Added new osgVolume::VolumeScene and osgVolume::MultipassTechnique class shells that will be filled out to provide multi-pass volume rendering that handles mixing of

3D meshes with volume rendering and segmentation of volumes via a user defined hull mesh.

examples/osgvolume/osgvolume.cpp

@@ -69,6 +69,8 @@
 #include <osgVolume/VolumeTile>
 #include <osgVolume/RayTracedTechnique>
 #include <osgVolume/FixedFunctionTechnique>
+#include <osgVolume/MultipassTechnique>
+#include <osgVolume/VolumeScene>
 
 enum ShadingModel
 {
@@ -437,6 +439,9 @@ int main( int argc, char **argv )
     arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display this information");
     arguments.getApplicationUsage()->addCommandLineOption("--images [filenames]","Specify a stack of 2d images to build the 3d volume from.");
     arguments.getApplicationUsage()->addCommandLineOption("--shader","Use OpenGL Shading Language. (default)");
+    arguments.getApplicationUsage()->addCommandLineOption("--multi-pass","Use MultipassTechnique to render volumes.");
+    arguments.getApplicationUsage()->addCommandLineOption("--model","load 3D model and insert into the scene along with the volume.");
+    arguments.getApplicationUsage()->addCommandLineOption("--hull","load 3D hull that defines the extents of the region to volume render.");
     arguments.getApplicationUsage()->addCommandLineOption("--no-shader","Disable use of OpenGL Shading Language.");
     arguments.getApplicationUsage()->addCommandLineOption("--gpu-tf","Aply the transfer function on the GPU. (default)");
     arguments.getApplicationUsage()->addCommandLineOption("--cpu-tf","Apply the transfer function on the CPU.");
@@ -618,11 +623,36 @@ int main( int argc, char **argv )
     bool useManipulator = false;
     while(arguments.read("--manipulator") || arguments.read("-m")) { useManipulator = true; }
 
-
     bool useShader = true;
     while(arguments.read("--shader")) { useShader = true; }
     while(arguments.read("--no-shader")) { useShader = false; }
 
+    bool useMultipass = false;
+    while(arguments.read("--multi-pass")) useMultipass = true;
+
+    std::string filename;
+    osg::ref_ptr<osg::Group> models;
+    while(arguments.read("--model",filename))
+    {
+        osg::ref_ptr<osg::Node> model = osgDB::readNodeFile(filename);
+        if (model.valid())
+        {
+            if (!models) models = new osg::Group;
+            models->addChild(model.get());
+        }
+    }
+
+    osg::ref_ptr<osg::Group> hulls;
+    while(arguments.read("--hull",filename))
+    {
+        osg::ref_ptr<osg::Node> hull = osgDB::readNodeFile(filename);
+        if (hull.valid())
+        {
+            if (!hulls) hulls = new osg::Group;
+            hulls->addChild(hull.get());
+        }
+    }
+
     bool gpuTransferFunction = true;
     while(arguments.read("--gpu-tf")) { gpuTransferFunction = true; }
     while(arguments.read("--cpu-tf")) { gpuTransferFunction = false; }
@@ -1098,7 +1128,14 @@ int main( int argc, char **argv )
         layer->addProperty(sp);
 
 
-        tile->setVolumeTechnique(new osgVolume::RayTracedTechnique);
+        if (useMultipass)
+        {
+            tile->setVolumeTechnique(new osgVolume::MultipassTechnique);
+        }
+        else
+        {
+            tile->setVolumeTechnique(new osgVolume::RayTracedTechnique);
+        }
     }
     else
     {
@@ -1165,6 +1202,28 @@ int main( int argc, char **argv )
             loadedModel = group;
         }
 
+        if (hulls.get())
+        {
+            tile->addChild(hulls.get());
+        }
+
+        // add add models into the scene alongside the volume
+        if (models.get())
+        {
+            osg::ref_ptr<osg::Group> group = new osg::Group;
+            group->addChild(models.get());
+            group->addChild(loadedModel.get());
+            loadedModel = group.get();
+        }
+
+        // if we want to do multi-pass volume rendering we need decorate the whole scene with a VolumeScene node.
+        if (useMultipass)
+        {
+            osg::ref_ptr<osgVolume::VolumeScene> volumeScene = new osgVolume::VolumeScene;
+            volumeScene->addChild(loadedModel.get());
+            loadedModel = volumeScene.get();
+        }
+
 
