From f0c63bac7ad16b1ba565a64d631cc344da4f9d0f Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Mon, 20 Jun 2022 22:11:50 +0300
Subject: [PATCH] Support loading sRGB textures

---
 libs/gfx/include/psemek/gfx/pixel.hpp   | 21 +++++++++++++++++++++
 libs/gfx/include/psemek/gfx/texture.hpp | 23 +++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/libs/gfx/include/psemek/gfx/pixel.hpp b/libs/gfx/include/psemek/gfx/pixel.hpp
index fd89d596..07629a79 100644
--- a/libs/gfx/include/psemek/gfx/pixel.hpp
+++ b/libs/gfx/include/psemek/gfx/pixel.hpp
@@ -33,6 +33,9 @@ namespace psemek::gfx
 	template <typename T>
 	struct integer;
 
+	template <typename T>
+	struct srgb;
+
 	template <typename Pixel>
 	struct pixel_traits;
 
@@ -70,6 +73,24 @@ namespace psemek::gfx
 		static constexpr GLenum type = gl::UNSIGNED_BYTE;
 	};
 
+	// Normalized 8-bit sRGB
+
+	template <>
+	struct pixel_traits<srgb<geom::vector<std::uint8_t, 3>>>
+	{
+		static constexpr GLenum internal_format = gl::SRGB8;
+		static constexpr GLenum format = gl::RGB;
+		static constexpr GLenum type = gl::UNSIGNED_BYTE;
+	};
+
+	template <>
+	struct pixel_traits<srgb<geom::vector<std::uint8_t, 4>>>
+	{
+		static constexpr GLenum internal_format = gl::SRGB8_ALPHA8;
+		static constexpr GLenum format = gl::RGBA;
+		static constexpr GLenum type = gl::UNSIGNED_BYTE;
+	};
+
 	// Normalized 10-bit
 
 	template <>
diff --git a/libs/gfx/include/psemek/gfx/texture.hpp b/libs/gfx/include/psemek/gfx/texture.hpp
index 5c56764e..d76e1987 100644
--- a/libs/gfx/include/psemek/gfx/texture.hpp
+++ b/libs/gfx/include/psemek/gfx/texture.hpp
@@ -47,9 +47,15 @@ namespace psemek::gfx
 		template <typename Pixel>
 		void load(geom::vector<std::size_t, D> const & size, Pixel const * data = nullptr);
 
+		template <typename Pixel>
+		void load_srgb(geom::vector<std::size_t, D> const & size, Pixel const * data = nullptr);
+
 		template <typename Pixel>
 		void load(util::array<Pixel, D> const & p);
 
+		template <typename Pixel>
+		void load_srgb(util::array<Pixel, D> const & p);
+
 		void pixels(GLenum format, GLenum type, void * data, int layer = 0) const;
 
 		template <typename Pixmap>
@@ -278,6 +284,14 @@ namespace psemek::gfx
 		load(traits::internal_format, size, traits::format, traits::type, data);
 	}
 
+	template <std::size_t D, GLenum Target>
+	template <typename Pixel>
+	void basic_texture<D, Target>::load_srgb(geom::vector<std::size_t, D> const & size, Pixel const * data)
+	{
+		using traits = pixel_traits<srgb<Pixel>>;
+		load(traits::internal_format, size, traits::format, traits::type, data);
+	}
+
 	template <std::size_t D, GLenum Target>
 	template <typename Pixel>
 	void basic_texture<D, Target>::load(util::array<Pixel, D> const & p)
@@ -287,6 +301,15 @@ namespace psemek::gfx
 		load(size, p.data());
 	}
 
+	template <std::size_t D, GLenum Target>
+	template <typename Pixel>
+	void basic_texture<D, Target>::load_srgb(util::array<Pixel, D> const & p)
+	{
+		geom::vector<std::size_t, D> size;
+		for (std::size_t i = 0; i < D; ++i) size[i] = p.dim(i);
+		load_srgb(size, p.data());
+	}
+
 	template <std::size_t D, GLenum Target>
 	void basic_texture<D, Target>::pixels(GLenum format, GLenum type, void * data, int layer) const
 	{