is implemented for both EGL and OpenGL backends.
This should prevent the looking-glass-client window from having an alpha
channel. On Wayland, the alpha channel is used to compose the window onto
the desktop, so the wallpaper would bleed through unless set to complete
opaque.
We worked around this by using constant alpha for rendering, but it was
not sustainable. Instead, we should just ask for 24-bit context.
This effectively reverts 4bceaf5.
Upstream ticket: https://gitlab.freedesktop.org/mesa/mesa/-/issues/4180
Commit 941c651 makes working around the hang in LG itself not as
annoying as before.
In the future, we can bypass this entire issue by implementing our own
swapchain and listening to frame callbacks ourselves.
