implement system fonts search for Linux

openVulkanoCpp/Host/Linux/SystemInfo.cpp

@@ -16,6 +16,9 @@
 #include <sys/utsname.h>
 #include <unistd.h>
 #include <thread>
+#include <filesystem>
+#include <functional>
+#include <map>
 
 namespace OpenVulkano
 {
@@ -397,6 +400,34 @@ namespace OpenVulkano
 
 	std::string SystemInfo::GetSystemFontPath(const std::string& fontName)
 	{ 
+		// fontName -> fontPath
+		static std::map<std::string, std::string> fontFilesMapping;
+		if (fontFilesMapping.empty())
+		{
+			const std::filesystem::path fontsDir = "/usr/share/fonts/truetype";
+			std::function<void(const std::filesystem::path)> GetFontFiles;
+			GetFontFiles = [&](const std::filesystem::path& dir)
+			{
+				for (const auto& file : std::filesystem::directory_iterator(dir))
+				{
+					if (file.is_directory())
+					{
+						GetFontFiles(dir / file);
+					}
+					else if (file.path().extension() == ".ttf")
+					{
+						// store font name without extension
+						fontFilesMapping[file.path().stem()] = file.path();
+					}
+				}
+			};
+			GetFontFiles(fontsDir);
+		}
+
+		if (fontFilesMapping.contains(fontName))
+		{
+			return fontFilesMapping.at(fontName);
+		}
 		return "";
 	}
 

tests/CMakeLists.txt

@@ -15,6 +15,17 @@ if (APPLE)
     list(FILTER SOURCES EXCLUDE REGEX "ExeAppendedZipResourceLoader")
 endif()
 
+if (LINUX)
+    find_program(LSB_RELEASE_EXEC lsb_release)
+    execute_process(COMMAND ${LSB_RELEASE_EXEC} -is
+        OUTPUT_VARIABLE LSB_RELEASE_ID_SHORT
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
+    if (NOT ${LSB_RELEASE_ID_SHORT} STREQUAL "Ubuntu")
+        list(FILTER SOURCES EXCLUDE REGEX "*Ubuntu*")
+    endif()
+endif()
+
 source_group(TREE "${CMAKE_CURRENT_SOURCE_DIR}" FILES ${SOURCES})
 file(GLOB_RECURSE RESOURCES "${ROOT_FOLDER}/resources/*.rc" "${ROOT_FOLDER}/resources/*.h")
 list(APPEND SOURCES ${RESOURCES})

tests/Host/Linux/SystemFontsSearchTestsUbuntu.cpp

@@ -0,0 +1,28 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
+
+#include <catch2/catch_all.hpp>
+#include "Base/Logger.hpp"
+#include "Host/SystemInfo.hpp"
+#include "Scene/Text/FontAtlasFactory.hpp"
+#include <filesystem>
+
+using namespace OpenVulkano;
+
+TEST_CASE("Search system fonts")
+{ 
+    Logger::SetupLogger("", "tests.log");
+
+    // assume these fonts are present since they are default
+	std::filesystem::path path = SystemInfo::GetSystemFontPath("Ubuntu-R");
+	REQUIRE(path == "/usr/share/fonts/truetype/ubuntu/Ubuntu-R.ttf");
+
+	path = SystemInfo::GetSystemFontPath("UbuntuMono-BI");
+	REQUIRE(!path.empty());
+
+	path = SystemInfo::GetSystemFontPath("NON-EXISTING Font");
+	REQUIRE(path.empty());
+}

tests/Host/Windows/SystemFontsSearchTests.cpp

@@ -10,7 +10,6 @@
 #include <filesystem>
 
 #include "Scene/Text/FontAtlasFactory.hpp"
-#include "Host/ResourceLoader.hpp"
 
 using namespace OpenVulkano;