/* -*-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_SECTOR
#define OSGSIM_SECTOR 1

#include <osgSim/Export>

#include <osg/Quat>
#include <osg/Vec3>
#include <osg/Vec4>
#include <osg/Matrix>
#include <osg/Math>
#include <osg/Object>

namespace osgSim {

class Sector : public osg::Object
{
    public:
    
        Sector() {}
        
        Sector(const Sector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            osg::Object(copy,copyop) {}

        virtual const char *libraryName() const { return "osgSim"; }
        virtual const char *className() const { return "Sector"; }
        virtual bool isSameKindAs(const osg::Object *obj) const { return dynamic_cast<const Sector *>(obj) != 0; }
    
        virtual float operator() (const osg::Vec3& /*eyeLocal*/) const = 0;

    protected:

        virtual ~Sector() {}
};

class OSGSIM_EXPORT AzimRange
{
    public:

       AzimRange():
            _cosAzim(1.0f),
            _sinAzim(0.0f),
            _cosAngle(-1.0f),
            _cosFadeAngle(-1.0f) {}
            
        void setAzimuthRange(float minAzimuth,float maxAzimuth,float fadeAngle=0.0f);
        void getAzimuthRange(float& minAzimuth, float& maxAzimuth, float& fadeAngle) const;


        inline float azimSector(const osg::Vec3& eyeLocal) const
        {
            float dotproduct = eyeLocal.x()*_sinAzim+eyeLocal.y()*_cosAzim;
            float length = sqrt(osg::square(eyeLocal.x())+osg::square(eyeLocal.y()));
            if (dotproduct<_cosFadeAngle*length) return 0.0f; // out of sector.
            if (dotproduct>=_cosAngle*length) return 1.0f; // fully in sector.
            return (dotproduct-_cosFadeAngle*length)/((_cosAngle-_cosFadeAngle)*length);
        }

    protected:

        float _cosAzim;
        float _sinAzim;
        float _cosAngle;
        float _cosFadeAngle;
};


class OSGSIM_EXPORT ElevationRange
{
    public:
    
    
        ElevationRange():
            _cosMinElevation(-1.0f),
            _cosMinFadeElevation(-1.0f),
            _cosMaxElevation(1.0),
            _cosMaxFadeElevation(1.0) {}
            
        void setElevationRange(float minElevation,float maxElevation,float fadeAngle=0.0f);
        
        float getMinElevation() const;

        float getMaxElevation() const;

        float getFadeAngle() const;

        inline float elevationSector(const osg::Vec3& eyeLocal) const
        {
            float dotproduct = eyeLocal.z(); // against z axis - eyeLocal*(0,0,1).
            float length = eyeLocal.length();
            if (dotproduct>_cosMaxFadeElevation*length) return 0.0f; // out of sector
            if (dotproduct<_cosMinFadeElevation*length) return 0.0f; // out of sector
            if (dotproduct>_cosMaxElevation*length)
            {
                // in uppoer fade band.
                return (dotproduct-_cosMaxFadeElevation*length)/((_cosMaxElevation-_cosMaxFadeElevation)*length);
            }
            if (dotproduct<_cosMinElevation*length)
            {
                // in lower fade band.
                return (dotproduct-_cosMinFadeElevation*length)/((_cosMinElevation-_cosMinFadeElevation)*length);
            }
            return 1.0f; // fully in sector
        }
        
    protected:

        float _cosMinElevation;
        float _cosMinFadeElevation;
        float _cosMaxElevation;
        float _cosMaxFadeElevation;
};

class OSGSIM_EXPORT AzimSector : public Sector, public AzimRange
{
    public:
    
        AzimSector():
            Sector(),
            AzimRange() {}
    
        AzimSector(const AzimSector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            Sector(copy,copyop),
            AzimRange(copy) {}

        AzimSector(float minAzimuth,float maxAzimuth,float fadeAngle=0.0f);

        META_Object(osgSim,AzimSector);

        virtual float operator() (const osg::Vec3& eyeLocal) const;

    protected:

        virtual ~AzimSector() {}

};

class OSGSIM_EXPORT ElevationSector : public Sector, public ElevationRange
{
    public:
    
    
        ElevationSector():
            Sector(),
            ElevationRange() {}
            
        ElevationSector(const ElevationSector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            Sector(copy,copyop),
            ElevationRange(copy) {}
            
