Expose High DPI support configuration flag

The High DPI support is enabled by default, so that the renderer use the
full definition of High DPI screens.

However, there are still mouse coordinates problems on some MacOS having
High DPI support (but not all), so expose a way to disable it.

app/meson.build

@@ -80,6 +80,9 @@ conf.set('DEFAULT_BIT_RATE', '8000000')  # 8Mbps
 # SKIP_FRAMES improves latency at the cost of framerate
 conf.set('SKIP_FRAMES', get_option('skip_frames'))
 
+# enable High DPI support
+conf.set('HIDPI_SUPPORT', get_option('hidpi_support'))
+
 configure_file(configuration: conf, output: 'config.h')
 
 executable('scrcpy', src, dependencies: dependencies, install: true)

app/src/screen.c

@@ -140,8 +140,12 @@ SDL_bool screen_init_rendering(struct screen *screen, const char *device_name, s
     screen->frame_size = frame_size;
 
     struct size window_size = get_initial_optimal_size(frame_size);
+    Uint32 window_flags = SDL_WINDOW_HIDDEN | SDL_WINDOW_RESIZABLE;
+#ifdef HIDPI_SUPPORT
+    window_flags |= SDL_WINDOW_ALLOW_HIGHDPI;
+#endif
     screen->window = SDL_CreateWindow(device_name, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED,
-                                      window_size.width, window_size.height, SDL_WINDOW_HIDDEN | SDL_WINDOW_RESIZABLE);
+                                      window_size.width, window_size.height, window_flags);
     if (!screen->window) {
         LOGC("Could not create window: %s", SDL_GetError());
         return SDL_FALSE;

meson_options.txt

@@ -3,3 +3,4 @@ option('build_server', type: 'boolean', value: true, description: 'Build the ser
 option('prebuilt_server', type: 'string', description: 'Path of the prebuilt server')
 option('override_server_path', type: 'string', description: 'Hardcoded path to find the server at runtime')
 option('skip_frames', type: 'boolean', value: true, description: 'Always display the most recent frame')
+option('hidpi_support', type: 'boolean', value: true, description: 'Enable High DPI support')