Implement frame resize synchronization on GTK 3

* src/xterm.c (XTframe_up_to_date):
(handle_one_xevent): Use the GTK frame clock to implement frame
resize synchronization.

* src/xterm.h (struct x_output): New variable
`xg_sync_end_pending_p'.

2 files changed, 46 insertions, 2 deletions

diff --git a/src/xterm.c b/src/xterm.c
index 8bdb3c9ea1b..9b480069275 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -1848,10 +1848,14 @@ x_update_end (struct frame *f)
 static void
 XTframe_up_to_date (struct frame *f)
 {
-#ifdef HAVE_XSYNC
+#if defined HAVE_XSYNC && !defined HAVE_GTK3
   XSyncValue add;
   XSyncValue current;
   Bool overflow_p;
+#elif defined HAVE_XSYNC
+  GtkWidget *widget;
+  GdkWindow *window;
+  GdkFrameClock *clock;
 #endif
 
   eassert (FRAME_X_P (f));
@@ -1861,6 +1865,7 @@ XTframe_up_to_date (struct frame *f)
     show_back_buffer (f);
 
 #ifdef HAVE_XSYNC
+#ifndef HAVE_GTK3
   if (FRAME_X_OUTPUT (f)->sync_end_pending_p
       && FRAME_X_BASIC_COUNTER (f) != None)
     {
@@ -1892,6 +1897,20 @@ XTframe_up_to_date (struct frame *f)
 
       FRAME_X_OUTPUT (f)->ext_sync_end_pending_p = false;
     }
+#else
+  if (FRAME_X_OUTPUT (f)->xg_sync_end_pending_p)
+    {
+      widget = FRAME_GTK_OUTER_WIDGET (f);
+      window = gtk_widget_get_window (widget);
+      eassert (window);
+      clock = gdk_window_get_frame_clock (window);
+      eassert (clock);
+
+      gdk_frame_clock_request_phase (clock,
+                                     GDK_FRAME_CLOCK_PHASE_AFTER_PAINT);
+      FRAME_X_OUTPUT (f)->xg_sync_end_pending_p = false;
+    }
+#endif
 #endif
   unblock_input ();
 }
@@ -9130,7 +9149,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                 goto done;
               }
 
-#if defined HAVE_XSYNC && !defined HAVE_GTK3
+#if defined HAVE_XSYNC
             if (event->xclient.data.l[0] == dpyinfo->Xatom_net_wm_sync_request
                 && event->xclient.format == 32
                 && dpyinfo->xsync_supported_p)
@@ -9138,9 +9157,15 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                 struct frame *f
                   = x_top_window_to_frame (dpyinfo,
                                            event->xclient.window);
+#if defined HAVE_GTK3
+                GtkWidget *widget;
+                GdkWindow *window;
+                GdkFrameClock *frame_clock;
+#endif
 
                 if (f)
                   {
+#ifndef HAVE_GTK3
                     if (event->xclient.data.l[4] == 0)
                       {
                         XSyncIntsToValue (&FRAME_X_OUTPUT (f)->pending_basic_counter_value,
@@ -9155,6 +9180,22 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                       }
 
                     *finish = X_EVENT_DROP;
+#else
+                    widget = FRAME_GTK_OUTER_WIDGET (f);
+
+                    if (widget && !FRAME_X_OUTPUT (f)->xg_sync_end_pending_p)
+                      {
+                        window = gtk_widget_get_window (widget);
+                        eassert (window);
+                        frame_clock = gdk_window_get_frame_clock (window);
+                        eassert (frame_clock);
+
+                        gdk_frame_clock_request_phase (frame_clock,
+                                                       GDK_FRAME_CLOCK_PHASE_BEFORE_PAINT);
+
+                        FRAME_X_OUTPUT (f)->xg_sync_end_pending_p = true;
+                      }
+#endif
                     goto done;
                   }
               }
diff --git a/src/xterm.h b/src/xterm.h
index 854d87c83ce..1ce3e7a6cf8 100644
--- a/src/xterm.h
+++ b/src/xterm.h
@@ -822,6 +822,9 @@ struct x_output
 
   bool_bf sync_end_pending_p : 1;
   bool_bf ext_sync_end_pending_p : 1;
+#ifdef HAVE_GTK3
+  bool_bf xg_sync_end_pending_p : 1;
+#endif
 #endif
 
   /* Relief GCs, colors etc.  */