Copyright © 2023 Joshua Ashton for Valve Software
Copyright © 2023 Xaver Hugl
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The aim of this color management extension is to get HDR games working quickly,
and have an easy way to test implementations in the wild before the upstream
protocol is ready to be merged.
For that purpose it's intentionally limited and cut down and does not serve
all uses cases.
The color management factory singleton creates color managed surface objects.
Interface for changing surface color management and HDR state.
An implementation must: support every part of the version
of the frog_color_managed_surface interface it exposes.
Including all known enums associated with a given version.
Destroying the color managed surface resets all known color
state for the surface back to 'undefined' implementation-specific
values.
Extended information on the transfer functions described
here can be found in the Khronos Data Format specification:
https://registry.khronos.org/DataFormat/specs/1.3/dataformat.1.3.html
Extended information on render intents described
here can be found in ICC.1:2022:
https://www.color.org/specification/ICC.1-2022-05.pdf
NOTE: On a surface with "perceptual" (default) render intent, handling of the container's
color volume
is implementation-specific, and may differ between different transfer functions it is paired
with:
ie. sRGB + 709 rendering may have it's primaries widened to more of the available display's
gamut
to be be more pleasing for the viewer.
Compared to scRGB Linear + 709 being treated faithfully as 709
(including utilizing negatives out of the 709 gamut triangle)
Forwards HDR metadata from the client to the compositor.
HDR Metadata Infoframe as per CTA 861.G spec.
Usage of this HDR metadata is implementation specific and
outside of the scope of this protocol.
Mastering Red Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering Red Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering Green Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering Green Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering Blue Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering Blue Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering White Point X Coordinate of the Data.
These are coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Mastering White Point Y Coordinate of the Data.
These are coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Max Mastering Display Luminance.
This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
Min Mastering Display Luminance.
This value is coded as an unsigned 16-bit value in units of
0.0001 cd/m2, where 0x0001 represents 0.0001 cd/m2 and 0xFFFF
represents 6.5535 cd/m2.
Max Content Light Level.
This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
Max Frame Average Light Level.
This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
Current preferred metadata for a surface.
The application should use this information to tone-map its buffers
to this target before committing.
This metadata does not necessarily correspond to any physical output, but
rather what the compositor thinks would be best for a given surface.
Specifies a known transfer function that corresponds to the
output the surface is targeting.
Output Red Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output Red Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output Green Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output Green Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output Blue Color Primary X Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output Blue Color Primary Y Coordinate of the Data.
Coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output White Point X Coordinate of the Data.
These are coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Output White Point Y Coordinate of the Data.
These are coded as unsigned 16-bit values in units of
0.00002, where 0x0000 represents zero and 0xC350
represents 1.0000.
Max Output Luminance
The max luminance in nits that the output is capable of rendering in small areas.
Content should: not exceed this value to avoid clipping.
This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.
Min Output Luminance
The min luminance that the output is capable of rendering.
Content should: not exceed this value to avoid clipping.
This value is coded as an unsigned 16-bit value in units of
0.0001 cd/m2, where 0x0001 represents 0.0001 cd/m2 and 0xFFFF
represents 6.5535 cd/m2.
Max Full Frame Luminance
The max luminance in nits that the output is capable of rendering for the
full frame sustained.
This value is coded as an unsigned 16-bit value in units of 1 cd/m2,
where 0x0001 represents 1 cd/m2 and 0xFFFF represents 65535 cd/m2.