         // set the scene to render
         viewer.setSceneData(loadedModel.get());

include/osgVolume/MultipassTechnique

@@ -0,0 +1,60 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2009 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.
+*/
+
+#ifndef OSGVOLUME_MULTIPASSTECHNIQUE
+#define OSGVOLUME_MULTIPASSTECHNIQUE 1
+
+#include <osgVolume/VolumeTechnique>
+#include <osg/MatrixTransform>
+
+namespace osgVolume {
+
+class OSGVOLUME_EXPORT MultipassTechnique : public VolumeTechnique
+{
+    public:
+
+        MultipassTechnique();
+
+        MultipassTechnique(const MultipassTechnique&,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
+
+        META_Object(osgVolume, MultipassTechnique);
+
+        virtual void init();
+
+        virtual void update(osgUtil::UpdateVisitor* nv);
+
+        virtual void cull(osgUtil::CullVisitor* nv);
+
+        /** Clean scene graph from any terrain technique specific nodes.*/
+        virtual void cleanSceneGraph();
+
+        /** Traverse the terrain subgraph.*/
+        virtual void traverse(osg::NodeVisitor& nv);
+
+    protected:
+
+        virtual ~MultipassTechnique();
+
+        osg::ref_ptr<osg::MatrixTransform> _transform;
+
+        typedef std::map<osgUtil::CullVisitor::Identifier*, osg::Matrix> ModelViewMatrixMap;
+
+        OpenThreads::Mutex _mutex;
+        ModelViewMatrixMap _modelViewMatrixMap;
+
+        osg::ref_ptr<osg::StateSet> _whenMovingStateSet;
+};
+
+}
+
+#endif

include/osgVolume/VolumeScene

@@ -0,0 +1,44 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2009 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.
+*/
+
+#ifndef OSGVOLUMESCENE
+#define OSGVOLUMESCENE 1
+
+#include <osg/Group>
+#include <osgVolume/Export>
+
+namespace osgVolume {
+
+/** VolumeScene provides high level support for doing multi-pass rendering of volumes where the main scene to rendered to color and depth textures and then re-rendered for the purposes of volume rendering.*/
+class OSGVOLUME_EXPORT VolumeScene : public osg::Group
+{
+    public:
+
+        VolumeScene();
+
+        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
+        VolumeScene(const VolumeScene&,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);
+
+        META_Node(osgVolume, VolumeScene);
+
+        virtual void traverse(osg::NodeVisitor& nv);
+
+    protected:
+
+        virtual ~VolumeScene();
+
+};
+
+}
+
+#endif

src/osgVolume/CMakeLists.txt

@@ -12,10 +12,12 @@ SET(TARGET_H
     ${HEADER_PATH}/FixedFunctionTechnique
     ${HEADER_PATH}/Layer
     ${HEADER_PATH}/Locator
+    ${HEADER_PATH}/MultipassTechnique
     ${HEADER_PATH}/Property
     ${HEADER_PATH}/RayTracedTechnique
     ${HEADER_PATH}/Version
     ${HEADER_PATH}/Volume
+    ${HEADER_PATH}/VolumeScene
     ${HEADER_PATH}/VolumeTechnique
     ${HEADER_PATH}/VolumeTile
 )
@@ -25,17 +27,19 @@ SET(TARGET_SRC
     FixedFunctionTechnique.cpp
     Layer.cpp
     Locator.cpp
+    MultipassTechnique.cpp
     Property.cpp
     RayTracedTechnique.cpp
     Version.cpp
     Volume.cpp
+    VolumeScene.cpp
     VolumeTechnique.cpp
     VolumeTile.cpp
     ${OPENSCENEGRAPH_VERSIONINFO_RC}
 )
 
