鼠标移动轨迹判定

Question

问题描述：鼠标左键down，鼠标move，释放鼠标，左键UP，在这一系列过程中，我记录下了鼠标移动的每个点的坐标。怎样通过这些坐标来精确的判断出，鼠标是顺时针移动的还是逆时针移动的？各位同志给点好的思路啊。我自己实现了一个，但效果不是特别好。期待各位的答案。

Answer 1

#ifndef JUDGEDIRECTION_H__
#define JUDGEDIRECTION_H__
#include <Windows.h>
#include <vector>
typedef enum {CLOCKWISE=0,COUNTER_CLOCKWISE,ERROR_DIRECTION} MouseMoveDirection;class CMouseMoveDirection
{
public:
CMouseMoveDirection();
MouseMoveDirection GetMouseMoveDirection(const std::vector<POINT>& pPoint,int nNumOfPoints,int nAccuracy=1);
private:
bool IsClockwise();
bool IsCounterClockwise();
void FindTopBottomLeftRightPoint();
private:
int m_nNumOfPoints;
int m_nAccuracy;
PPOINT m_pOriginalPoint;
int m_nIndexOfToppestPoint;
int m_nIndexOfBottomestPoint;
int m_nIndexOfLeftestPoint;
int m_nIndexOfRightestPoint;
};#endif//JUDGEDIRECTION_H__

Answer 2

#include "stdafx.h"
#include "JudgeDirection.h"CMouseMoveDirection::CMouseMoveDirection()
{
m_nNumOfPoints = 0;
m_nAccuracy = 0;
m_pOriginalPoint = NULL;
m_nIndexOfToppestPoint = 0;
m_nIndexOfBottomestPoint = 0;
m_nIndexOfLeftestPoint = 0;
m_nIndexOfRightestPoint = 0;
}bool CMouseMoveDirection::IsClockwise()
{
if ((m_nIndexOfLeftestPoint<m_nIndexOfToppestPoint)
&&(m_nIndexOfToppestPoint<m_nIndexOfRightestPoint))
{
return true;
}else if ((m_nIndexOfBottomestPoint<m_nIndexOfLeftestPoint)&&
(m_nIndexOfLeftestPoint<m_nIndexOfToppestPoint))
{
return true;
}else if((m_nIndexOfRightestPoint<m_nIndexOfBottomestPoint)&&
(m_nIndexOfBottomestPoint<m_nIndexOfLeftestPoint))
{
return true;
}else if ((m_nIndexOfToppestPoint<m_nIndexOfRightestPoint)&&
(m_nIndexOfRightestPoint<m_nIndexOfBottomestPoint))
{
return true;
}else
{
return false;
}
}bool CMouseMoveDirection::IsCounterClockwise()
{
if ((m_nIndexOfLeftestPoint<m_nIndexOfBottomestPoint)&&
(m_nIndexOfBottomestPoint<m_nIndexOfRightestPoint))
{
return true;
} else if ((m_nIndexOfBottomestPoint<m_nIndexOfRightestPoint)&&
m_nIndexOfRightestPoint<m_nIndexOfToppestPoint)
{
return true;
} else if (m_nIndexOfRightestPoint<m_nIndexOfToppestPoint
&&m_nIndexOfToppestPoint<m_nIndexOfLeftestPoint)
{
return true;
} else if ((m_nIndexOfToppestPoint<m_nIndexOfLeftestPoint)
&&(m_nIndexOfLeftestPoint<m_nIndexOfBottomestPoint))
{
return true;
} else
{
return false;
}
}
void CMouseMoveDirection::FindTopBottomLeftRightPoint()
{
POINT TempTopPoint,TempBottomPoint,TempLeftPoint,TempRightPoint;
TempTopPoint = *m_pOriginalPoint;
TempBottomPoint = *m_pOriginalPoint;
TempLeftPoint = *m_pOriginalPoint;
TempRightPoint = *m_pOriginalPoint;
PPOINT pPoint = m_pOriginalPoint;
int nNum = m_nNumOfPoints -10;
for (int i=0;i<nNum;i+=m_nAccuracy,pPoint+=m_nAccuracy)
{
if (pPoint->y<TempTopPoint.y)
{
TempTopPoint.y = pPoint->y;
TempTopPoint.x = pPoint->x;
m_nIndexOfToppestPoint = i;
}
if (pPoint->y>TempBottomPoint.y)
{
TempBottomPoint.y = pPoint->y;
TempBottomPoint.x = pPoint->x;
m_nIndexOfBottomestPoint = i;
}
if (pPoint->x<TempLeftPoint.x)
{
TempLeftPoint.x = pPoint->x;
TempLeftPoint.y = pPoint->y;
m_nIndexOfLeftestPoint = i;
}
if (pPoint->x>TempRightPoint.x)
{
TempRightPoint.x = pPoint->x;
TempRightPoint.y = pPoint->y;
m_nIndexOfRightestPoint = i;
}
}
}MouseMoveDirection CMouseMoveDirection::GetMouseMoveDirection(const std::vector<POINT>& pPoint,int nNumOfPoints,int nAccuracy/* =1 */)
{
if (pPoint.size()<10)
{
return ERROR_DIRECTION;
} m_nNumOfPoints = nNumOfPoints;
m_nAccuracy = nAccuracy;
m_pOriginalPoint = (PPOINT)&pPoint[0]; FindTopBottomLeftRightPoint(); if (IsClockwise())
{
return CLOCKWISE;
}
else if (IsCounterClockwise())
{
return COUNTER_CLOCKWISE;
}
else
{
return ERROR_DIRECTION;
}
}