Cleaned up osgTerrain, renaming the Terrain and Renderer class to

HeightFieldNode and HeightFieldRender to better reflect their function.
Removed the GeoMipMapRenderer.cpp stub as the implemention will be left
to a plugin.  Added Version functions.

src/osgTerrain/HeightFieldNode.cpp

@@ -0,0 +1,108 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield 
+ *
+ * This library is open source and may be redistributed and/or modified under  
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or 
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * OpenSceneGraph Public License for more details.
+*/
+
+#include <osgTerrain/HeightFieldNode>
+
+using namespace osgTerrain;
+
+HeightFieldNode::HeightFieldNode()
+{
+    setNumChildrenRequiringUpdateTraversal(1);
+}
+
+HeightFieldNode::HeightFieldNode(const HeightFieldNode& terrain,const osg::CopyOp& copyop):
+    Group(terrain,copyop),
+    _heightField(terrain._heightField)
+{
+    setNumChildrenRequiringUpdateTraversal(getNumChildrenRequiringUpdateTraversal()+1);
+    if (terrain.getRenderer()) setRenderer(dynamic_cast<HeightFieldRenderer*>(terrain.getRenderer()->cloneType()));
+}
+
+HeightFieldNode::~HeightFieldNode()
+{
+}
+
+void HeightFieldNode::traverse(osg::NodeVisitor& nv)
+{
+    // if app traversal update the frame count.
+    if (nv.getVisitorType()==osg::NodeVisitor::UPDATE_VISITOR)
+    {
+        osgUtil::UpdateVisitor* uv = dynamic_cast<osgUtil::UpdateVisitor*>(&nv);
+        if (getRenderer() && uv)
+        {
+            getRenderer()->update(uv);
+            return;
+        }        
+        
+    }
+    else if (nv.getVisitorType()==osg::NodeVisitor::CULL_VISITOR)
+    {
+        osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(&nv);
+        if (getRenderer() && cv)
+        {
+            getRenderer()->cull(cv);
+            return;
+        }
+    }
+
+    // otherwise fallback to the Group::traverse()
+    osg::Group::traverse(nv);
+}
+
+void HeightFieldNode::setHeightField(osg::HeightField* heightField)
+{
+    _heightField = heightField;
+    if (_renderer.valid()) _renderer->initialize();
+}
+
+void HeightFieldNode::heightFieldHasBeenModified()
+{
+    if (_renderer.valid()) _renderer->heightFieldHasBeenModified();
+}
+
+void HeightFieldNode::setRenderer(osgTerrain::HeightFieldRenderer* renderer)
+{
+    // need to figure out how to ensure that only one renderer is
+    // used between terrain nodes... issue a warning?
+    _renderer = renderer;
+    
+    if (_renderer.valid())
+    {
+        _renderer->_heightFieldNode = this;
+        _renderer->initialize();
+    }
+}
+
+void HeightFieldNode::computeNormalMap()
+{
+    if (_heightField.valid())
+    {
+        osg::Image* image = new osg::Image;
+        image->allocateImage(_heightField->getNumColumns(),_heightField->getNumRows(),1,GL_RGB,GL_BYTE);
+
+        char* ptr = (char*) image->data();
+        for(unsigned int r=0;r<_heightField->getNumRows();++r)
+        {
+	    for(unsigned int c=0;c<_heightField->getNumColumns();++c)
+	    {
+	        osg::Vec3 normal = _heightField->getNormal(c,r);
+                (*ptr++) = (char)((normal.x()+1.0)*0.5*255);
+                (*ptr++) = (char)((normal.y()+1.0)*0.5*255);
+                (*ptr++) = (char)((normal.z()+1.0)*0.5*255);
+	    }
+        }
+        
+        setNormalMapImage(image);
+        
+    }
+}