Most of the implementation at color state was specific to a color state
generated from parameters so move it to a new class Params.
In the next commits a new color state ICC class will be added.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4144>
clutter_primaries_to_wayland made sense when there only existed
ClutterColorspace. Now that ClutterPrimaries also exist, it makes more
sense to change that func to clutter_colorspace_to_wayland.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4062>
This TF can't be defined as a TransferFunction enum because it needs a
gamma_exp value too.
Add to EOTFType enum a new type: EOTF_TYPE_GAMMA.
With this new type, now EOTFs are unions that can have either
a TransferFunction enum or a gamma_exp.
Set gamma_exp as uniform.
Add the support of it in the color management protocol.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4020>
These properties now are tagged unions:
- ClutterColorimetry:
Can be from colorspace or primaries;
- ClutterEOTF:
Can be from known tf or custom gamma exp (next commit);
- ClutterLuminance:
Can be defined explicitly or derived;
Make the color management protocol use them too.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4020>
ColorState is inmutable so the GObject properties aren't necessary.
Also move ClutterColorstate and ClutterTransferFunction enums to
color-state.h now that they are not used as GObject properties.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4020>
This uses the luminance levels of the color states to anchor the white
of content instead of hard-coding the levels.
This also starts using uniforms for parts of the mapping which means we
don't have to generate and compile a shader when the luminance levels
change.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3953>
They represent the minimum and maximum luminance levels of the primary
color volume and the reference luminance level (reference white, SDR
white, ...) in the reference viewing environment.
They help anchoring the white level, optionally help with preserving the
dynamic range and help with adjusting from a "dark" to a "bright"
viewing environment.
The values have defaults which depend on the transfer characteristics.
This reflects the wayland color management protocol.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3953>
The ID is required for the wayland protocol. In the future we might want
to spend a bit more effort to re-use existing color states when a new
one is requested and also try to re-use IDs instead of just counting up.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3897>
This helper generates shader snippets that converts pixels from one
color state to another. For example if there is content with sRGB color
state that should be converted to linear BT.2020 before being written to
the framebuffer, a shader that makes the pixel go through the following
steps will be generated:
1. sRGB EOTF
2. Luminance gain (hard coded for now)
3. Color space mapping
The intention is that it should be possible to composite in a linear
color space, into an intermediate framebuffer, which is then passed
through an inverse EOTF to produce linear content in the output color
state.
When transforming from BT.2020/PQ to sRGB/sRGB, clamping to the sRGB
max luminance is done.
Cases where direct transform is also handled, i.e. where one doesn't go
via an linear intermediate buffer, in which case there might be both an
EOTF and an inverted EOTF in the same shader snippet to still do color
space mapping using optical color encoding. This will be used for e.g.
transforming cursor sprites.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3433>
ClutterColorState, that is a GObject. each ClutterActor would own
such an object, and it'd be set via a GObject property.
It would have an API to get the colorspace, whether the actor
content is in pq or not, and things like that.
if it is NULL, it will default to color state with sRGB colorspace.
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2443>
