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.
The existing code would overwrite the texture's data even if the texture
is currently being used to render to screen. This changeset generates a
texture for each buffer preventing this invalid usage.
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.
The $escape+S keybinding now cycles through the available scale algorithms.
This allows the user to switch between algorithms if the automatic detection
turns out to be problematic.
The algorithms are renumbered so that 0 can be LG_SCALE_AUTO.
Reusing cached EGLImages while the frame format has changed will result
in visual artifacts. We should instead destroy the EGLImages and let
them be recreated.
Instead of duplicating the #defines from the shader into the C code,
this commit adds a custom CMake rule that exports all the #defines
from a shader into a C header.
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.
This commit forces the DMA'd memory to be copied into the texture in
the EGL on_frame handler. This avoids tearing when the LG host inevitably
updates the underlying memory. We need an additional copy inside the GPU,
but this is cheap compared to copying from system memory.
We could have used logic to lock the memory buffer, but that would require
performing DMA on every frame, which wastes memory bandwidth. This
manifests as reduced frame rate when moving the mouse compared to the
non-DMA implementation.
We also keep multiple EGLImages, one for each DMA fd, to avoid issues
with the OpenGL driver.
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.
egl_help_set_text and egl_help_render were both accessing bmp->help from
different threads. This creates a race condition in which if the help text
is quickly toggled on and off, it stays on.
This has been fixed with an atomic exchange.
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.
We ask for 32-bit colour buffer when creating the EGL context. On Wayland,
this sometimes give contexts with alpha channels, resulting in unwanted
transparency. So we clear the alpha channel in the desktop shader.
We also switch to using constant alpha for blending the splash, which
avoids more alpha issues.
