different improvements

openVulkanoCpp/Host/Windows/SystemFontResolver.cpp

@@ -0,0 +1,66 @@
+/*
+ * 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 "Host/SystemFontResolver.hpp"
+#include <Windows.h>
+#include <filesystem>
+
+#define QFR_DESCRIPTION 1
+
+namespace OpenVulkano
+{
+	std::string SystemFontResolver::GetSystemFontPath(const std::string& fontName)
+	{
+		// font name -> filename
+		static std::map<std::string, std::string> fontFileMapping = ReadSystemFonts();
+		// maybe check everything in lower case ? so that we can use Arial/arial as input parameter
+		auto it = fontFileMapping.find(fontName);
+		return it == fontFileMapping.end() ? "" : it->second;
+	}
+
+	std::map<std::string, std::string> SystemFontResolver::ReadSystemFonts()
+	{
+		std::map<std::string, std::string> fontFileMapping;
+		// thank you Microsoft for function that is not even documented, but exists and it's the only function that
+		// can return real font name from font filename (e.g. font filename is times.ttf that corresponds to Times New Roman)
+		int(WINAPI* GetFontResourceInfoW)(wchar_t*, unsigned long*, void*, unsigned long);
+		*(FARPROC*) &GetFontResourceInfoW = GetProcAddress(GetModuleHandleA("gdi32"), "GetFontResourceInfoW");
+
+		std::wstring winDir;
+		winDir.resize(MAX_PATH);
+		UINT len = GetWindowsDirectoryW(winDir.data(), MAX_PATH);
+		winDir.resize(len);
+		std::filesystem::path fontsDir = std::filesystem::path(winDir) / "Fonts";
+		for (const auto& fontFilename : std::filesystem::directory_iterator(fontsDir))
+		{
+			unsigned long size = 0;
+			std::wstring ws = fontFilename.path().wstring();
+			if (!GetFontResourceInfoW(ws.data(), &size, NULL, QFR_DESCRIPTION))
+			{
+				continue;
+			}
+			std::wstring fontName;
+			fontName.resize(size);
+			if (GetFontResourceInfoW(ws.data(), &size, fontName.data(), QFR_DESCRIPTION))
+			{
+				// remove null-terminated characters since size is always bigger than needed
+				std::string fontNameCropped(fontName.begin(), fontName.end());
+				size_t realSize = 0;
+				for (; realSize < fontNameCropped.size(); realSize++)
+				{
+					if (fontNameCropped[realSize] == '\0')
+					{
+						break;
+					}
+				}
+				fontNameCropped.resize(realSize);
+				fontFileMapping[std::move(fontNameCropped)] = fontFilename.path().string();
+			}
+		}
+		return fontFileMapping;
+	}
+
+}