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.
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.
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
This mesh will later be used to render only damaged portions of the desktop.
We also moved the coordinate transformation for damage overlay into a matrix
and computed by the shader.
After the damage queue PR, EGL damage count 0 means no change, and -1 means
invalidate the entire window. However, several other places have different
semantics, and we are not handling them correctly:
1. KVMFR uses 0 to signal invalidating the entire frame, so if we receive 0
rectangles in egl_on_frame, we should set damage count to -1.
2. The damage overlay treated 0 as full damage, which is now incorrect. This
is fixed, and now it treats 0 as no update, and -1 as full damage.
