#ifndef OSG_FOG
#define OSG_FOG 1

#include <osg/GL>
#include <osg/Vec4>
#include <osg/Types>
#include <osg/Object>

namespace osg {


/** Fog - encapsulates OpenGL fog state. */ 
class SG_EXPORT Fog : public Object
{
    public :

        enum FogMode {
            LINEAR = GL_LINEAR,
            EXP    = GL_EXP,
            EXP2   = GL_EXP2
        };

        Fog( void );
        static Fog* instance();
        virtual Object* clone() const { return new Fog(); }
        virtual bool isSameKindAs(Object* obj) { return dynamic_cast<Fog*>(obj)!=NULL; }
        virtual const char* className() const { return "Fog"; }

        static void enable( void );
        static void disable( void );
        void apply( void );

        void  setMode( uint mode ) { _mode = mode; }
        uint getMode( void ) { return _mode; }

        void  setDensity( float density ) { _density = density; }
        float getDensity( void ) { return _density; }

        void  setStart( float start ) { _start = start; }
        float getStart( void ) { return _start; }

        void  setEnd( float end ) { _end = end; }
        float getEnd( void )      { return _end; }

        void  setColor( Vec4 &color )
        {
            _color[0] = color[0];
            _color[1] = color[1];
            _color[2] = color[2];
            _color[3] = color[3];
        }

    protected :

        virtual ~Fog( void );

        uint   _mode;
        float  _density;
        float  _start;
        float  _end;
        Vec4 _color;
};

};

#endif