From 04cde8059653283097e9b16f2dd72f216b789ff5 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Sat, 25 Jul 2026 03:13:09 +0300
Subject: [PATCH] Add OpenGL support in freetype fonts

---
 libs/fonts/include/psemek/fonts/font_v2.hpp | 18 ++++++---
 libs/fonts/source/freetype.cpp              | 44 +++++++++++++++++++--
 2 files changed, 53 insertions(+), 9 deletions(-)

diff --git a/libs/fonts/include/psemek/fonts/font_v2.hpp b/libs/fonts/include/psemek/fonts/font_v2.hpp
index 53639b11..cf74b4b8 100644
--- a/libs/fonts/include/psemek/fonts/font_v2.hpp
+++ b/libs/fonts/include/psemek/fonts/font_v2.hpp
@@ -5,7 +5,7 @@
 #include <psemek/util/span.hpp>
 
 #if defined(PSEMEK_GRAPHICS_API_OPENGL)
-#error "Fonts v2 don't support OpenGL yet"
+#include <psemek/gfx/texture.hpp>
 #elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 #include <psemek/wgpu/device.hpp>
 #include <psemek/wgpu/texture_view.hpp>
@@ -29,7 +29,7 @@ namespace psemek::fonts
 	};
 
 #if defined(PSEMEK_GRAPHICS_API_OPENGL)
-	// TODO
+	using texture_type = gfx::texture_2d;
 #elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 	using texture_type = wgpu::texture_view;
 #endif
@@ -90,9 +90,17 @@ namespace psemek::fonts
 		virtual ~font_builder() {}
 	};
 
-	std::unique_ptr<font_builder> load_freetype_font(wgpu::device device, std::filesystem::path const & path);
+	struct font_options
+	{
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+		bool nearest_filter = false;
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
+		wgpu::device device;
+#endif
+	};
 
-	// Font paths are specified in order
-	std::unique_ptr<font_builder> load_combined_freetype_font(wgpu::device device, std::vector<std::filesystem::path> const & paths);
+	std::unique_ptr<font_builder> load_freetype_font(font_options const & options, std::filesystem::path const & path);
+	// Font paths are specified in order of priority
+	std::unique_ptr<font_builder> load_combined_freetype_font(font_options const & options, std::vector<std::filesystem::path> const & paths);
 
 }
diff --git a/libs/fonts/source/freetype.cpp b/libs/fonts/source/freetype.cpp
index 4db2eb67..431969f5 100644
--- a/libs/fonts/source/freetype.cpp
+++ b/libs/fonts/source/freetype.cpp
@@ -71,7 +71,11 @@ namespace psemek::fonts
 
 		struct face_shared
 		{
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+			bool nearest_filter;
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 			wgpu::device device;
+#endif
 
 			struct face_data
 			{
@@ -81,6 +85,15 @@ namespace psemek::fonts
 
 			std::vector<face_data> faces = {};
 
+			face_shared(font_options const & options)
+			{
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+				nearest_filter = options.nearest_filter;
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
+				device = options.device;
+#endif
+			}
+
 			~face_shared()
 			{
 				for (auto const & face : faces)
@@ -151,8 +164,13 @@ namespace psemek::fonts
 				int current_row_height = 0;
 				int current_row_x = 0;
 
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+				std::unique_ptr<gfx::texture_2d> texture;
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 				wgpu::texture texture;
 				std::unique_ptr<wgpu::texture_view> texture_view;
+#endif
+
 				bool needs_update = true;
 			};
 
@@ -274,6 +292,15 @@ namespace psemek::fonts
 								pages_.emplace_back();
 								pages_.back().pixmap.resize({page_size, page_size}, 0);
 
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+								pages_.back().texture = std::make_unique<gfx::texture_2d>();
+								pages_.back().texture->load<std::uint8_t>({page_size, page_size});
+								if (state_->nearest_filter)
+									pages_.back().texture->nearest_filter();
+								else
+									pages_.back().texture->linear_filter();
+								pages_.back().texture->clamp();
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 								pages_.back().texture = state_->device.create_texture({
 									.usage = wgpu::texture::usage::copy_dst | wgpu::texture::usage::texture_binding,
 									.dimension = wgpu::texture::dimension::_2d,
@@ -286,6 +313,7 @@ namespace psemek::fonts
 									.dimension = wgpu::texture_view::dimension::_2d,
 									.usage = wgpu::texture::usage::texture_binding,
 								}));
+#endif
 							}
 
 							data->page = pages_.size() - 1;
@@ -312,7 +340,11 @@ namespace psemek::fonts
 					}
 
 					auto & result = shaped_text_.emplace_back();
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+					result.texture = pages_[data->page].texture.get();
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 					result.texture = pages_[data->page].texture_view.get();
+#endif
 					result.position[0].min = pen[0] + data->offset[0];
 					result.position[0].max = result.position[0].min + data->part[0].length();
 					result.position[1].min = pen[1] + data->offset[1];
@@ -332,7 +364,11 @@ namespace psemek::fonts
 						if (!page.needs_update) continue;
 						page.needs_update = false;
 
+#if defined(PSEMEK_GRAPHICS_API_OPENGL)
+						page.texture->load(page.pixmap);
+#elif defined(PSEMEK_GRAPHICS_API_WEBGPU)
 						state_->device.get_queue().write_texture({.texture = page.texture}, {(char *)page.pixmap.data(), page.pixmap.size()}, {.bytes_per_row = page_size, .rows_per_image = page_size}, {page_size, page_size, 1});
+#endif
 					}
 				}
 
@@ -365,14 +401,14 @@ namespace psemek::fonts
 
 	}
 
-	std::unique_ptr<font_builder> load_freetype_font(wgpu::device device, std::filesystem::path const & path)
+	std::unique_ptr<font_builder> load_freetype_font(font_options const & options, std::filesystem::path const & path)
 	{
-		return load_combined_freetype_font(device, {path});
+		return load_combined_freetype_font(options, {path});
 	}
 
-	std::unique_ptr<font_builder> load_combined_freetype_font(wgpu::device device, std::vector<std::filesystem::path> const & paths)
+	std::unique_ptr<font_builder> load_combined_freetype_font(font_options const & options, std::vector<std::filesystem::path> const & paths)
 	{
-		auto result = std::make_shared<face_shared>(device);
+		auto result = std::make_shared<face_shared>(options);
 
 		for (auto const & path : paths)
 		{