cocoa: option to scale window by HiDPI scale factor

Deactivating this options makes it possible to
circumvent the default OS X behavior of using
points. Windows on HiDPI resolutions won't open
in double the size anymore and videos are display
in their native resolution when windowed.

Fixes #3716

4 files changed, 19 insertions, 2 deletions

diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 6f904b2495..b0fbaf7b93 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -2353,6 +2353,13 @@ Window
         - ``--monitoraspect=4:3``  or ``--monitoraspect=1.3333``
         - ``--monitoraspect=16:9`` or ``--monitoraspect=1.7777``
 
+``--hidpi-window-scale``, ``--no-hidpi-window-scale``
+    (OS X only)
+    Scale the window size according to the backing scale factor (default: yes).
+    On regular HiDPI resolutions the window opens with double the size but appears 
+    as having the same size as on none-HiDPI resolutions. This is the default OS X
+    behavior.
+    
 ``--monitorpixelaspect=<ratio>``
     Set the aspect of a single pixel of your monitor or TV screen (default:
     1). A value of 1 means square pixels (correct for (almost?) all LCDs). See
diff --git a/options/options.c b/options/options.c
index 7a4deae776..e4c682303b 100644
--- a/options/options.c
+++ b/options/options.c
@@ -187,6 +187,7 @@ static const m_option_t mp_vo_opt_list[] = {
     OPT_FLAG("fs-black-out-screens", fs_black_out_screens, 0),
     OPT_FLAG("keepaspect", keepaspect, UPDATE_VIDEOPOS),
     OPT_FLAG("keepaspect-window", keepaspect_window, 0),
+    OPT_FLAG("hidpi-window-scale", hidpi_window_scale, 0),
 #if HAVE_X11
     OPT_CHOICE("x11-netwm", x11_netwm, 0,
                ({"auto", 0}, {"no", -1}, {"yes", 1})),
@@ -216,6 +217,7 @@ const struct m_sub_options vo_sub_opts = {
         .panscan = 0.0f,
         .keepaspect = 1,
         .keepaspect_window = 1,
+        .hidpi_window_scale = 1,
         .taskbar_progress = 1,
         .border = 1,
         .fit_border = 1,
diff --git a/options/options.h b/options/options.h
index 160223d3e1..4ddf9d1490 100644
--- a/options/options.h
+++ b/options/options.h
@@ -38,6 +38,7 @@ typedef struct mp_vo_opts {
 
     int keepaspect;
     int keepaspect_window;
+    int hidpi_window_scale;
 
     int64_t WinID;
 
diff --git a/video/out/cocoa_common.m b/video/out/cocoa_common.m
index ba241f42cc..719169df48 100644
--- a/video/out/cocoa_common.m
+++ b/video/out/cocoa_common.m
@@ -121,9 +121,14 @@ static void run_on_main_thread(struct vo *vo, void(^block)(void))
 static void queue_new_video_size(struct vo *vo, int w, int h)
 {
     struct vo_cocoa_state *s = vo->cocoa;
+    struct mp_vo_opts *opts  = vo->opts;
     if ([s->window conformsToProtocol: @protocol(MpvSizing)]) {
         id<MpvSizing> win = (id<MpvSizing>) s->window;
-        [win queueNewVideoSize:NSMakeSize(w, h)];
+        NSRect r = NSMakeRect(0, 0, w, h);
+        if(!opts->hidpi_window_scale) {
+            r = [s->current_screen convertRectFromBacking:r];
+        }
+        [win queueNewVideoSize:NSMakeSize(r.size.width, r.size.height)];
     }
 }
 
@@ -488,8 +493,10 @@ static void create_ui(struct vo *vo, struct mp_rect *win, int geo_flags)
     if (s->embedded) {
         parent = (NSView *) (intptr_t) opts->WinID;
     } else {
-        const NSRect wr =
+        NSRect wr =
             NSMakeRect(win->x0, win->y0, win->x1 - win->x0, win->y1 - win->y0);
+        if(!opts->hidpi_window_scale)
+            wr = [s->current_screen convertRectFromBacking:wr];
         s->window = create_window(wr, s->current_screen, opts->border, adapter);
         parent = [s->window contentView];
     }