#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;
	}
};