//-----------------------------------------------------------------------------+
// Copyright (C), 1998-2007, Beijing Tangent Software Co. Ltd.
// = FileName	:   TPGeEllipse.cpp
// = Version	:   ver2.0
// = Author		:   wlw
// = CreateDate	:   2002-09-09
// = Description:   类的定义
// = Maintainers: 
//                  
//-----------------------------------------------------------------------------+
#include "StdAfx.h"
#include "TPGeEllipse.h"

TPGeEllipse::TPGeEllipse()
{

}

TPGeEllipse::TPGeEllipse(const TGPoint&pt,double aRadius,double bRadius):center(pt),a(aRadius),b(bRadius)
{

}

TPGeEllipse::~TPGeEllipse()
{
	
}

bool TPGeEllipse::IsValid() const
{
	return UP_ZEROD(a) && UP_ZEROD(b);
}

bool TPGeEllipse::IsCircle() const
{
	double temp = a - b;
	return EQUAL_ZEROD(temp);
}

void TPGeEllipse::Pt2Pa(const TGPoint&pt,double&pa) const
{
	pa = TGVector2D(center,pt).GetAngle();
}

void TPGeEllipse::Pa2Pt(double pa,TGPoint&pt) const
{
	pt.x = center.x + a * cos(pa);
	pt.y = center.y + b * sin(pa);
	pt.z = center.z;
}

bool TPGeEllipse::operator != (const TPGeEllipse&e) const
{
	return !(*this == e);
}

GRelation TPGeEllipse::HitTest(const TGPoint&pt) const
{
	double dx = pt.x - center.x, dy = pt.y - center.y;
	double temp = dx * dx / (a * a) + dy * dy / (b * b) - 1;
	if(UP_ZERO(temp))
	{
		return GR_OUTSIDE;
	}
	else if(DOWN_ZERO(temp))
	{
		return GR_INSIDE;
	}
	else
	{
		return GR_IN;
	}
}

bool TPGeEllipse::operator  == (const TPGeEllipse&e) const
{
	double d = a - e.a;
	if(EQUAL_ZEROD(d))
	{
		d = b - e.b;
		if(EQUAL_ZEROD(d))
		{
			return center == e.center;
		}
	}
	return false;
}