ffplay: allow borderless playback windows

For a pure video tile effect, and enabling better integration of playback windows
into other programs. It would improve the looks in many situations and avoid ugly
hacks like this: http://stackoverflow.com/q/31465630/315024

Signed-off-by: Lucas Sandery <lucas-sandery@users.noreply.github.com>
Signed-off-by: Marton Balint <cus@passwd.hu>

doc/ffplay.texi

@@ -62,6 +62,8 @@ see @ref{time duration syntax,,the Time duration section in the ffmpeg-utils(1)
 Seek by bytes.
 @item -nodisp
 Disable graphical display.
+@item -noborder
+Borderless window.
 @item -volume
 Set the startup volume. 0 means silence, 100 means no volume reduction or
 amplification. Negative values are treated as 0, values above 100 are treated

ffplay.c

@@ -321,6 +321,7 @@ static int subtitle_disable;
 static const char* wanted_stream_spec[AVMEDIA_TYPE_NB] = {0};
 static int seek_by_bytes = -1;
 static int display_disable;
+static int borderless;
 static int startup_volume = 100;
 static int show_status = 1;
 static int av_sync_type = AV_SYNC_AUDIO_MASTER;
@@ -1265,6 +1266,8 @@ static int video_open(VideoState *is)
             window_title = input_filename;
         if (is_full_screen)
             flags |= SDL_WINDOW_FULLSCREEN_DESKTOP;
+        if (borderless)
+            flags |= SDL_WINDOW_BORDERLESS;
         window = SDL_CreateWindow(window_title, SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, w, h, flags);
         SDL_SetHint(SDL_HINT_RENDER_SCALE_QUALITY, "linear");
         if (window) {
@@ -3513,6 +3516,7 @@ static const OptionDef options[] = {
     { "t", HAS_ARG, { .func_arg = opt_duration }, "play  \"duration\" seconds of audio/video", "duration" },
     { "bytes", OPT_INT | HAS_ARG, { &seek_by_bytes }, "seek by bytes 0=off 1=on -1=auto", "val" },
     { "nodisp", OPT_BOOL, { &display_disable }, "disable graphical display" },
+    { "noborder", OPT_BOOL, { &borderless }, "borderless window" },
     { "volume", OPT_INT | HAS_ARG, { &startup_volume}, "set startup volume 0=min 100=max", "volume" },
     { "f", HAS_ARG, { .func_arg = opt_format }, "force format", "fmt" },
     { "pix_fmt", HAS_ARG | OPT_EXPERT | OPT_VIDEO, { .func_arg = opt_frame_pix_fmt }, "set pixel format", "format" },