From 86a09ab03bbdd9d54ebd5730de5392e210d62c13 Mon Sep 17 00:00:00 2001
From: Philippe Renon <philippe_renon@yahoo.fr>
Date: Sat, 9 Jul 2016 16:20:30 +0200
Subject: [PATCH] LP-32 fix build failure with older osg versions

---
 ground/gcs/src/libs/osgearth/osgQtQuick/OSGViewport.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/ground/gcs/src/libs/osgearth/osgQtQuick/OSGViewport.cpp b/ground/gcs/src/libs/osgearth/osgQtQuick/OSGViewport.cpp
index e999def40..458ac0c29 100644
--- a/ground/gcs/src/libs/osgearth/osgQtQuick/OSGViewport.cpp
+++ b/ground/gcs/src/libs/osgearth/osgQtQuick/OSGViewport.cpp
@@ -404,10 +404,12 @@ private:
                 camera->releaseGLObjects(gc->getState());
             }
         }
+#if OSG_VERSION_GREATER_OR_EQUAL(3, 5, 0)
         gc->getState()->releaseGLObjects();
         osg::deleteAllGLObjects(gc->getState()->getContextID());
         osg::flushAllDeletedGLObjects(gc->getState()->getContextID());
         osg::discardAllGLObjects(gc->getState()->getContextID());
+#endif
     }
 
     void createViewer()
@@ -502,7 +504,6 @@ private:
         // if (traits->displayNum < 0) {
         // traits->displayNum = 0;
         // }
-        traits->windowingSystemPreference = "QT";
 
 #if OSG_VERSION_GREATER_OR_EQUAL(3, 5, 3)
         // The MyQt windowing system is registered in osgearth.cpp