From d7cba048f5982383c78d21008bbe710e04dbbb0e Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Fri, 21 Oct 2011 11:00:29 +0000
Subject: [PATCH] Added support for using negative scale_x, scale_y and scale_z
 values in the <volume> tag to allow presentations to flip the imagery

---
 src/osgPresentation/SlideShowConstructor.cpp | 28 +++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/src/osgPresentation/SlideShowConstructor.cpp b/src/osgPresentation/SlideShowConstructor.cpp
index 62622233b..8cf519fb4 100644
--- a/src/osgPresentation/SlideShowConstructor.cpp
+++ b/src/osgPresentation/SlideShowConstructor.cpp
@@ -1750,10 +1750,12 @@ bool DraggerVolumeTileCallback::receive(const osgManipulator::MotionCommand& com
     }
 }
 
-void SlideShowConstructor::addVolume(const std::string& filename, const PositionData& positionData, const VolumeData& volumeData)
+void SlideShowConstructor::addVolume(const std::string& filename, const PositionData& in_positionData, const VolumeData& volumeData)
 {
     // osg::Object::DataVariance defaultMatrixDataVariance = osg::Object::DYNAMIC; // STATIC
 
+    PositionData positionData(in_positionData);
+
     std::string foundFile = filename;
     osg::ref_ptr<osg::Image> image;
     osg::ref_ptr<osgVolume::Volume> volume;
@@ -1821,6 +1823,30 @@ void SlideShowConstructor::addVolume(const std::string& filename, const Position
     
     if (!image && !volume) return;
 
+    if (positionData.scale.x()<0.0)
+    {
+        image->flipHorizontal();
+        positionData.scale.x() = fabs(positionData.scale.x());
+
+        OSG_INFO<<"addVolume(..) image->flipHorizontal();"<<std::endl;
+    }
+
+    if (positionData.scale.y()<0.0)
+    {
+        image->flipVertical();
+        positionData.scale.y() = fabs(positionData.scale.y());
+
+        OSG_INFO<<"addVolume(..) image->flipVertical();"<<std::endl;
+    }
+
+    if (positionData.scale.z()<0.0)
+    {
+        image->flipDepth();
+        positionData.scale.z() = fabs(positionData.scale.z());
+
+        OSG_INFO<<"addVolume(..) image->flipDepth();"<<std::endl;
+    }
+
     if (volume.valid())
     {
         if (!tile)