From 02b523f9cda1f5e68dadaf7fc1424cf88737824c Mon Sep 17 00:00:00 2001
From: Andreas Kling <awesomekling@gmail.com>
Date: Thu, 4 Apr 2019 17:35:22 +0200
Subject: [PATCH] WindowServer: Clip dirty cursor rects to the screen in
 compose().

---
 Servers/WindowServer/WSWindowManager.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Servers/WindowServer/WSWindowManager.cpp b/Servers/WindowServer/WSWindowManager.cpp
index d9eb2f7285..3f7fd48df7 100644
--- a/Servers/WindowServer/WSWindowManager.cpp
+++ b/Servers/WindowServer/WSWindowManager.cpp
@@ -874,8 +874,8 @@ void WSWindowManager::process_mouse_event(const WSMouseEvent& event, WSWindow*&
 void WSWindowManager::compose()
 {
     auto dirty_rects = move(m_dirty_rects);
-    dirty_rects.add(m_last_cursor_rect);
-    dirty_rects.add(current_cursor_rect());
+    dirty_rects.add(Rect::intersection(m_last_cursor_rect, m_screen_rect));
+    dirty_rects.add(Rect::intersection(current_cursor_rect(), m_screen_rect));
 #ifdef DEBUG_COUNTERS
     dbgprintf("[WM] compose #%u (%u rects)\n", ++m_compose_count, dirty_rects.rects().size());
 #endif