Add BT.709 and BT.2020 color spaces. Improve RGB color space functions.

.gitignore

@@ -5,3 +5,4 @@ bin
 build
 res/data
 .~lock*
+.cache

CMakeLists.txt

@@ -9,6 +9,7 @@ endif()
 cmake_minimum_required(VERSION 3.27)
 include(FetchContent)
 set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 project(Antkeeper
 	VERSION 0.0.1
@@ -354,7 +355,7 @@ target_compile_definitions(${PROJECT_NAME}
 # Set compile options
 target_compile_options(${PROJECT_NAME}
 	PRIVATE
-		$<$<CXX_COMPILER_ID:GNU,Clang>:-Wall -Wextra -pedantic>
+		$<$<CXX_COMPILER_ID:GNU,Clang>:-Wall -Wextra -Wpedantic -Wno-c++98-compat -Wno-c++98-compat-pedantic -Wno-c++11-compat -Wno-c++11-compat-pedantic -Wno-c++14-compat -Wno-c++14-compat-pedantic -Wno-c++17-compat -Wno-c++17-compat-pedantic -Wno-c++20-compat -Wno-c++20-compat-pedantic>
 		$<$<CXX_COMPILER_ID:MSVC>:
 			/W4 /we4265 /we5204 /we5263 /we4946 /we4822 /we4355 /we4061 /we4062 /EHsc /GR-
 			$<$<NOT:$<CONFIG:Debug>>:/GL>

CMakePresets.json

@@ -15,10 +15,17 @@
 			"architecture":
 			{
 				"value": "x64",
-				"strategy": "set"
+				"strategy": "external"
 			},
 			"binaryDir": "${sourceDir}/build/windows-x64"
 		},
+		{
+			"name": "windows-clang-x64",
+			"inherits": "windows-x64",
+			"hidden": true,
+			"toolset": "ClangCL",
+			"binaryDir": "${sourceDir}/build/windows-clang-x64"
+		},
 		{
 			"name": "linux-x64",
 			"hidden": true,
@@ -48,6 +55,24 @@
 				"CMAKE_BUILD_TYPE": "Release"
 			}
 		},
+		{
+			"name": "windows-clang-x64-debug",
+			"displayName": "Windows Clang 64-bit Debug",
+			"inherits": "windows-clang-x64",
+			"cacheVariables":
+			{
+				"CMAKE_BUILD_TYPE": "Debug"
+			}
+		},
+		{
+			"name": "windows-clang-x64-release",
+			"displayName": "Windows Clang 64-bit Release",
+			"inherits": "windows-clang-x64",
+			"cacheVariables":
+			{
+				"CMAKE_BUILD_TYPE": "Release"
+			}
+		},
 		{
 			"name": "linux-x64-debug",
 			"displayName": "Linux 64-bit Debug",
@@ -81,6 +106,18 @@
 			"configurePreset": "windows-x64-release",
 			"configuration": "Release"
 		},
+		{
+			"name": "windows-clang-x64-debug",
+			"displayName": "Windows Clang 64-bit Debug",
+			"configurePreset": "windows-clang-x64-debug",
+			"configuration": "Debug"
+		},
+		{
+			"name": "windows-clang-x64-release",
+			"displayName": "Windows Clang 64-bit Release",
+			"configurePreset": "windows-clang-x64-release",
+			"configuration": "Release"
+		},
 		{
 			"name": "linux-x64-debug",
 			"displayName": "Linux 64-bit Debug",
@@ -94,4 +131,4 @@
 			"configuration": "Release"
 		}
 	]
-}
+}

src/engine/app/sdl/sdl-window-manager.cpp

@@ -84,6 +84,11 @@ sdl_window_manager::sdl_window_manager()
 	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, config::opengl_min_depth_size);
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, config::opengl_min_stencil_size);
 	SDL_GL_SetAttribute(SDL_GL_FRAMEBUFFER_SRGB_CAPABLE, 0);
+
+	// for HDR support
+	// SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 16);
+	// SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 16);
+	// SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 16);
 }
 
 sdl_window_manager::~sdl_window_manager()

