source: GTP/branches/IllumWPdeliver2008dec/IlluminationWP/demos/Standalone/PathMap [DirectX]/PointLight.hpp @ 3255

#pragma once
#include "light.hpp"

class PointLight :
        public Light
{
public:
        PointLight(){}
        PointLight(const Vector& position, const Vector& radiance, const Vector& direction)
                : Light(position, radiance)
        {
                this->direction = direction;
        }
        float getFormFactor(const Vector& lookpoint, const Vector& normal) const
        {
                Vector diff; diff.setDifference(lookpoint, position);
                float dist2 = diff.norm2();
                float dist2inv = 1.0f / dist2;
                return - dist2inv * dist2inv * (diff * normal) * (diff * direction);
        }
        Vector getSample() const {return position;}
        bool isPossiblyVisible(const Vector& point) const
        {
                Vector diff; diff.setDifference(point, position);
                return diff * direction > 0;
        }
};