画点-画线-移动点(鼠标左键按下-鼠标右键按下-鼠标移动)

画点-画线-移动点(鼠标左键按下-鼠标右键按下-鼠标移动) DrawGraphView.h typedef struct tagPoint //定义点结构 { float x; float y; }PNT_INFO; typedef struct tagLine //定义线结构 { PNT_INFO pnt[100]; long num; }LIN_INFO; class CDrawGraphView : public CView { public: short m_iDrawMode; //画图模式(初始:0; 画点:1; 画线:2; 移点:3) long m_pointNum; //点数 long m_lineNum; //线数 long m_linepntNum; //一条线上的点数 int m_iNo; //移动点时，离鼠标最近距离点的点号(下标) public: PNT_INFO m_point[100]; //点数组:装点的个数 LIN_INFO m_line[100]; //线数组:装线的条数 PNT_INFO m_linepnt[100]; //线点数组:一条线上的点数 }; DrawGraphView.cpp #include //求距离中用到开平方运算 static long startx = 0; //起点:x static long starty = 0; //起点:y static long endx = 0; //终点:x static long endy = 0; //终点:y static short flagCap = 0; //标志:画线时记录鼠标捕获状态 static short flagMovePnt = 0; //标志:点移动 int CalcMinDist(PNT_INFO* pPnt,int num, PNT_INFO& pnt) //求所有点中，离鼠标点最近的点下标 { float fTmp=0,fDist=99999; int iNo = -1; if(pPnt==NULL||num<=0) return -1; 1 for(int i=0;iSelectObject(&pen); pDC->SetROP2(R2_NOTXORPEN ); switch(m_iDrawMode) //绘图模式 { case 1: case 3: //画点和移动点 for(i=0;iRectangle((int)m_point[i].x-5,(int)m_point[i].y-5,(int)m_point[i].x+5,(int)m_point[i]. y+5); break; case 2: //画线 for(i=0;iMoveTo((int)m_line[i].pnt[j].x,(int)m_line[i].pnt[j].y); pDC->LineTo((int)m_line[i].pnt[j+1].x,(int)m_line[i].pnt[j+1].y); } } break; default: break; } } 2 void CDrawGraphView::OnDrawDrawpoint() //画点消息处理 { // TODO: Add your command handler code here m_iDrawMode = 1; //设置画点模式 } void CDrawGraphView::OnDrawDrawline() //画线消息处理 { // TODO: Add your command handler code here m_iDrawMode = 2; //设置画线模式 } void CDrawGraphView::OnDrawMovepoint() //移动点消息处理 { // TODO: Add your command handler code here m_iDrawMode = 3; //设置移动点模式 } void CDrawGraphView::OnLButtonDown(UINT nFlags, CPoint point) //鼠标左键按下消息处理 { // TODO: Add your message handler code here and/or call default CDC* pDC = GetDC(); //获取设备环境 CPen pen, *pOldPen=NULL; //定义画笔 pDC->SetROP2(R2_NOTXORPEN ); //设置绘图模式(异或) pOldPen = pDC->SelectObject(&pen); //将新画笔选入设备环境，并保存旧画笔 if(m_iDrawMode == 1) //如果画点 { m_point[m_pointNum].x = (float)point.x; //将点的x坐标放入点数组 m_point[m_pointNum].y = (float)point.y; //将点的y坐标放入点数组 pDC->Rectangle((int)m_point[m_pointNum].x-5,(int)m_point[m_pointNum].y-5,(int)m_point[m_poi ntNum].x+5,(int)m_point[m_pointNum].y+5); //在该点画小矩形 m_pointNum++; //点数增1 } if(m_iDrawMode == 2) //如果画线 { startx = point.x; //将鼠标点分别赋给起点和终点 