#include "stdafx.h"
#include "HTrackerHandleCalculator.h"

HTrackerHandleCalculator::HTrackerHandleCalculator()
	:m_HandleSize(12)
{
	memset(m_Points, 0, sizeof(m_Points));
}

//创建Tracker矩形的四个角点和中心点
void HTrackerHandleCalculator::Calculate(const CRect & boundRect)
{
	//CRect rc(boundRect);
	//rc.InflateRect(m_OuterMargin, m_OuterMargin);

	m_Points[0].x = m_Points[3].x = boundRect.left;
	m_Points[1].x = m_Points[2].x = boundRect.right;
	m_Points[0].y = m_Points[1].y = boundRect.top;
	m_Points[2].y = m_Points[3].y = boundRect.bottom;

	m_Points[4] = boundRect.CenterPoint();
}

CRect HTrackerHandleCalculator::GetHandleRect(int iHandle)
{
	//if (iHandle == HandleBody) 
		//return m_StartRect;

	CRect rc;
	rc.SetRectEmpty();
	rc.OffsetRect(GetHandlePoint(m_Points, iHandle));
	int d = m_HandleSize / 2;
	rc.InflateRect(d, d);
	return rc;
}

CPoint HTrackerHandleCalculator::GetHandlePoint(int iHandle)
{
	return GetHandlePoint(m_Points, iHandle);
}

POINT HTrackerHandleCalculator::GetCenterPoint()
{
	return m_Points[4];
}

void HTrackerHandleCalculator::Reset()
{
	memset(m_Points, 0, sizeof(m_Points));
}

POINT  HTrackerHandleCalculator::Test(int i)
{
	return m_Points[i];
}
//pPoints为m_PointSrc
CPoint HTrackerHandleCalculator::GetHandlePoint(LPPOINT pPoints, int iHandle)
{
	// Handles are numbered clockwise, like this:
	//
	//		HandleTopLeft	 HandleTop		HandleTopRight
	//				0			1			2
	//				*-----------*-----------*
	//				|						|
	//				|						|
	//  HandleLeft	7 *			* 8			* 3  HandleRight
	//				|		HandleCenter	|
	//				|						|
	//				*-----------*-----------*
	//				6			5			4 
	//	  HandleBottomLeft   HandleBottom	HandleBottomRight
	//
	// The center point is handle 8, the HandleBody is handle 9.

	if (iHandle >= 8)
		return pPoints[4];	// center

	//如果为偶数点，则为角点。
	//m_PointSrc前四个点为角点。iHandle点隔一点就是角点。
	//所以除以2，就获得了iHandle对应的角点的索引。
	int i = iHandle / 2;
	if ((iHandle & 1) == 0)
		return pPoints[i];	// corner

	int j = i + 1;
	if (j > 3) j = 0;

	//求出边线的中点
	CPoint pnt;
	pnt.x = (pPoints[i].x + pPoints[j].x) / 2;
	pnt.y = (pPoints[i].y + pPoints[j].y) / 2;
	return pnt;		// edge
}