From 7f1a07487ae0b7039ec38672040fb2674ef57f44 Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Tue, 21 Mar 2017 11:51:34 +1000
Subject: [PATCH] Fix missing initial render of composer maps

---
 src/core/composer/qgscomposermap.cpp | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/core/composer/qgscomposermap.cpp b/src/core/composer/qgscomposermap.cpp
index c3a08100dca..f00100525c0 100644
--- a/src/core/composer/qgscomposermap.cpp
+++ b/src/core/composer/qgscomposermap.cpp
@@ -295,10 +295,8 @@ void QgsComposerMap::paint( QPainter *painter, const QStyleOptionGraphicsItem *,
   }
   else if ( mComposition->plotStyle() == QgsComposition::Preview )
   {
-    //draw cached pixmap. This function does not call cache() any more because
-    //Qt 4.4.0 and 4.4.1 have problems with recursive paintings
-    //QgsComposerMap::cache() and QgsComposerMap::update() need to be called by
-    //client functions
+    if ( mCacheImage.isNull() )
+      cache();
 
     //Background color is already included in cached image, so no need to draw