starty = point.y; endx = point.x; endy = point.y; pDC->MoveTo(startx,starty); //抬笔到起点 pDC->LineTo(endx,endy); //落笔到终点 m_linepnt[m_linepntNum].x = (float)point.x; //将鼠标点放入线数组 m_linepnt[m_linepntNum].y = (float)point.y; m_linepntNum++; //线数组中的点数增1 SetCapture(); //设置有效区域的捕获方式 flagCap = 1; //抓线标志置1(0:第一个点; 1:非第一个点) } if(m_iDrawMode == 3) //如果是移动点 { if(flagMovePnt==0) 3 { flagMovePnt = 1; //移动点标志置1 PNT_INFO pnt; pnt.x = (float)point.x; //将鼠标点放入点结构体变量 pnt.y = (float)point.y; //需要加入求距离最短点的函数，返回点数组下标; m_iNo = CalcMinDist(m_point,m_pointNum,pnt); //调函数求出离鼠标点最近点的下标 SetCapture(); //设置有效区域的捕获方式 } else { flagMovePnt = 0; ::ReleaseCapture(); //释放捕获 } } pDC->SelectObject(pOldPen); //选回旧画笔 ReleaseDC(pDC); //释放设备环境 CView::OnLButtonDown(nFlags, point); } void CDrawGraphView::OnRButtonDown(UINT nFlags, CPoint point) //鼠标右键按下消息处理 { // TODO: Add your message handler code here and/or call default CDC* pDC = GetDC(); //获取设备环境 CPen pen, *pOldPen=NULL; //定义画笔 pDC->SetROP2(R2_NOTXORPEN ); //设置绘图模式 pOldPen = pDC->SelectObject(&pen); //将画笔选入设备环境，并保存旧画笔 if(m_iDrawMode == 2) //如果画线 { pDC->MoveTo(startx,starty); //抬笔到起点 pDC->LineTo(endx,endy); //落笔到终点 endx = point.x; endy = point.y; flagCap = 0; for(int i=0;iSelectObject(pOldPen); //将旧画笔选入设备环境，为退出绘图作准备 ReleaseDC(pDC); //释放设备环境 CView::OnRButtonDown(nFlags, point); } void CDrawGraphView::OnMouseMove(UINT nFlags, CPoint point) //鼠标移动消息处理 { // TODO: Add your message handler code here and/or call default CDC* pDC = GetDC(); //获取设备环境 CPen pen, *pOldPen=NULL; //定义画笔 pDC->SetROP2(R2_NOTXORPEN); //设置绘图模式 pOldPen = pDC->SelectObject(&pen); //将画笔选入设备环境，并保存旧画笔 if(m_iDrawMode == 2) //如果画线，进行橡皮筋方式画线 { if(flagCap==1) { pDC->MoveTo(startx,starty); //擦除线(异或方式画) pDC->LineTo(endx,endy); endx = point.x; //记下新的点(鼠标点) endy = point.y; pDC->MoveTo(startx,starty); //画新线(从原始起点到鼠标点间画橡皮筋线) pDC->LineTo(endx,endy); } } if(m_iDrawMode == 3) //如果移动点 { if(m_iNo<0) //点的下标异常处理 goto lab; //跳转到标号lab处 if(flagMovePnt==1) { //擦除离鼠标最近点的小矩形 pDC->Rectangle(m_point[m_iNo].x-5,m_point[m_iNo].y-5,m_point[m_iNo].x+5,m_point[m_iNo].y+5); m_point[m_iNo].x = point.x; //将该点坐标写回到点数组中 m_point[m_iNo].y = point.y; //在移动鼠标点画小矩形 pDC->Rectangle(m_point[m_iNo].x-5,m_point[m_iNo].y-5,m_point[m_iNo].x+5,m_point[m_iNo].y+5); } } lab: pDC->SelectObject(pOldPen); //将旧画笔选入设备环境，为退出绘图作准备 ReleaseDC(pDC); //释放设备环境 CView::OnMouseMove(nFlags, point); } 5