//-------------------------------------------------------------------------------------------------------+
// Copyright (C), 1998-2007, Beijing Tangent Software Co. Ltd.
// = FileName	:   TPGeCircle 类 无向圆
// = Version	:   ver2.0
// = Author		:   wlw
// = CreateDate	:   2002-09-09
// = Description:   TPGeCircle 声明 方程:x=center.x+radius*cos(t);y=center.y+radius*sin(t)
// = Maintainers: 
//                  
//-------------------------------------------------------------------------------------------------------+
#ifndef _TPGECIRCLE_H_
#define _TPGECIRCLE_H_

#ifndef _TGPOINT_H_
#include "TGPoint.h"
#endif

#ifndef _TPGELINE2D_H_
#include "TPGeLine2D.h"
#endif

class GEOAPI TPGeCircle
{
public:
	TPGeCircle();
	TPGeCircle(const TGPoint& pt,double radius);
	TPGeCircle(const TGPoint& pt0,const TGPoint& pt1,const TGPoint& pt2);
	TPGeCircle(const TGPoint& pt0,const TGPoint& pt1,double angle);
	virtual ~TPGeCircle();

	void Init(const TGPoint& pt0,const TGPoint& pt1,const TGPoint& pt2);
	void Init(const TGPoint& pt0,const TGPoint& pt1,double angle);

	bool IsValid() const;

	int HitTest(const TGPoint& pt) const;

	void GetDirection(const TGPoint& pt,TGPoint& vt) const;
	void GetDirection(double pa,TGPoint& vt) const;

	void GetTangent(double pa,TPGeLine2D& line) const;

	void Pt2Pa(const TGPoint& pt,double& pa) const;
	void Pa2Pt(double pa,TGPoint& pt) const;

	double Length() const;
	double Area() const;
	double Integration(double pa0,double pa1) const;

	bool operator == (const TPGeCircle& c) const;
	bool operator != (const TPGeCircle& c) const;

	int Intersect(const TPGeLine2D& line,TGPoint& pt1,TGPoint& pt2,bool bNormalized = false) const;
	int Intersect(const TPGeCircle& circle,TGPoint& pt1,TGPoint& pt2) const;

	bool Offset(double nDist);

public:
	TGPoint center;
	double r;

private:
	void InitCircle2D(const TGPoint&pt0,const TGPoint&pt1,double angle,TGPoint&center,double&r);
	void InitCircle2D(const TGPoint&pt0,const TGPoint&pt1,const TGPoint&pt2,TGPoint&center,double&r);
	int CircleInt(const TGPoint&center1,double r1,const TGPoint&center2,double r2,TGPoint&pt1,TGPoint&pt2)const;

};

#endif