src/engine/color/bt2020.hpp

@@ -0,0 +1,115 @@
+// SPDX-FileCopyrightText: 2023 C. J. Howard
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef ANTKEEPER_COLOR_BT2020_HPP
+#define ANTKEEPER_COLOR_BT2020_HPP
+
+#include <engine/color/rgb.hpp>
+#include <cmath>
+
+namespace color {
+
+/// @name ITU-R BT.2020 color space
+/// @{
+
+/// @{
+/**
+ * ITU-R BT.2020 Opto-Electronic Transfer Function (OETF).
+ *
+ * @param x Linear BT.2020 tristimulus.
+ * @param alpha OETF alpha constant.
+ * @param beta OETF beta constant.
+ *
+ * @return Non-linear BT.2020 signal.
+ */
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_oetf(const math::vec3<T>& x, T alpha, T beta)
+{
+	auto f = [alpha, beta](T x) -> T
+	{
+		return x < beta ? T{4.5} * x : alpha * std::pow(x, T{0.45}) - (alpha - T{1});
+	};
+
+	return {f(x[0]), f(x[1]), f(x[2])};
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_oetf_precise(const math::vec3<T>& x)
+{
+	return bt2020_oetf(x, T{1} + T{5.5} * T{0.018053968510807}, T{0.018053968510807});
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_oetf_12_bits(const math::vec3<T>& x)
+{
+	return bt2020_oetf(x, T{1.0993}, T{0.0181});
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_oetf_10_bits(const math::vec3<T>& x)
+{
+	return bt2020_oetf(x, T{1.099}, T{0.018});
+}
+/// @}
+
+/// @{
+/**
+ * ITU-R BT.2020 inverse OETF.
+ *
+ * @param x Non-linear BT.2020 signal.
+ * @param alpha OETF alpha constant.
+ * @param beta OETF beta constant.
+ *
+ * @return Linear BT.2020 tristimulus.
+ */
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_inverse_oetf(const math::vec3<T>& x, T alpha, T beta)
+{
+	const auto oetf_beta = alpha * std::pow(beta, T{0.45}) - (alpha - T{1});
+
+	auto f = [alpha, oetf_beta](T x) -> T
+	{
+		return x < oetf_beta ? x / T{4.5} : std::pow((x + alpha - T{1}) / alpha, T{1} / T{0.45});
+	};
+
+	return {f(x[0]), f(x[1]), f(x[2])};
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_inverse_oetf_precise(const math::vec3<T>& x)
+{
+	return bt2020_inverse_oetf(x, T{1} + T{5.5} * T{0.018053968510807}, T{0.018053968510807});
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_inverse_oetf_12_bits(const math::vec3<T>& x)
+{
+	return bt2020_inverse_oetf(x, T{1.0993}, T{0.0181});
+}
+
+template <class T>
+[[nodiscard]] math::vec3<T> bt2020_inverse_oetf_10_bits(const math::vec3<T>& x)
+{
+	return bt2020_inverse_oetf(x, T{1.099}, T{0.018});
+}
+/// @}
+
+/**
+ * ITU-R BT.2020 color space.
+ */
+template <class T>
+constexpr rgb_color_space<T> bt2020
+(
+	{T{0.7080}, T{0.2920}},
+	{T{0.1700}, T{0.7970}},
+	{T{0.1310}, T{0.0460}},
+	{T{0.3127}, T{0.3290}},
+	&bt2020_oetf_10_bits<T>,
+	&bt2020_inverse_oetf_10_bits<T>
+);
+
+/// @}
+
+} // namespace color
+
+#endif // ANTKEEPER_COLOR_BT2020_HPP

src/engine/color/bt709.hpp

@@ -0,0 +1,71 @@
+// SPDX-FileCopyrightText: 2023 C. J. Howard
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef ANTKEEPER_COLOR_BT709_HPP
+#define ANTKEEPER_COLOR_BT709_HPP
+
+#include <engine/color/rgb.hpp>
+#include <cmath>
+
+namespace color {
+
+/// @name ITU-R BT.709 color space
+/// @{
+
+/**
+ * ITU-R BT.709 Opto-Electronic Transfer Function (OETF).
+ *
+ * @param x Linear BT.709 tristimulus.
+ *
+ * @return Non-linear BT.709 signal.
+ */
+template <class T>
+[[nodiscard]] math::vec3<T> bt709_oetf(const math::vec3<T>& x)
+{
+	auto f = [](T x) -> T
+	{
+		return x < T{0.018} ? T{4.5} * x : T{1.099} * std::pow(x, T{0.45}) - T{0.099};
+	};
+
+	return {f(x[0]), f(x[1]), f(x[2])};
+}
+
+/**
+ * ITU-R BT.709 inverse OETF.
+ *
+ * @param x Non-linear BT.709 signal.
+ *
+ * @return Linear BT.709 tristimulus.
+ */
+template <class T>
+[[nodiscard]] math::vec3<T> bt709_inverse_oetf(const math::vec3<T>& x)
+{
+	const auto oetf_beta = T{1.099} * std::pow(T{0.018}, T{0.45}) - T{0.099};
+
+	auto f = [oetf_beta](T x) -> T
+	{
+		return x < oetf_beta ? x / T{4.5} : std::pow((x + T{0.099}) / T{1.099}, T{1} / T{0.45});
+	};
+
+	return {f(x[0]), f(x[1]), f(x[2])};
+}
+
+/**
+ * ITU-R BT.709 color space.
+ */
+template <class T>
+constexpr rgb_color_space<T> bt709
+(
+	{T{0.6400}, T{0.3300}},
+	{T{0.3000}, T{0.6000}},
+	{T{0.1500}, T{0.0600}},
+	{T{0.3127}, T{0.3290}},
+	&bt709_oetf<T>,
+	&bt709_inverse_oetf<T>
+);
+
+/// @}
+
+} // namespace color
+
+#endif // ANTKEEPER_COLOR_BT709_HPP

