Draw a dark square when no texture is rendered

Draw a dark 10x10 square in the top-right corner to distinguish a black frame from the absence of a frame (useful for debugging).
Open the scrcpy window earlier
2026-02-26 08:14:55 +01:00 · 2026-02-26 00:24:40 +01:00 · 2026-02-26 00:24:39 +01:00 · 2026-02-26 00:20:36 +01:00 · 2026-02-26 00:20:17 +01:00
3 changed files with 52 additions and 40 deletions
--- a/app/src/events.h
+++ b/app/src/events.h
@@ -9,6 +9,7 @@

 enum {
    SC_EVENT_NEW_FRAME = SDL_EVENT_USER,
+    SC_EVENT_OPEN_WINDOW,
    SC_EVENT_RUN_ON_MAIN_THREAD,
    SC_EVENT_DEVICE_DISCONNECTED,
    SC_EVENT_SERVER_CONNECTION_FAILED,
--- a/app/src/screen.c
+++ b/app/src/screen.c
@@ -198,19 +198,30 @@ sc_screen_update_content_rect(struct sc_screen *screen) {
 // changed, so that the content rectangle is recomputed
 static void
 sc_screen_render(struct sc_screen *screen, bool update_content_rect) {
-    assert(!screen->video || screen->has_video_window);
+    assert(screen->window_shown);

    if (update_content_rect) {
        sc_screen_update_content_rect(screen);
    }

    SDL_Renderer *renderer = screen->renderer;
+    SDL_SetRenderDrawColor(renderer, 0, 0, 0, 0);
    sc_sdl_render_clear(renderer);

    bool ok = false;
    SDL_Texture *texture = screen->tex.texture;
    if (!texture) {
-        LOGW("No texture to render");
+        // Draw a dark 10x10 square in the top-right corner to distinguish a
+        // black frame from the absence of a frame
+        struct sc_size render_size = sc_sdl_get_render_output_size(renderer);
+        SDL_SetRenderDrawColor(renderer, 0, 0, 0x33, 0xff);
+        SDL_FRect rect = {
+            .x = render_size.width - 20,
+            .y = 10,
+            .w = 10,
+            .h = 10,
+        };
+        SDL_RenderFillRect(renderer, &rect);
        goto end;
    }

@@ -280,11 +291,8 @@ sc_screen_frame_sink_open(struct sc_frame_sink *sink,
                          const AVCodecContext *ctx,
                          const struct sc_stream_session *session) {
    assert(ctx->pix_fmt == AV_PIX_FMT_YUV420P);
-    (void) ctx;
-    (void) session;

    struct sc_screen *screen = DOWNCAST(sink);
-    (void) screen;

    if (ctx->width <= 0 || ctx->width > 0xFFFF
            || ctx->height <= 0 || ctx->height > 0xFFFF) {
@@ -292,6 +300,19 @@ sc_screen_frame_sink_open(struct sc_frame_sink *sink,
        return false;
    }

+    // content_size can be written from this thread, because it is never read
+    // from the main thread before handling SC_EVENT_OPEN_WINDOW (which acts as
+    // a synchronization point) when video is enabled
+    screen->frame_size.width = session->video.width;
+    screen->frame_size.height = session->video.height;
+    screen->content_size = get_oriented_size(screen->frame_size,
+                                             screen->orientation);
+
+    bool ok = sc_push_event(SC_EVENT_OPEN_WINDOW);
+    if (!ok) {
+        return false;
+    }
+
 #ifndef NDEBUG
    screen->open = true;
 #endif
@@ -341,8 +362,7 @@ bool
 sc_screen_init(struct sc_screen *screen,
               const struct sc_screen_params *params) {
    screen->resize_pending = false;
-    screen->has_frame = false;
-    screen->has_video_window = false;
+    screen->window_shown = false;
    screen->paused = false;
    screen->resume_frame = NULL;
    screen->orientation = SC_ORIENTATION_0;
@@ -533,6 +553,7 @@ sc_screen_init(struct sc_screen *screen,

    if (!screen->video) {
        // Show the window immediately
+        screen->window_shown = true;
        sc_sdl_show_window(screen->window);

        if (sc_screen_is_relative_mode(screen)) {
@@ -589,6 +610,7 @@ sc_screen_show_initial_window(struct sc_screen *screen) {
        sc_fps_counter_start(&screen->fps_counter);
    }

+    screen->window_shown = true;
    sc_sdl_show_window(screen->window);
    sc_screen_update_content_rect(screen);
 }
@@ -596,6 +618,7 @@ sc_screen_show_initial_window(struct sc_screen *screen) {
 void
 sc_screen_hide_window(struct sc_screen *screen) {
    sc_sdl_hide_window(screen->window);
+    screen->window_shown = false;
 }

 void
@@ -692,14 +715,14 @@ sc_screen_set_orientation(struct sc_screen *screen,
 static bool
 sc_screen_apply_frame(struct sc_screen *screen) {
    assert(screen->video);
+    assert(screen->window_shown);

    sc_fps_counter_add_rendered_frame(&screen->fps_counter);

