//C++ header - Open Scene Graph - Copyright (C) 1998-2002 Robert Osfield
//Distributed under the terms of the GNU Library General Public License (LGPL)
//as published by the Free Software Foundation.

#ifndef OSG_LIGHTMODEL
#define OSG_LIGHTMODEL 1

#include <osg/StateAttribute>
#include <osg/Vec4>

namespace osg {

class SG_EXPORT LightModel : public StateAttribute
{
    public :

        LightModel();

        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
        LightModel(const LightModel& lw,const CopyOp& copyop=CopyOp::SHALLOW_COPY):
          StateAttribute(lw,copyop),
          _ambient(lw._ambient),
          _colorControl(lw._colorControl),
          _localViewer(lw._localViewer),
          _twoSided(lw._twoSided) {}


        META_StateAttribute(osg, LightModel, LIGHTMODEL);

        /** return -1 if *this < *rhs, 0 if *this==*rhs, 1 if *this>*rhs.*/
        virtual int compare(const StateAttribute& sa) const
        {
            // check the types are equal and then create the rhs variable
            // used by the COMPARE_StateAttribute_Paramter macro's below.
            COMPARE_StateAttribute_Types(LightModel,sa)

            // compare each paramter in turn against the rhs.
            COMPARE_StateAttribute_Parameter(_ambient)
            COMPARE_StateAttribute_Parameter(_colorControl)
            COMPARE_StateAttribute_Parameter(_localViewer)
            COMPARE_StateAttribute_Parameter(_twoSided)

            return 0; // passed all the above comparison macro's, must be equal.
        }


        void setAmbientIntensity(const osg::Vec4& ambient) { _ambient = ambient; }
        const osg::Vec4& getAmbientIntensity() const { return _ambient; }


        enum ColorControl
        {
            SEPERATE_SPECULAR_COLOR,
            SINGLE_COLOR
        };
        
        void setColorControl(const ColorControl cc) { _colorControl = cc; }
        inline const ColorControl getColorControl() const { return _colorControl; }


        void setLocalViewer(const bool localViewer) { _localViewer=localViewer; }
        inline const bool getLocalViewer() const { return _localViewer; }


        void setTwoSided(const bool twoSided) { _twoSided = twoSided; }
        inline const bool getTwoSided() const { return _twoSided; }



        virtual void apply(State& state) const;


    protected :

        virtual ~LightModel();

        osg::Vec4 _ambient;
        ColorControl _colorControl;
        bool _localViewer;
        bool _twoSided;

};

}

#endif