Properly invalidate XRender surfaces when only EmacsFrame is resized

* src/xterm.c (handle_one_xevent): Drop XRender surfaces when
the frame widget is resized, rather than when the toplevel is.
(bug#77988)

(cherry picked from commit 987cd7012de3cbbdc6a3cfaae337bf9cf752abb3)

diff --git a/src/xterm.c b/src/xterm.c
index 0ff7804112f6c463d46e67f0f9e7cadd2a2f60b9..398669d39a4dd5e1c93d136605f7346151e1a233 100644 (file)
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -21456,45 +21456,49 @@ handle_one_xevent (struct x_display_info *dpyinfo,
        }
 
 #if defined HAVE_GTK3 && defined USE_TOOLKIT_SCROLL_BARS
-         struct scroll_bar *bar = x_window_to_scroll_bar (dpyinfo->display,
-                                                          configureEvent.xconfigure.window, 2);
+      struct scroll_bar *bar = x_window_to_scroll_bar (dpyinfo->display,
+                                                      configureEvent.xconfigure.window, 2);
 
-         /* There is really no other way to make GTK scroll bars fit
-            in the dimensions we want them to.  */
-         if (bar)
+      /* There is really no other way to make GTK scroll bars fit
+        in the dimensions we want them to.  */
+      if (bar)
+       {
+         /* Skip all the pending configure events, not just the
+            ones where window motion occurred.  */
+         while (XPending (dpyinfo->display))
            {
-             /* Skip all the pending configure events, not just the
-                ones where window motion occurred.  */
-             while (XPending (dpyinfo->display))
+             XNextEvent (dpyinfo->display, &next_event);
+             if (next_event.type != ConfigureNotify
+                 || next_event.xconfigure.window != event->xconfigure.window)
                {
-                 XNextEvent (dpyinfo->display, &next_event);
-                 if (next_event.type != ConfigureNotify
-                     || next_event.xconfigure.window != event->xconfigure.window)
-                   {
-                     XPutBackEvent (dpyinfo->display, &next_event);
-                     break;
-                   }
-                 else
-                   configureEvent = next_event;
+                 XPutBackEvent (dpyinfo->display, &next_event);
+                 break;
                }
+             else
+               configureEvent = next_event;
+           }
 
-             if (configureEvent.xconfigure.width != max (bar->width, 1)
-                 || configureEvent.xconfigure.height != max (bar->height, 1))
-               {
-                 XResizeWindow (dpyinfo->display, bar->x_window,
-                                max (bar->width, 1), max (bar->height, 1));
-                 x_flush (WINDOW_XFRAME (XWINDOW (bar->window)));
-               }
+         if (configureEvent.xconfigure.width != max (bar->width, 1)
+             || configureEvent.xconfigure.height != max (bar->height, 1))
+           {
+             XResizeWindow (dpyinfo->display, bar->x_window,
+                            max (bar->width, 1), max (bar->height, 1));
+             x_flush (WINDOW_XFRAME (XWINDOW (bar->window)));
+           }
 
 #ifdef HAVE_XDBE
-             if (f && FRAME_X_DOUBLE_BUFFERED_P (f))
-               x_drop_xrender_surfaces (f);
+         if (f && FRAME_X_DOUBLE_BUFFERED_P (f))
+           x_drop_xrender_surfaces (f);
 #endif
 
-             goto OTHER;
-           }
+         goto OTHER;
+       }
 #endif
 
+      /* XXX: it is strictly only necessary to provide the edit window
+        to many of the statements below which only modify or invalidate
+        resources assigned there.  Most conditionals that alternate
+        between `f' and `any' could ideally be removed.  */
       f = x_top_window_to_frame (dpyinfo, configureEvent.xconfigure.window);
 
       /* This means we can no longer be certain of the root window
@@ -21508,8 +21512,16 @@ handle_one_xevent (struct x_display_info *dpyinfo,
          for size changes: that's not sufficient.  We miss some
          surface invalidations and flicker.  */
 #ifdef HAVE_XDBE
-      if (f && FRAME_X_DOUBLE_BUFFERED_P (f))
-        x_drop_xrender_surfaces (f);
+      {
+#if defined USE_GTK || defined USE_X_TOOLKIT
+       /* Only modifications to the edit window (on which pictures are
+          created) must be accompanied by invalidations.  (bug#77988) */
+       struct frame *f
+         = x_window_to_frame (dpyinfo, configureEvent.xconfigure.window);
+#endif /* USE_GTK || USE_X_TOOLKIT */
+       if (f && FRAME_X_DOUBLE_BUFFERED_P (f))
+         x_drop_xrender_surfaces (f);
+      }
 #endif
 #if defined USE_CAIRO && !defined USE_GTK
       if (f)