CVD correction is composed by a linear transformation, so we should be
able to collapse it into a single matrix multiplication:
Y = M * X
Where Y is the result, X is the original color, and M is the CVD
correction matrix.
As we need to perform CVD correction for every pixel, this can be
beneficial for limited hardware.
In this patch we do that, updating the libweston core code and also the
GL-renderer and its fragment shader.
Suggested-by: Christopher Healy <healych@amazon.com>
Signed-off-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
When repainting a paint node, if the buffer is a solid color buffer we
may skip the rendering pipeline and directly call glClear() with the
solid color, for optimization purposes.
Currently there's a bug where if the output has an output color effect
set, it is skipped when we have a solid color buffer (as we don't go
through the rendering pipeline, where the effects are implemented).
When we have color-management and the paint node contains a color xform,
we've opted for skipping this optimization and going through the
rendering pipeline for now. However, output color effects are simple,
so let's add the logic to apply them on CPU when we have a solid color
buffer.
Reported-by: Christopher Healy <healych@amazon.com>
Signed-off-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
Future development will need to evaluate pipelines with curves and
matrices. Such pipelines naturally operate on vec3, as matrices cannot
be operated one channel at a time. Make weston_color_curve_sample()
operate on arrays of vec3.
Its currently only caller, weston_color_curve_to_3x1D_LUT(), is modified
to employ a temporary array for the API impedance mismatch. This
workaround will be removed later as weston_color_curve_to_3x1D_LUT()
itself will be converted to operate on vec3 arrays.
weston_v3f_array_to_planar() documentation was generated with AI.
weston_color_curve_sample() is restructured a little bit, attempting to
make it simpler to read.
color-operations.h gets the #includes needed to make it self-standing.
Assisted-by: Github Copilot (Claude Sonnet 3.5)
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
Output color effects are applied to the whole output scenegraph. It
depends on color-management being disabled, as the color effects are
applied in sRGB content.
For now we added only a few accessibility options: color inversion,
deuteranopia, protanopia and tritanopia CVD correction.
Note that surfaces presented on outputs that contains a color effect
can't be used for direct scanout (i.e. bypass composition and offloading
to KMS overlay planes). The color effect is applied in our GL-renderer.
Signed-off-by: Leandro Ribeiro <leandro.ribeiro@collabora.com>
This implements the basic color transformation from parametric to
parametric image description. The colorimetric rendering intents are
implemented. The perceptual and saturation rendering intents are
equivalent to media-relative + BPC rendering intent, subject to be
implemented better later.
Things missing:
- handling target color volumes
- perceptual dynamic range mapping
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
This function is required for producing color transformations from
parametric image descriptions.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
3x3 matrices, a straight-forward copy of libalg-4.h.
Useful for color computations and 2-D geometry.
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>
