From 83252397e48561b629bfc9d4c0edd774361b65f3 Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Sat, 12 Jan 2019 03:07:23 +0100
Subject: [PATCH] Ignore WindowManager invalidations inside already invalidated
 rects.

---
 Widgets/Rect.h            | 8 ++++++++
 Widgets/WindowManager.cpp | 9 +++++++--
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/Widgets/Rect.h b/Widgets/Rect.h
index f5e8f773fa..1d613f691e 100644
--- a/Widgets/Rect.h
+++ b/Widgets/Rect.h
@@ -63,6 +63,14 @@ public:
         return contains(point.x(), point.y());
     }
 
+    bool contains(const Rect& other) const
+    {
+        return left() <= other.left()
+            && right() >= other.right()
+            && top() <= other.top()
+            && bottom() >= other.bottom();
+    }
+
     int left() const { return x(); }
     int right() const { return x() + width() - 1; }
     int top() const { return y(); }
diff --git a/Widgets/WindowManager.cpp b/Widgets/WindowManager.cpp
index f371772a45..a3eec92928 100644
--- a/Widgets/WindowManager.cpp
+++ b/Widgets/WindowManager.cpp
@@ -339,8 +339,13 @@ void WindowManager::invalidate()
 
 void WindowManager::invalidate(const Rect& rect)
 {
-    if (!rect.is_empty())
-        m_invalidated_rects.append(rect);
+    if (rect.is_empty())
+        return;
+    for (auto& r : m_invalidated_rects) {
+        if (r.contains(rect))
+            return;
+    }
+    m_invalidated_rects.append(rect);
 }
 
 void WindowManager::invalidate(const Window& window)