    AVFrame *frame = screen->frame;
    struct sc_size new_frame_size = {frame->width, frame->height};

-    if (!screen->has_frame
-            || screen->frame_size.width != new_frame_size.width
+    if (screen->frame_size.width != new_frame_size.width
            || screen->frame_size.height != new_frame_size.height) {

        // frame dimension changed
@@ -707,14 +730,8 @@ sc_screen_apply_frame(struct sc_screen *screen) {

        struct sc_size new_content_size =
            get_oriented_size(new_frame_size, screen->orientation);
-        if (screen->has_frame) {
-            set_content_size(screen, new_content_size);
-            sc_screen_update_content_rect(screen);
-        } else {
-            // This is the first frame
-            screen->has_frame = true;
-            screen->content_size = new_content_size;
-        }
+        set_content_size(screen, new_content_size);
+        sc_screen_update_content_rect(screen);
    }

    bool ok = sc_texture_set_from_frame(&screen->tex, frame);
@@ -722,18 +739,6 @@ sc_screen_apply_frame(struct sc_screen *screen) {
        return false;
    }

-    assert(screen->has_frame);
-    if (!screen->has_video_window) {
-        screen->has_video_window = true;
-        // this is the very first frame, show the window
-        sc_screen_show_initial_window(screen);
-
-        if (sc_screen_is_relative_mode(screen)) {
-            // Capture mouse on start
-            sc_mouse_capture_set_active(&screen->mc, true);
-        }
-    }
-
    sc_screen_render(screen, false);
    return true;
 }
@@ -854,9 +859,17 @@ sc_screen_resize_to_pixel_perfect(struct sc_screen *screen) {

 void
 sc_screen_handle_event(struct sc_screen *screen, const SDL_Event *event) {
-    // !video implies !has_video_window
-    assert(screen->video || !screen->has_video_window);
    switch (event->type) {
+        case SC_EVENT_OPEN_WINDOW:
+            sc_screen_show_initial_window(screen);
+
+            if (sc_screen_is_relative_mode(screen)) {
+                // Capture mouse on start
+                sc_mouse_capture_set_active(&screen->mc, true);
+            }
+
+            sc_screen_render(screen, false);
+            return;
        case SC_EVENT_NEW_FRAME: {
            bool ok = sc_screen_update_frame(screen);
            if (!ok) {
@@ -865,28 +878,27 @@ sc_screen_handle_event(struct sc_screen *screen, const SDL_Event *event) {
            return;
        }
        case SDL_EVENT_WINDOW_EXPOSED:
-            if (!screen->video || screen->has_video_window) {
-                sc_screen_render(screen, true);
-            }
+            sc_screen_render(screen, true);
            return;
        case SDL_EVENT_WINDOW_PIXEL_SIZE_CHANGED:
-            if (screen->has_video_window) {
+            // This event can be triggered before the window is shown
+            if (screen->window_shown) {
                sc_screen_render(screen, true);
            }
            return;
        case SDL_EVENT_WINDOW_RESTORED:
-            if (screen->has_video_window && is_windowed(screen)) {
+            if (screen->video && is_windowed(screen)) {
                apply_pending_resize(screen);
                sc_screen_render(screen, true);
            }
            return;
        case SDL_EVENT_WINDOW_ENTER_FULLSCREEN:
            LOGD("Switched to fullscreen mode");
-            assert(screen->has_video_window);
+            assert(screen->video);
            return;
        case SDL_EVENT_WINDOW_LEAVE_FULLSCREEN:
            LOGD("Switched to windowed mode");
-            assert(screen->has_video_window);
+            assert(screen->video);
            if (is_windowed(screen)) {
                apply_pending_resize(screen);
                sc_screen_render(screen, true);
--- a/app/src/screen.h
+++ b/app/src/screen.h
@@ -70,8 +70,7 @@ struct sc_screen {
    enum sc_orientation orientation;
    // rectangle of the content (excluding black borders)
    struct SDL_FRect rect;
-    bool has_frame;
-    bool has_video_window;
+    bool window_shown;

    AVFrame *frame;
Author	SHA1	Message	Date
Romain Vimont	13039e8db5	Draw a dark square when no texture is rendered Draw a dark 10x10 square in the top-right corner to distinguish a black frame from the absence of a frame (useful for debugging).	2026-02-26 00:24:40 +01:00
Romain Vimont	f2de2c88ff	Open the scrcpy window earlier Previously, the window was opened only once the first frame was available. Instead, open it as soon as the frame dimensions are known. This is especially useful when the encoder does not produce an initial frame while the phone is turned off (e.g., with --no-power-on). Fixes #6546 <https://github.com/Genymobile/scrcpy/issues/6546>	2026-02-26 00:24:39 +01:00
Romain Vimont	2e9175a4ea	Track window shown state Use a flag to indicate whether the window is currently shown. This replaces the old has_video_window flag, which was true only when the window was shown and video was enabled. This will simplify performing actions only when the window is currently shown.	2026-02-26 00:20:36 +01:00
Romain Vimont	e78281c864	Remove unnecessary void cast The ctx variable is used.	2026-02-26 00:20:17 +01:00