Decode PQ/BT.2020 desktop pixels into an FP16 linear scRGB target before
compositing the color cursor, ImGui, damage overlay, and letterboxing.
Encode the damaged result to PQ once at the surface boundary. Keep logical
AND/XOR cursor masks in the encoded domain.
This preserves premultiplied cursor edges, prevents encoded-domain
blending, uses the Wayland output reference white for local overlays, and
keeps guest cursor white and display calibration independent from frame
SDR white. It also corrects HDR-to-SDR absolute luminance scaling, gamut
matrices, black handling, and buffer-age repair for the extra pass.
Suppress overlays when their conversion framebuffer is unavailable rather
than allowing unconverted sRGB draws into an HDR target.
Use named transfer constants for cursor shader state. Convert clipped
surface rectangles explicitly before using the frame-damage merge helper,
which avoids mixing its unsigned type with the EGL surface rectangle type.
Only advertise native PQ when the FP16 composition target is available.
SDR and native scRGB retain their direct single-pass paths.
Request true floating-point EGL configs for scRGB and expose the native
encodings supported by the selected surface. Fall back to software HDR
mapping when the surface cannot represent the incoming wire format.
Resample PQ in linear light, keep SDR-only effects out of native PQ
chains, and consume the cursor-specific white level without changing
binary monochrome cursor mask operations.
Track context-local GL bindings to avoid redundant program, framebuffer,
buffer, texture, sampler, viewport, blend, and scissor state changes.
Invalidate the cache across context switches, ImGui rendering, and
shared object changes. Preserve CPU-backed texture upload correctness by
explicitly clearing pixel unpack buffer bindings where required.
This reduces hot-path driver overhead without adding waits or GPU
synchronization.
Replace the per-frame uniform list with stable, name-cached handles that
retain their values across shader recompilation. Track dirty uniforms so
only changed values are uploaded, reducing redundant GL calls and buffer
management.
Add a reusable effect-pass pipeline with per-pass shaders, samplers,
formats, resolutions, and intermediate render targets. This makes
external effects easier to integrate and supports arbitrary multipass
chains.
Migrate the desktop, cursor, damage, 24-bit, downscale, CAS, and FSR
rendering paths to the new APIs. Also ensure framebuffer objects are
released correctly.
This patch performs several changes.
* Alters the fourcc codes to types that ignore the alpha channel where
possible to allow the gpu to internally use 24-bit formats.
* Attempts to use DRM_FORMAT_RGB888 first as some GPUs may support this
* If DMABUF is not in use the data is now imported directly as RGB24
without the post-processing shader
According to Erik @ NVidia the open source NVidia driver will not
create a EGLImage from a DMABUF if the target is not
GL_TEXTURE_EXTERNAL_OES. This change set converts the dmabuf texture
from GL_TEXTURE_2D to GL_TEXTURE_EXTERNAL_OES and at runtime performs a
global search & replace on fragment shaders as needed to remain
compatible, replacing `sampler2D` with `samplerExternalOES`.
Ref: https://github.com/NVIDIA/open-gpu-kernel-modules/discussions/243#discussioncomment-3283415
The desktop doesn't need its own sampler, there is already an identically
configured one in the `desktop->texture`.
For some reason, using the texture sampler fixes a black screen issue
with my GTX 660 using the 470.86 driver. Maybe hitting some limit
for how many samplers can be allocated?
NVIDIA still do not implement a complete/working DMABUF implementation
yet advertise support. Best to tell the public to complain to NVIDIA
instead of assuming it's a LG bug or an issue with their system.
This saves a lot of GPU power for partial updates. Running testufo with
lanczos downscaling and FSR upscaling consumed over 90 W, but with this
commit, consumed only 75 W.
