From d3cebab9a387842a7fe2431bc07f3d55d2607bbc Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Fri, 21 Oct 2011 10:59:42 +0000
Subject: [PATCH] Added flipDepth() method

---
 include/osg/Image |  6 ++++--
 src/osg/Image.cpp | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/include/osg/Image b/include/osg/Image
index cb099feea..95f9351b7 100644
--- a/include/osg/Image
+++ b/include/osg/Image
@@ -282,12 +282,14 @@ class OSG_EXPORT Image : public BufferData
         Vec4 getColor(const Vec3& texcoord) const;
 
 
-        /** Flip the image horizontally. */
+        /** Flip the image horizontally, around s dimension. */
         void flipHorizontal();
         
-        /** Flip the image vertically. */
+        /** Flip the image vertically, around t dimension. */
         void flipVertical();
 
+        /** Flip the image around the r dimension. Only relevent for 3D textures. */
+        void flipDepth();
 
         /** Ensure image dimensions are a power of two.
           * Mipmapped textures require the image dimensions to be
diff --git a/src/osg/Image.cpp b/src/osg/Image.cpp
index 88f87c7b5..03376e63e 100644
--- a/src/osg/Image.cpp
+++ b/src/osg/Image.cpp
@@ -1181,6 +1181,39 @@ void Image::flipVertical()
     dirty();
 }
 
+void Image::flipDepth()
+{
+    if (_data==NULL)
+    {
+        OSG_WARN << "Error Image::flipVertical() do not succeed : cannot flip NULL image."<<std::endl;
+        return;
+    }
+
+    if (_r==1)
+    {
+        return;
+    }
+
+    if (!_mipmapData.empty() && _r>1)
+    {
+        OSG_WARN << "Error Image::flipVertical() do not succeed : flipping of mipmap 3d textures not yet supported."<<std::endl;
+        return;
+    }
+
+    unsigned int sizeOfSlice = getImageSizeInBytes();
+
+    int r_top = 0;
+    int r_bottom = _r-1;
+    for(; r_top<r_bottom; ++r_top,--r_bottom)
+    {
+        unsigned char* top_slice = data(0,0,r_top);
+        unsigned char* bottom_slice = data(0,0,r_bottom);
+        for(unsigned int i=0; i<sizeOfSlice; ++i, ++top_slice, ++bottom_slice)
+        {
+            std::swap(*top_slice, *bottom_slice);
+        }
+    }
+}
 
 
 void Image::ensureValidSizeForTexturing(GLint maxTextureSize)