//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.
//osgParticle - Copyright (C) 2002 Marco Jez

#ifndef OSGPARTICLE_LINEARINTERPOLATOR_
#define OSGPARTICLE_LINEARINTERPOLATOR_

#include <osgParticle/Interpolator>

#include <osg/CopyOp>
#include <osg/Object>
#include <osg/Vec3>
#include <osg/Vec4>

namespace osgParticle
{

    /// A linear interpolator.
    class LinearInterpolator: public Interpolator {
    public:
        LinearInterpolator()
        : Interpolator() {}
        
        LinearInterpolator(const LinearInterpolator &copy, const osg::CopyOp &copyop = osg::CopyOp::SHALLOW_COPY)
        : Interpolator(copy, copyop) {}
        
        META_Object(osgParticle, LinearInterpolator);
        
        virtual float interpolate(float t, float y1, float y2) const
        {
            return y1 + (y2 - y1) * t;
        }
        
    protected:
        virtual ~LinearInterpolator() {}
    };

}

#endif