Convert HDR scRGB input to normalized linear Rec.2020 before CAS, then
convert the filtered result back to scRGB. Use the content metadata to
select an appropriate normalization peak while leaving SDR unchanged.
This follows AMD's documented recommendation for applying CAS to HDR
content and prevents HDR highlights from being clamped and dimmed.
PQ sources excluded every external filter from the post-process chain.
Decode PQ/BT.2020 into FP16 linear scRGB before active effects and pass
the resulting transfer state to the desktop shader.
Keep the raw PQ path when no effect is active. This avoids adding a
conversion pass or per-frame latency to the common case.
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.
Build the active filter chain only when its configuration changes,
including filter settings or order, input format, dimensions, output
size, and DMA mode.
Unchanged frames now execute only the cached active filters, avoiding
repeated setup, preparation, and output-resolution queries.
Reconfiguration forces a full-frame pass to prevent stale intermediate
framebuffer contents.
Also refresh CAS and FSR uniforms when loading presets and move
downscale pass selection out of the per-frame path.
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 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.
