/*
* Copyright (C) 2021 Christopher J. Howard
*
* This file is part of Antkeeper source code.
*
* Antkeeper source code is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Antkeeper source code is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Antkeeper source code. If not, see .
*/
#ifndef ANTKEEPER_COLOR_XYZ_HPP
#define ANTKEEPER_COLOR_XYZ_HPP
#include "math/math.hpp"
namespace color {
/// Functions which operate in the CIE XYZ colorspace.
namespace xyz {
/**
* Returns the luminance of a CIE XYZ color.
*
* @param x CIE XYZ color.
* @return return Luminance of @p x.
*/
template
T luminance(const math::vector3& x);
/**
* Transforms a CIE XYZ color into the ACEScg colorspace.
*
* @param x CIE XYZ color.
* @return ACEScg color.
*/
template
math::vector3 to_acescg(const math::vector3& x);
/**
* Transforms a CIE XYZ color into the linear sRGB colorspace.
*
* @param x CIE XYZ color.
* @return Linear sRGB color.
*/
template
math::vector3 to_srgb(const math::vector3& x);
/**
* Transforms a CIE XYZ color into the CIE xyY colorspace.
*
* @param x CIE XYZ color.
* @return CIE xyY color.
*/
template
math::vector3 to_xyy(const math::vector3& x);
/// Chromatic Adaptation Transforms (CATs).
namespace cat {
/**
* Transforms a CIE XYZ color with an ACES (~D60) illuminant to a CIE XYZ color with a D65 illuminant using the Bradford chromatic adaption transform.
*
* @param x CIE XYZ color with an ACES (~D60) illuminant.
* @return CIE XYZ color with a D65 illuminant.
*/
template
math::vector3 aces_to_d65(const math::vector3& x);
/**
* Transforms a CIE XYZ color with a D65 illuminant to a CIE XYZ color with an ACES (~D60) illuminant using the Bradford chromatic adaption transform.
*
* @param x CIE XYZ color with a D65 illuminant.
* @return CIE XYZ color with an ACES (~D60) illuminant.
*/
template
math::vector3 d65_to_aces(const math::vector3& x);
} // namespace cat
template
inline T luminance(const math::vector3& x)
{
return x[1];
}
template
math::vector3 to_acescg(const math::vector3& x)
{
static const math::matrix3 xyz_to_acescg
{{
{ 1.641023379694326, -0.663662858722983, 0.011721894328375},
{-0.324803294184790, 1.615331591657338, -0.008284441996237},
{-0.236424695237612, 0.016756347685530, 0.988394858539022}
}};
return xyz_to_acescg * x;
}
template
math::vector3 to_srgb(const math::vector3& x)
{
static const math::matrix3 xyz_to_srgb
{{
{ 3.240969941904523, -0.969243636280880, 0.055630079696994},
{-1.537383177570094, 1.875967501507721, -0.203976958888977},
{-0.498610760293003, 0.041555057407176, 1.056971514242879}
}};
return xyz_to_srgb * x;
}
template
math::vector3 to_xyy(const math::vector3& x)
{
const T sum = x[0] + x[1] + x[2];
return math::vector3
{
x[0] / sum
x[1] / sum,
x[1]
};
}
namespace cat {
template
math::vector3 aces_to_d65(const math::vector3& x)
{
static const math::matrix3 cat_aces_to_d65
{{
{ 0.987225397551079, -0.007603864790602, 0.003066041131217},
{-0.006114800968213, 1.001874800208719, -0.005084242870792},
{ 0.015926393295811, 0.005322023893623, 1.081519155692042}
}};
return cat_aces_to_d65 * x;
}
template
math::vector3 d65_to_aces(const math::vector3& x)
{
static const math::matrix3 cat_d65_to_aces
{{
{ 1.013033366661459, 0.007703617525351, -0.002835673220262},
{ 0.006107049021859, 0.998150224406968, 0.004675010768250},
{-0.014947927269674, -0.005025218608126, 0.924644077051100}
}};
return cat_d65_to_aces * x;
}
} // namespace cat
} // namespace xyz
} // namespace color
#endif // ANTKEEPER_COLOR_XYZ_HPP