From 36ebf1c5698b5cf2a14056f0b5845c8edc72af75 Mon Sep 17 00:00:00 2001
From: rldhont <rldhont@gmail.com>
Date: Tue, 13 Oct 2015 19:31:57 +0200
Subject: [PATCH] [BUGFIX][QGIS Server] Add layer coordinate transforms before
 setting destination CRS

If the layer_coordinate_transform_info child of mapcanvas has not been well
 saved, the destinationCrs is not well applied and we get a blank image.

To resolve this issue, we just have to add layer coordinate transforms to the
 map renderer before setting the destination CRS.
---
 src/server/qgswmsserver.cpp | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/server/qgswmsserver.cpp b/src/server/qgswmsserver.cpp
index 9e3bf45aa45a..f8c06b6c761d 100644
--- a/src/server/qgswmsserver.cpp
+++ b/src/server/qgswmsserver.cpp
@@ -1899,9 +1899,6 @@ int QgsWMSServer::configureMapRender( const QPaintDevice* paintDevice ) const
       QgsDebugMsg( "Error, could not create output CRS from EPSG" );
       throw QgsMapServiceException( "InvalidCRS", "Could not create output CRS" );
     }
-    mMapRenderer->setDestinationCrs( outputCRS );
-    mMapRenderer->setProjectionsEnabled( true );
-    mapUnits = outputCRS.mapUnits();
 
     //read layer coordinate transforms from project file (e.g. ct with special datum shift)
     if ( mConfigParser )
@@ -1914,6 +1911,11 @@ int QgsWMSServer::configureMapRender( const QPaintDevice* paintDevice ) const
         mMapRenderer->addLayerCoordinateTransform( ltIt->first, t.srcAuthId, t.destAuthId, t.srcDatumTransform, t.destDatumTransform );
       }
     }
+    
+    //then set destinationCrs
+    mMapRenderer->setDestinationCrs( outputCRS );
+    mMapRenderer->setProjectionsEnabled( true );
+    mapUnits = outputCRS.mapUnits();
   }
   mMapRenderer->setMapUnits( mapUnits );