RenderBin

/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 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 OSGUTIL_RENDERBIN
#define OSGUTIL_RENDERBIN 1

#include <osgUtil/StateGraph>

#include <map>
#include <vector>
#include <string>

namespace osgUtil {

class RenderStage;
class Statistics;
/**
 * RenderBin base class. Renderbin contains geometries to be rendered as a group, 
 * renderbins are rendered once each.  They can improve efficiency or 
 * use different rendering algorithms.
 * A renderBin can contain further renderBins producing a tree hierarchy of renderBins.
 */
class OSGUTIL_EXPORT RenderBin : public osg::Object
{
    public:

        typedef std::vector<RenderLeaf*>                    RenderLeafList; 
        typedef std::vector<StateGraph*>                    StateGraphList;
        typedef std::map< int, osg::ref_ptr<RenderBin> >    RenderBinList; 

        enum SortMode
        {
            SORT_BY_STATE,
            SORT_BY_STATE_THEN_FRONT_TO_BACK,
            SORT_FRONT_TO_BACK,
            SORT_BACK_TO_FRONT,
            TRAVERSAL_ORDER
        };

        // static methods.
        static RenderBin* createRenderBin(const std::string& binName);
        static RenderBin* getRenderBinPrototype(const std::string& binName);
        static void addRenderBinPrototype(const std::string& binName,RenderBin* proto);
        static void removeRenderBinPrototype(RenderBin* proto);

        static void setDefaultRenderBinSortMode(SortMode mode);
        static SortMode getDefaultRenderBinSortMode();



        RenderBin();

        RenderBin(SortMode mode);

        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
        RenderBin(const RenderBin& rhs,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY);

        virtual osg::Object* cloneType() const { return new RenderBin(); }
        virtual osg::Object* clone(const osg::CopyOp& copyop) const { return new RenderBin(*this,copyop); } // note only implements a clone of type.
        virtual bool isSameKindAs(const osg::Object* obj) const { return dynamic_cast<const RenderBin*>(obj)!=0L; }
        virtual const char* libraryName() const { return "osgUtil"; }
        virtual const char* className() const { return "RenderBin"; }

        virtual void reset();

        void setStateSet(osg::StateSet* stateset) { _stateset = stateset; }
        osg::StateSet* getStateSet() { return _stateset.get(); }
        const osg::StateSet* getStateSet() const { return _stateset.get(); }


        RenderBin* getParent() { return _parent; }
        const RenderBin* getParent() const { return _parent; }

        RenderStage* getStage() { return _stage; }
        const RenderStage* getStage() const { return _stage; }

        int getBinNum() const { return _binNum; }

        StateGraphList& getStateGraphList() { return _stateGraphList; }
        const StateGraphList& getStateGraphList() const { return _stateGraphList; }

        RenderBinList& getRenderBinList() { return _bins; }
        const RenderBinList& getRenderBinList() const { return _bins; }

        RenderLeafList& getRenderLeafList() { return _renderLeafList; }
        const RenderLeafList& getRenderLeafList() const { return _renderLeafList; }


        RenderBin* find_or_insert(int binNum,const std::string& binName);

        void addStateGraph(StateGraph* rg)
        {
            _stateGraphList.push_back(rg);
        }

        virtual void sort();

        virtual void sortImplementation();

        void setSortMode(SortMode mode);
        SortMode getSortMode() const { return _sortMode; }

        virtual void sortByState();
        virtual void sortByStateThenFrontToBack();
        virtual void sortFrontToBack();
        virtual void sortBackToFront();
        virtual void sortTraversalOrder();

        struct SortCallback : public osg::Referenced    
        {
            virtual void sortImplementation(RenderBin*) = 0;
        };

        void setSortCallback(SortCallback* sortCallback) { _sortCallback = sortCallback; }
        SortCallback* getSortCallback() { return _sortCallback.get(); }
        const SortCallback* getSortCallback() const { return _sortCallback.get(); }



        virtual void draw(osg::RenderInfo& renderInfo,RenderLeaf*& previous);

        virtual void drawImplementation(osg::RenderInfo& renderInfo,RenderLeaf*& previous);

        struct DrawCallback : public osg::Referenced    
        {
            virtual void drawImplementation(RenderBin* bin,osg::RenderInfo& renderInfo,RenderLeaf*& previous) = 0;
        };

        void setDrawCallback(DrawCallback* drawCallback) { _drawCallback = drawCallback; }
        DrawCallback* getDrawCallback() { return _drawCallback.get(); }
        const DrawCallback* getDrawCallback() const { return _drawCallback.get(); }

        /** Extract stats for current draw list. */
        bool getStats(Statistics& primStats) const;

        /** Compute the number of dynamic RenderLeaves.*/
        virtual unsigned int computeNumberOfDynamicRenderLeaves() const;

        void copyLeavesFromStateGraphListToRenderLeafList();

        /** If State is non-zero, this function releases any associated OpenGL objects for
           * the specified graphics context. Otherwise, releases OpenGL objexts
           * for all graphics contexts. */
        virtual void releaseGLObjects(osg::State* state= 0) const;

    protected:

        virtual ~RenderBin();
   
        int                             _binNum;
        RenderBin*                      _parent;
        RenderStage*                    _stage;
        RenderBinList                   _bins;
        StateGraphList                  _stateGraphList;
        RenderLeafList                  _renderLeafList;

        bool                            _sorted;           
        SortMode                        _sortMode;
        osg::ref_ptr<SortCallback>      _sortCallback;

        osg::ref_ptr<DrawCallback>      _drawCallback;

        osg::ref_ptr<osg::StateSet>     _stateset;

};

}

#endif