Add --print-fps to enable FPS counter on start

The FPS counter could be enabled/disabled via MOD+i.

Add a command line option to enable it on start. This is consistent with
other features like --turn-screen-off or --fullscreen.

Fixes #468 <https://github.com/Genymobile/scrcpy/issues/468>
PR #3030 <https://github.com/Genymobile/scrcpy/pull/3030>

app/src/cli.c

@@ -55,6 +55,7 @@
 #define OPT_NO_DOWNSIZE_ON_ERROR   1035
 #define OPT_OTG                    1036
 #define OPT_NO_CLEANUP             1037
+#define OPT_PRINT_FPS              1038
 
 struct sc_option {
     char shortopt;
@@ -336,6 +337,12 @@ static const struct sc_option options[] = {
                 "special character, but breaks the expected behavior of alpha "
                 "keys in games (typically WASD).",
     },
+    {
+        .longopt_id = OPT_PRINT_FPS,
+        .longopt = "print-fps",
+        .text = "Start FPS counter, to print framerate logs to the console. "
+                "It can be started or stopped at any time with MOD+i.",
+    },
     {
         .longopt_id = OPT_PUSH_TARGET,
         .longopt = "push-target",
@@ -1547,6 +1554,9 @@ parse_args_with_getopt(struct scrcpy_cli_args *args, int argc, char *argv[],
             case OPT_NO_CLEANUP:
                 opts->cleanup = false;
                 break;
+            case OPT_PRINT_FPS:
+                opts->start_fps_counter = true;
+                break;
             case OPT_OTG:
 #ifdef HAVE_USB
                 opts->otg = true;

app/src/options.c

@@ -63,4 +63,5 @@ const struct scrcpy_options scrcpy_options_default = {
     .select_tcpip = false,
     .select_usb = false,
     .cleanup = true,
+    .start_fps_counter = false,
 };

app/src/options.h

@@ -138,6 +138,7 @@ struct scrcpy_options {
     bool select_usb;
     bool select_tcpip;
     bool cleanup;
+    bool start_fps_counter;
 };
 
 extern const struct scrcpy_options scrcpy_options_default;

app/src/scrcpy.c

@@ -588,6 +588,7 @@ aoa_hid_end:
             .rotation = options->rotation,
             .mipmaps = options->mipmaps,
             .fullscreen = options->fullscreen,
+            .start_fps_counter = options->start_fps_counter,
             .buffering_time = options->display_buffer,
         };
 

app/src/screen.c

@@ -386,6 +386,7 @@ sc_screen_init(struct sc_screen *screen,
     screen->req.width = params->window_width;
     screen->req.height = params->window_height;
     screen->req.fullscreen = params->fullscreen;
+    screen->req.start_fps_counter = params->start_fps_counter;
 
     static const struct sc_video_buffer_callbacks cbs = {
         .on_new_frame = sc_video_buffer_on_new_frame,
@@ -562,6 +563,10 @@ sc_screen_show_initial_window(struct sc_screen *screen) {
         sc_screen_switch_fullscreen(screen);
     }
 
+    if (screen->req.start_fps_counter) {
+        sc_fps_counter_start(&screen->fps_counter);
+    }
+
     SDL_ShowWindow(screen->window);
 }
 

app/src/screen.h

@@ -35,6 +35,7 @@ struct sc_screen {
         uint16_t width;
         uint16_t height;
         bool fullscreen;
+        bool start_fps_counter;
     } req;
 
     SDL_Window *window;
@@ -93,6 +94,7 @@ struct sc_screen_params {
     bool mipmaps;
 
     bool fullscreen;
+    bool start_fps_counter;
 
     sc_tick buffering_time;
 };