From d4dbc8c8020acd064f0f78c29172ce7abc21ec79 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Gr=C3=A4=C3=9Flin?= <mgraesslin@kde.org>
Date: Fri, 13 Nov 2015 17:12:47 +0100
Subject: [PATCH] Disallow XRender or NoCompositing on Wayland

If the user specifies KWIN_COMPOSE=X or KWIN_COMPOSE=N or config
says Xrender lets fallback to QPainter.
---
 options.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/options.cpp b/options.cpp
index b73e792a14..2d2e82c863 100644
--- a/options.cpp
+++ b/options.cpp
@@ -946,6 +946,10 @@ bool Options::loadCompositingConfig (bool force)
             break;
         }
     }
+    if (kwinApp()->shouldUseWaylandForCompositing() && (compositingMode == XRenderCompositing || compositingMode == NoCompositing)) {
+        qCDebug(KWIN_CORE) << "Compositing forced to QPainter mode by invalid compositor selection";
+        compositingMode = QPainterCompositing;
+    }
     setCompositingMode(compositingMode);
 
     if (m_compositingMode == NoCompositing) {