From 42953a50bbe5bd7f6318c6a9f6a588a874392094 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marco=20Trevisan=20=28Trevi=C3=B1o=29?= <mail@3v1n0.net>
Date: Thu, 28 Feb 2019 23:02:59 +0100
Subject: [PATCH] stage: Queue redraw previous Rect only if it has changed

No need to queue redraw the same area multiple times, so we can avoid the
computation involved with it.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/3
---
 src/backends/meta-stage.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/backends/meta-stage.c b/src/backends/meta-stage.c
index 425926a7c..1f0d9c050 100644
--- a/src/backends/meta-stage.c
+++ b/src/backends/meta-stage.c
@@ -123,8 +123,11 @@ meta_overlay_paint (MetaOverlay *overlay)
                                    (overlay->current_rect.origin.y +
                                     overlay->current_rect.size.height));
 
-  overlay->previous_rect = overlay->current_rect;
-  overlay->previous_is_valid = TRUE;
+  if (!clutter_rect_equals (&overlay->previous_rect, &overlay->current_rect))
+    {
+      overlay->previous_rect = overlay->current_rect;
+      overlay->previous_is_valid = TRUE;
+    }
 }
 
 static void