 
-SET(TARGET_LIBRARIES 
+SET(TARGET_LIBRARIES
     osgUtil
     osgDB
     osgGA

src/osgVolume/MultipassTechnique.cpp

@@ -0,0 +1,124 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2009 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 <osgVolume/MultipassTechnique>
+#include <osgVolume/VolumeTile>
+
+#include <osg/Geometry>
+#include <osg/io_utils>
+
+#include <osg/Program>
+#include <osg/TexGen>
+#include <osg/Texture1D>
+#include <osg/Texture2D>
+#include <osg/Texture3D>
+#include <osg/TransferFunction>
+
+#include <osgDB/ReadFile>
+#include <osgDB/WriteFile>
+
+namespace osgVolume
+{
+
+
+MultipassTechnique::MultipassTechnique()
+{
+}
+
+MultipassTechnique::MultipassTechnique(const MultipassTechnique& fft,const osg::CopyOp& copyop):
+    VolumeTechnique(fft,copyop)
+{
+}
+
+MultipassTechnique::~MultipassTechnique()
+{
+}
+
+void MultipassTechnique::init()
+{
+    OSG_INFO<<"MultipassTechnique::init()"<<std::endl;
+
+    if (!_volumeTile)
+    {
+        OSG_NOTICE<<"MultipassTechnique::init(), error no volume tile assigned."<<std::endl;
+        return;
+    }
+
+    if (_volumeTile->getLayer()==0)
+    {
+        OSG_NOTICE<<"MultipassTechnique::init(), error no layer assigend to volume tile."<<std::endl;
+        return;
+    }
+
+    if (_volumeTile->getLayer()->getImage()==0)
+    {
+        OSG_NOTICE<<"MultipassTechnique::init(), error no image assigned to layer."<<std::endl;
+        return;
+    }
+
+    OSG_NOTICE<<"MultipassTechnique::init() Need to set up"<<std::endl;
+}
+
+void MultipassTechnique::update(osgUtil::UpdateVisitor* /*uv*/)
+{
+//    OSG_NOTICE<<"MultipassTechnique:update(osgUtil::UpdateVisitor* nv):"<<std::endl;
+}
+
+void MultipassTechnique::cull(osgUtil::CullVisitor* cv)
+{
+    OSG_NOTICE<<"MultipassTechnique::cull() Need to set up"<<std::endl;
+}
+
+void MultipassTechnique::cleanSceneGraph()
+{
+    OSG_NOTICE<<"MultipassTechnique::cleanSceneGraph()"<<std::endl;
+}
+
+void MultipassTechnique::traverse(osg::NodeVisitor& nv)
+{
+    // OSG_NOTICE<<"MultipassTechnique::traverse(osg::NodeVisitor& nv)"<<std::endl;
+    if (!_volumeTile) return;
+
+    // if app traversal update the frame count.
+    if (nv.getVisitorType()==osg::NodeVisitor::UPDATE_VISITOR)
+    {
+        if (_volumeTile->getDirty()) _volumeTile->init();
+
+        osgUtil::UpdateVisitor* uv = dynamic_cast<osgUtil::UpdateVisitor*>(&nv);
+        if (uv)
+        {
+            update(uv);
+            return;
+        }
+
+    }
+    else if (nv.getVisitorType()==osg::NodeVisitor::CULL_VISITOR)
+    {
+        osgUtil::CullVisitor* cv = dynamic_cast<osgUtil::CullVisitor*>(&nv);
+        if (cv)
+        {
+            cull(cv);
+            return;
+        }
+    }
+
+
+    if (_volumeTile->getDirty())
+    {
+        OSG_INFO<<"******* Doing init ***********"<<std::endl;
+        _volumeTile->init();
+    }
+}
+
+
+} // end of osgVolume namespace

src/osgVolume/VolumeScene.cpp

@@ -0,0 +1,36 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2009 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 <osgVolume/VolumeScene>
+#include <OpenThreads/ScopedLock>
+
+using namespace osgVolume;
+
+VolumeScene::VolumeScene()
+{
+}
+
+VolumeScene::VolumeScene(const VolumeScene& vs, const osg::CopyOp& copyop):
+    osg::Group(vs,copyop)
+{
+}
+
+
+VolumeScene::~VolumeScene()
+{
+}
+
+void VolumeScene::traverse(osg::NodeVisitor& nv)
+{
+    Group::traverse(nv);
+}