Impostor.h

Go to the documentation of this file.

/* -*-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 OSGSIM_IMPOSTOR
#define OSGSIM_IMPOSTOR 1

#include <osg/LOD>
#include <osg/buffered_value>

#include <osgUtil/CullVisitor>

#include <osgSim/ImpostorSprite>

namespace osgSim {

class OSGSIM_EXPORT Impostor : public osg::LOD
{
    public :
        Impostor();

        Impostor(const Impostor& es, const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY):
            osg::LOD(es,copyop),
            _impostorThreshold(es._impostorThreshold) {}

        META_Node(osgSim, Impostor);

        virtual void traverse(osg::NodeVisitor& nv);

        typedef std::vector< osg::ref_ptr<ImpostorSprite> > ImpostorSpriteList;

        inline void setImpostorThreshold(float distance) { _impostorThreshold = distance; }

        /* Get the Impostor threshold distance. */
        inline float getImpostorThreshold() const { return _impostorThreshold; }

        inline void setImpostorThresholdToBound(float ratio=1.0f) { _impostorThreshold = getBound().radius()*ratio; }

        ImpostorSprite* findBestImpostorSprite(unsigned int contextID, const osg::Vec3& currLocalEyePoint) const;

        void addImpostorSprite(unsigned int contextID, ImpostorSprite* is);

        inline ImpostorSpriteList& getImpostorSpriteList(unsigned int contexID) { return _impostorSpriteListBuffer[contexID]; }

        inline const ImpostorSpriteList& getImpostorSpriteList(unsigned int contexID) const { return _impostorSpriteListBuffer[contexID]; }

        virtual osg::BoundingSphere computeBound() const;

    protected :

        virtual ~Impostor() {}

        mutable osg::buffered_object<ImpostorSpriteList>  _impostorSpriteListBuffer;

        ImpostorSprite* createImpostorSprite(osgUtil::CullVisitor* cv);

        float _impostorThreshold;

};

}

#endif