[gimp] macos: reduce frequency of coordinates refresh

[Jehan <jehanp src gnome org>]

commit 6de9ea7022358e1bbad33ba3cb9e4371ebbcb335
Author: Lukas Oberhuber <lukaso gmail com>
Date:   Mon Feb 7 13:44:46 2022 +0000

    macos: reduce frequency of coordinates refresh
    
    This change reduces to 3.33 times a second, the updates to the
    status bar coordinates widget.
    This dramatically improves frame rate on macOS retina displays
    because it reduces the frequency of full screen updates which
    are triggered by this widget updating and are very slow.
    
    This makes the statusbar refresh changes mac only where the
    benefit will be felt keenly, rather than saddling all
    platforms with the change.

 app/display/gimpstatusbar.c | 24 ++++++++++++++++++++++++
 app/display/gimpstatusbar.h | 10 ++++++++++
 2 files changed, 34 insertions(+)
---
diff --git a/app/display/gimpstatusbar.c b/app/display/gimpstatusbar.c
index a7b29a633b..052f58d32d 100644
--- a/app/display/gimpstatusbar.c
+++ b/app/display/gimpstatusbar.c
@@ -1207,8 +1207,32 @@ gimp_statusbar_update_cursor (GimpStatusbar       *statusbar,
   GimpImage        *image;
   gchar             buffer[CURSOR_LEN];
 
+#ifdef GDK_WINDOWING_QUARTZ
+  /*
+   * This optimization dramatically improves drawing refresh speed on Macs with retina
+   * displays, which is all macbook pros since 2016 and macbook airs since 2018 and
+   * running Big Sur (released Nov 2020) or higher.
+   * https://gitlab.gnome.org/GNOME/gimp/-/issues/7690
+   */
+  gint64            curr_time = g_get_monotonic_time ();
+#endif
+
   g_return_if_fail (GIMP_IS_STATUSBAR (statusbar));
 
+#ifdef GDK_WINDOWING_QUARTZ
+  /*
+   * This optimization dramatically improves drawing refresh speed on Macs with retina
+   * displays, which is all macbook pros since 2016 and macbook airs since 2018 and
+   * running Big Sur (released Nov 2020) or higher.
+   * https://gitlab.gnome.org/GNOME/gimp/-/issues/7690
+   */
+  /* only redraw max every 100ms */
+  if (curr_time - statusbar->last_frame_time < 1000 * 300)
+    return;
+
+  statusbar->last_frame_time = curr_time;
+#endif
+
   shell = statusbar->shell;
   image = gimp_display_get_image (shell->display);
 
diff --git a/app/display/gimpstatusbar.h b/app/display/gimpstatusbar.h
index 0caeafb10d..c1d9f78630 100644
--- a/app/display/gimpstatusbar.h
+++ b/app/display/gimpstatusbar.h
@@ -44,6 +44,16 @@ struct _GimpStatusbar
   GHashTable          *context_ids;
   guint                seq_context_id;
 
+#ifdef GDK_WINDOWING_QUARTZ
+  /*
+   * This optimization dramatically improves drawing refresh speed on Macs with retina
+   * displays, which is all macbook pros since 2016 and macbook airs since 2018 and
+   * running Big Sur (released Nov 2020) or higher.
+   * https://gitlab.gnome.org/GNOME/gimp/-/issues/7690
+   */
+  gint64               last_frame_time;
+#endif
+
   GdkPixbuf           *icon;
   GHashTable          *icon_hash;
   gint                 icon_space_width;