src/engine/color/cat.hpp

@@ -63,18 +63,18 @@ template <class T>
 [[nodiscard]] constexpr math::mat3<T> cat_matrix(const math::vec2<T>& w0, const math::vec2<T>& w1, const math::mat3<T>& cone_response = bradford_cone_response<T>) noexcept
 {
 	// Convert CIE xy chromaticity coordinates to CIE XYZ colors
-	const math::vec3<T> w0_xyz = {w0[0] / w0[1], T{1}, (T{1} - w0[0] - w0[1]) / w0[1]};
-	const math::vec3<T> w1_xyz = {w1[0] / w1[1], T{1}, (T{1} - w1[0] - w1[1]) / w1[1]};
+	const math::vec3<T> w0_xyz = {w0.x() / w0.y(), T{1}, (T{1} - w0.x() - w0.y()) / w0.y()};
+	const math::vec3<T> w1_xyz = {w1.x() / w1.y(), T{1}, (T{1} - w1.x() - w1.y()) / w1.y()};
 
 	// Calculate cone response of CIE XYZ colors
-	const math::vec3<T> w0_cone_response = cone_response * w0_xyz;
-	const math::vec3<T> w1_cone_response = cone_response * w1_xyz;
+	const auto cone_response_w0 = cone_response * w0_xyz;
+	const auto cone_response_w1 = cone_response * w1_xyz;
 
 	const math::mat3<T> scale =
 	{
-		w1_cone_response[0] / w0_cone_response[0], T{0}, T{0},
-		T{0}, w1_cone_response[1] / w0_cone_response[1], T{0},
-		T{0}, T{0}, w1_cone_response[2] / w0_cone_response[2],
+		cone_response_w1.x() / cone_response_w0.x(), T{0}, T{0},
+		T{0}, cone_response_w1.y() / cone_response_w0.y(), T{0},
+		T{0}, T{0}, cone_response_w1.z() / cone_response_w0.z(),
 	};
 
 	return math::inverse(cone_response) * scale * cone_response;

src/engine/color/color.hpp

@@ -8,6 +8,8 @@
 namespace color {}
 
 #include <engine/color/aces.hpp>
+#include <engine/color/bt2020.hpp>
+#include <engine/color/bt709.hpp>
 #include <engine/color/cat.hpp>
 #include <engine/color/cct.hpp>
 #include <engine/color/illuminants.hpp>

src/engine/color/illuminants.hpp

@@ -25,13 +25,13 @@ inline constexpr math::vec2<T> deg2_d50  = {T{0.34567}, T{0.35850}};
 template <class T>
 inline constexpr math::vec2<T> deg2_d55  = {T{0.33242}, T{0.34743}};
 template <class T>
-inline constexpr math::vec2<T> deg2_d65  = {T{0.31271}, T{0.32902}};
+inline constexpr math::vec2<T> deg2_d65  = {T{0.31270}, T{0.32900}};
 template <class T>
 inline constexpr math::vec2<T> deg2_d75  = {T{0.29902}, T{0.31485}};
 template <class T>
 inline constexpr math::vec2<T> deg2_d93  = {T{0.28315}, T{0.29711}};
 template <class T>
-inline constexpr math::vec2<T> deg2_e    = {T{0.33333}, T{0.33333}};
+inline constexpr math::vec2<T> deg2_e    = {T{1} / T{3}, T{1} / T{3}};
 template <class T>
 inline constexpr math::vec2<T> deg2_f1   = {T{0.31310}, T{0.33727}};
 template <class T>
@@ -97,7 +97,7 @@ inline constexpr math::vec2<T> deg10_d75 = {T{0.29968}, T{0.31740}};
 template <class T>
 inline constexpr math::vec2<T> deg10_d93 = {T{0.28327}, T{0.30043}};
 template <class T>
-inline constexpr math::vec2<T> deg10_e   = {T{0.33333}, T{0.33333}};
+inline constexpr math::vec2<T> deg10_e   = {T{1} / T{3}, T{1} / T{3}};
 template <class T>
 inline constexpr math::vec2<T> deg10_f1  = {T{0.31811}, T{0.33559}};
 template <class T>