Load custom Qt themes from yuzu data directory

- Directory is qt_themes, each theme must be in one folder
    - It should contain a file "style.qss"
    - It may contain an "icons" sub-directory, to override included icons
      (with files like mytheme/icons/colorful/48x48/star.png for example)
    - Directories ending by "_dark" are reserved for dark variant icons.
      They are not listed as themes in the UI.
- If theme directory contains "dark" or "midnight", theme will be considered dark

src/common/fs/fs_paths.h

@@ -15,6 +15,7 @@
 #define CONFIG_DIR "config"
 #define CRASH_DUMPS_DIR "crash_dumps"
 #define DUMP_DIR "dump"
+#define ICONS_DIR "icons"
 #define KEYS_DIR "keys"
 #define LOAD_DIR "load"
 #define LOG_DIR "log"
@@ -24,7 +25,7 @@
 #define SDMC_DIR "sdmc"
 #define SHADER_DIR "shader"
 #define TAS_DIR "tas"
-#define ICONS_DIR "icons"
+#define THEMES_DIR "qt_themes"
 
 // yuzu-specific files
 

src/common/fs/path_util.cpp

@@ -121,6 +121,7 @@ public:
         GenerateYuzuPath(YuzuPath::ConfigDir, yuzu_path_config);
         GenerateYuzuPath(YuzuPath::CrashDumpsDir, yuzu_path / CRASH_DUMPS_DIR);
         GenerateYuzuPath(YuzuPath::DumpDir, yuzu_path / DUMP_DIR);
+        GenerateYuzuPath(YuzuPath::IconsDir, yuzu_path / ICONS_DIR);
         GenerateYuzuPath(YuzuPath::KeysDir, yuzu_path / KEYS_DIR);
         GenerateYuzuPath(YuzuPath::LoadDir, yuzu_path / LOAD_DIR);
         GenerateYuzuPath(YuzuPath::LogDir, yuzu_path / LOG_DIR);
@@ -130,7 +131,7 @@ public:
         GenerateYuzuPath(YuzuPath::SDMCDir, yuzu_path / SDMC_DIR);
         GenerateYuzuPath(YuzuPath::ShaderDir, yuzu_path / SHADER_DIR);
         GenerateYuzuPath(YuzuPath::TASDir, yuzu_path / TAS_DIR);
-        GenerateYuzuPath(YuzuPath::IconsDir, yuzu_path / ICONS_DIR);
+        GenerateYuzuPath(YuzuPath::ThemesDir, yuzu_path / THEMES_DIR);
     }
 
 private:

src/common/fs/path_util.h

@@ -17,6 +17,7 @@ enum class YuzuPath {
     ConfigDir,      // Where config files are stored.
     CrashDumpsDir,  // Where crash dumps are stored.
     DumpDir,        // Where dumped data is stored.
+    IconsDir,       // Where Icons for Windows shortcuts are stored.
     KeysDir,        // Where key files are stored.
     LoadDir,        // Where cheat/mod files are stored.
     LogDir,         // Where log files are stored.
@@ -26,7 +27,7 @@ enum class YuzuPath {
     SDMCDir,        // Where the emulated SDMC is stored.
     ShaderDir,      // Where shaders are stored.
     TASDir,         // Where TAS scripts are stored.
-    IconsDir,       // Where Icons for Windows shortcuts are stored.
+    ThemesDir,      // Where users should put their custom themes
 };
 
 /**