reimplement system fonts retrieval for Linux using fontconfig

.vscode/settings.json

@@ -0,0 +1,96 @@
+{
+    "files.associations": {
+        "cctype": "cpp",
+        "clocale": "cpp",
+        "cmath": "cpp",
+        "csetjmp": "cpp",
+        "csignal": "cpp",
+        "cstdarg": "cpp",
+        "cstddef": "cpp",
+        "cstdio": "cpp",
+        "cstdlib": "cpp",
+        "cstring": "cpp",
+        "ctime": "cpp",
+        "cwchar": "cpp",
+        "cwctype": "cpp",
+        "*.ipp": "cpp",
+        "condition_variable": "cpp",
+        "thread": "cpp",
+        "*.inc": "cpp",
+        "any": "cpp",
+        "array": "cpp",
+        "atomic": "cpp",
+        "hash_map": "cpp",
+        "hash_set": "cpp",
+        "strstream": "cpp",
+        "barrier": "cpp",
+        "bit": "cpp",
+        "*.tcc": "cpp",
+        "bitset": "cpp",
+        "cfenv": "cpp",
+        "charconv": "cpp",
+        "chrono": "cpp",
+        "cinttypes": "cpp",
+        "codecvt": "cpp",
+        "compare": "cpp",
+        "complex": "cpp",
+        "concepts": "cpp",
+        "coroutine": "cpp",
+        "cstdint": "cpp",
+        "deque": "cpp",
+        "forward_list": "cpp",
+        "list": "cpp",
+        "map": "cpp",
+        "set": "cpp",
+        "string": "cpp",
+        "unordered_map": "cpp",
+        "unordered_set": "cpp",
+        "vector": "cpp",
+        "exception": "cpp",
+        "algorithm": "cpp",
+        "functional": "cpp",
+        "iterator": "cpp",
+        "memory": "cpp",
+        "memory_resource": "cpp",
+        "numeric": "cpp",
+        "optional": "cpp",
+        "random": "cpp",
+        "ratio": "cpp",
+        "regex": "cpp",
+        "source_location": "cpp",
+        "string_view": "cpp",
+        "system_error": "cpp",
+        "tuple": "cpp",
+        "type_traits": "cpp",
+        "utility": "cpp",
+        "rope": "cpp",
+        "slist": "cpp",
+        "fstream": "cpp",
+        "future": "cpp",
+        "initializer_list": "cpp",
+        "iomanip": "cpp",
+        "iosfwd": "cpp",
+        "iostream": "cpp",
+        "istream": "cpp",
+        "latch": "cpp",
+        "limits": "cpp",
+        "mutex": "cpp",
+        "new": "cpp",
+        "numbers": "cpp",
+        "ostream": "cpp",
+        "ranges": "cpp",
+        "scoped_allocator": "cpp",
+        "semaphore": "cpp",
+        "shared_mutex": "cpp",
+        "span": "cpp",
+        "sstream": "cpp",
+        "stdexcept": "cpp",
+        "stop_token": "cpp",
+        "streambuf": "cpp",
+        "syncstream": "cpp",
+        "typeindex": "cpp",
+        "typeinfo": "cpp",
+        "valarray": "cpp",
+        "variant": "cpp"
+    }
+}

openVulkanoCpp/Host/Linux/SystemFontResolver.cpp

@@ -5,17 +5,56 @@
  */
 
 #include "Host/SystemFontResolver.hpp"
-#include <filesystem>
+#include "Base/Logger.hpp"
+#include <fontconfig/fontconfig.h>
 
 namespace OpenVulkano
 {
 	std::string SystemFontResolver::GetSystemFontPath(const std::string& fontName)
 	{
+		// fontName -> fontPath
+		static std::map<std::string, std::string> fontFilesMapping = ReadSystemFonts();
+		auto it = fontFilesMapping.find(fontName);
+		if (it != fontFilesMapping.end())
+		{
+			return it->second;
+		}
 		return "";
 	}
 
 	std::map<std::string, std::string> SystemFontResolver::ReadSystemFonts()
 	{
+		FcConfig* config = FcInitLoadConfigAndFonts();
+		FcPattern* pat = FcPatternCreate();
+		FcObjectSet* os = FcObjectSetBuild(FC_FAMILY, FC_STYLE, FC_LANG, FC_FILE, NULL);
+		FcFontSet* fs = FcFontList(config, pat, os);
+		if (!fs)
+		{
+			Logger::DATA->warn("Could not get system fonts");
+			FcFontSetDestroy(fs);
+			FcObjectSetDestroy(os);
+			FcPatternDestroy(pat);
 			return {};
 		}
+
+		std::map<std::string, std::string> fontFilesMapping;
+		for (int i = 0; i < fs->nfont; ++i)
+		{
+			FcPattern* font = fs->fonts[i];
+			FcChar8* file, *style, *family;
+			if (FcPatternGetString(font, FC_FILE, 0, &file) == FcResultMatch &&
+				FcPatternGetString(font, FC_FAMILY, 0, &family) == FcResultMatch &&
+				FcPatternGetString(font, FC_STYLE, 0, &style) == FcResultMatch)
+			{
+				fontFilesMapping[std::string(reinterpret_cast<char*>(family)) + " " +
+								 std::string(reinterpret_cast<char*>(style))]
+								 = std::string(reinterpret_cast<char*>(file));
+			}
+		}
+		FcFontSetDestroy(fs);
+		FcObjectSetDestroy(os);
+		FcPatternDestroy(pat);
+		FcConfigDestroy(config);
+		return fontFilesMapping;
+	}
 }

tests/Host/Linux/SystemFontsSearchTestsUbuntu.cpp

@@ -5,9 +5,8 @@
  */
 
 #include <catch2/catch_all.hpp>
+#include "Host/SystemFontResolver.hpp"
 #include "Base/Logger.hpp"
-#include "Host/SystemInfo.hpp"
-#include "Scene/Text/FontAtlasFactory.hpp"
 #include <filesystem>
 
 using namespace OpenVulkano;
@@ -17,12 +16,12 @@ 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");
+	std::string path = SystemFontResolver::GetSystemFontPath("Ubuntu Regular");
 	REQUIRE(path == "/usr/share/fonts/truetype/ubuntu/Ubuntu-R.ttf");
 
-	path = SystemInfo::GetSystemFontPath("UbuntuMono-BI");
+	path = SystemFontResolver::GetSystemFontPath("Ubuntu Mono Bold Italic");
-	REQUIRE(!path.empty());
+	REQUIRE(path == "/usr/share/fonts/truetype/ubuntu/UbuntuMono-BI.ttf");
 
-	path = SystemInfo::GetSystemFontPath("NON-EXISTING Font");
+	path = SystemFontResolver::GetSystemFontPath("NON-EXISTING Font");
 	REQUIRE(path.empty());
 }