Add flatpak support.

src/main/main.cpp

@@ -608,7 +608,8 @@ int main(int argc, char** argv) {
     reset_audio(48000);
 
     // Source controller mappings file
-    if (SDL_GameControllerAddMappingsFromFile("recompcontrollerdb.txt") < 0) {
+    std::u8string controller_db_path = (zelda64::get_program_path() / "recompcontrollerdb.txt").u8string();
+    if (SDL_GameControllerAddMappingsFromFile(reinterpret_cast<const char *>(controller_db_path.c_str())) < 0) {
         fprintf(stderr, "Failed to load controller mappings: %s\n", SDL_GetError());
     }
 

src/main/support.cpp

@@ -45,13 +45,20 @@ namespace zelda64 {
 
     // MARK: - Public API
 
-    std::filesystem::path get_asset_path(const char* asset) {
-        std::filesystem::path base_path = "";
+    std::filesystem::path get_program_path() {
 #if defined(__APPLE__)
-        base_path = get_bundle_resource_directory();
+        return get_bundle_resource_directory();
+#elif defined(__linux__)
+        std::error_code ec;
+        if (std::filesystem::exists("/.flatpak-info", ec)) {
+            return "/app/bin";
+        }
 #endif
+        return "";
+    }
 
-        return base_path / "assets" / asset;
+    std::filesystem::path get_asset_path(const char* asset) {
+        return get_program_path() / "assets" / asset;
     }
 
     void open_file_dialog(std::function<void(bool success, const std::filesystem::path& path)> callback) {