        ElevationSector(float minElevation,float maxElevation,float fadeAngle=0.0f);
    
        META_Object(osgSim,ElevationSector);

        virtual float operator() (const osg::Vec3& eyeLocal) const;
        
    protected:

        virtual ~ElevationSector() {}
};


class OSGSIM_EXPORT AzimElevationSector : public Sector, public AzimRange, public ElevationRange
{
    public:
    
        AzimElevationSector():
            Sector(),
            AzimRange(),
            ElevationRange() {}
    
        AzimElevationSector(const AzimElevationSector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            Sector(copy,copyop),
            AzimRange(copy),
            ElevationRange(copy) {}

        AzimElevationSector(float minAzimuth,float maxAzimuth,float minElevation,float maxElevation,float fadeAngle=0.0f);

        META_Object(osgSim,AzimElevationSector);

        virtual float operator() (const osg::Vec3& eyeLocal) const;

    protected:

        virtual ~AzimElevationSector() {}
};


class OSGSIM_EXPORT ConeSector : public Sector
{
    public:
    
        ConeSector():
            Sector(),
            _axis(0.0f,0.0f,1.0f),
            _cosAngle(-1.0f),
            _cosAngleFade(-1.0f) {}

        ConeSector(const ConeSector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            Sector(copy,copyop),
            _axis(copy._axis),
            _cosAngle(copy._cosAngle),
            _cosAngleFade(copy._cosAngleFade) {}

        ConeSector(const osg::Vec3& axis,float angle,float fadeangle=0.0f);

        META_Object(osgSim,ConeSector);

        void setAxis(const osg::Vec3& axis);
        
        const osg::Vec3& getAxis() const;

        void setAngle(float angle,float fadeangle=0.0f);
        
        float getAngle() const;
    
        float getFadeAngle() const;

        virtual float operator() (const osg::Vec3& eyeLocal) const;

    protected:

        virtual ~ConeSector() {}
    
        osg::Vec3   _axis;
        float       _cosAngle;
        float       _cosAngleFade;
};


/* The DirectionalSector class was created to better handle OpenFlight directional
  lightpoints.  The Elevation and Azimuth Sectors above impose invalid limits on
  the elevation range which cause lightpoints whose direction vectors are not
  on the XY plane to be displayed incorrectly.  Corbin Holtz 4/04 */

class OSGSIM_EXPORT DirectionalSector : public Sector
{
    public:
    
        DirectionalSector():
            Sector(),
            _direction(0.0f, 0.0f, 1.0f),
            _rollAngle(0.0f),
            _cosHorizAngle(-1.0f),
            _cosVertAngle(-1.0f),
            _cosHorizFadeAngle(-1.0f),
            _cosVertFadeAngle(-1.0f) {computeMatrix();}

        DirectionalSector(const DirectionalSector& copy, const osg::CopyOp& copyop = osg::CopyOp::SHALLOW_COPY):
            Sector(copy,copyop),
            _direction(copy._direction),
            _rollAngle(copy._rollAngle),
            _local_to_LP(copy._local_to_LP),
            _cosHorizAngle(copy._cosHorizAngle),
            _cosVertAngle(copy._cosVertAngle),
            _cosHorizFadeAngle(copy._cosHorizFadeAngle),
            _cosVertFadeAngle(copy._cosVertFadeAngle) {}

        DirectionalSector(const osg::Vec3& direction,float horizLobeAngle, float vertLobeAngle, float lobeRollAngle, float fadeAngle=0.0f);

        META_Object(osgSim,DirectionalSector);

        void setDirection(const osg::Vec3& direction);
        
        const osg::Vec3& getDirection() const;

        void setHorizLobeAngle(float angle);
        
        float getHorizLobeAngle() const;
    
        void setLobeRollAngle(float angle);
        
        float getLobeRollAngle() const;
    
        void setVertLobeAngle(float angle);
        
        float getVertLobeAngle() const;
    
        void setFadeAngle(float angle);
            
        float getFadeAngle() const;

        virtual float operator() (const osg::Vec3& eyeLocal) const;

        void computeMatrix() ;

    protected:

        virtual ~DirectionalSector() {}
    
        osg::Vec3   _direction ;
        float       _rollAngle ;
        osg::Matrix _local_to_LP ;
        float       _cosHorizAngle;
        float       _cosVertAngle;
        float       _cosHorizFadeAngle;
        float       _cosVertFadeAngle;
};

}

#endif