[gtk/wip/chergert/for-main: 2/9] macos: use display id when creating CVDisplayLink

[Christian Hergert <chergert src gnome org>]

commit 57fca33f70f243ffadd157f43cc309e969504819
Author: Christian Hergert <christian hergert me>
Date:   Fri Feb 25 13:09:31 2022 -0800

    macos: use display id when creating CVDisplayLink
    
    Currently we're using a display link that is for all active displays which
    is just the display server trying to find some timings that try to overlap
    as many as possible.
    
    That was fine for a prototype, but we really need to do better for
    situations with mixed frame rate (such as 60hz and 120hz promotion
    displays). Additionally, the 144hz external monitor I have will never
    reach 144hz using the current design.
    
    This is just the first step in changing this, but the goal is to have
    one of these attached to each GdkMacosMonitor which we can then use to
    thaw surfaces specific to that monitor.

 gdk/macos/gdkdisplaylinksource.c | 15 +++++++--------
 gdk/macos/gdkdisplaylinksource.h | 15 ++++++++-------
 gdk/macos/gdkmacosdisplay.c      |  2 +-
 3 files changed, 16 insertions(+), 16 deletions(-)
---
diff --git a/gdk/macos/gdkdisplaylinksource.c b/gdk/macos/gdkdisplaylinksource.c
index 292b8be519..8b2f1a013f 100644
--- a/gdk/macos/gdkdisplaylinksource.c
+++ b/gdk/macos/gdkdisplaylinksource.c
@@ -147,6 +147,7 @@ gdk_display_link_source_frame_cb (CVDisplayLinkRef   display_link,
 
 /**
  * gdk_display_link_source_new:
+ * @display_id: the identifier of the monitor
  *
  * Creates a new `GSource` that will activate the dispatch function upon
  * notification from a CVDisplayLink that a new frame should be drawn.
@@ -159,7 +160,7 @@ gdk_display_link_source_frame_cb (CVDisplayLinkRef   display_link,
  * Returns: (transfer full): A newly created `GSource`
  */
 GSource *
-gdk_display_link_source_new (void)
+gdk_display_link_source_new (CGDirectDisplayID display_id)
 {
   GdkDisplayLinkSource *impl;
   GSource *source;
@@ -168,15 +169,13 @@ gdk_display_link_source_new (void)
 
   source = g_source_new (&gdk_display_link_source_funcs, sizeof *impl);
   impl = (GdkDisplayLinkSource *)source;
+  impl->display_id = display_id;
 
-  /*
-   * Create our link based on currently connected displays.
-   * If there are multiple displays, this will be something that tries
-   * to work for all of them. In the future, we may want to explore multiple
-   * links based on the connected displays.
+  /* Create DisplayLink for timing information for the display in
+   * question so that we can produce graphics for that display at whatever
+   * rate it can provide.
    */
-  ret = CVDisplayLinkCreateWithActiveCGDisplays (&impl->display_link);
-  if (ret != kCVReturnSuccess)
+  if (CVDisplayLinkCreateWithCGDisplay (display_id, &impl->display_link) != kCVReturnSuccess)
     {
       g_warning ("Failed to initialize CVDisplayLink!");
       return source;
diff --git a/gdk/macos/gdkdisplaylinksource.h b/gdk/macos/gdkdisplaylinksource.h
index ed769b59f8..bff1c91475 100644
--- a/gdk/macos/gdkdisplaylinksource.h
+++ b/gdk/macos/gdkdisplaylinksource.h
@@ -30,17 +30,18 @@ G_BEGIN_DECLS
 
 typedef struct
 {
-  GSource          source;
+  GSource           source;
 
-  CVDisplayLinkRef display_link;
-  gint64           refresh_interval;
-  guint            refresh_rate;
+  CGDirectDisplayID display_id;
+  CVDisplayLinkRef  display_link;
+  gint64            refresh_interval;
+  guint             refresh_rate;
 
-  volatile gint64  presentation_time;
-  volatile guint   needs_dispatch;
+  volatile gint64   presentation_time;
+  volatile guint    needs_dispatch;
 } GdkDisplayLinkSource;
 
-GSource *gdk_display_link_source_new     (void);
+GSource *gdk_display_link_source_new     (CGDirectDisplayID     display_id);
 void     gdk_display_link_source_pause   (GdkDisplayLinkSource *source);
 void     gdk_display_link_source_unpause (GdkDisplayLinkSource *source);
 
diff --git a/gdk/macos/gdkmacosdisplay.c b/gdk/macos/gdkmacosdisplay.c
index ae4c86ad63..6c6771f907 100644
--- a/gdk/macos/gdkmacosdisplay.c
+++ b/gdk/macos/gdkmacosdisplay.c
@@ -273,7 +273,7 @@ gdk_macos_display_frame_cb (gpointer data)
 static void
 gdk_macos_display_load_display_link (GdkMacosDisplay *self)
 {
-  self->frame_source = gdk_display_link_source_new ();
+  self->frame_source = gdk_display_link_source_new (CGMainDisplayID ());
   g_source_set_callback (self->frame_source,
                          gdk_macos_display_frame_cb,
                          self,