多边形填充实验
实验目标:
1.窗口对用户\"左按键\"和\"右按键\"事件的响应 2.实现多边形填充 步骤: 1.运行VC6.0
2.创建工程Fill , (工程类型选择:MFC Wizard (.exe) ) 3. 添加 \"双击左键\"和\"单击右键\"事件的消息响应 (1).选择菜单\"View\"->\"class Wizard\" (2)在弹出的窗口里
classname: 选择CFillView
Messages: 分别选择 WM_LBUTTONDBLCLK , WM_RBUTTONDOWN 然后Add Function 4.修改代码:
(1) 修改fillview.h文件 : 在类的定义中,加入如下代码: public:
CPoint spt[7];
void Floodfill(CPoint s_point, int f_color, int b_color) ;
(2)修改fillview.cpp文件
修改OnDraw,OnLButtonDblClk,OnRButtonDown的三个函数 加入一个函数: Floodfill
void CFillView::OnDraw(CDC* pDC) {
CFillDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc);
CPen newpen(PS_SOLID,1,RGB(255,0,0)); CPen *old=pDC->SelectObject(&newpen);
pDC->TextOut(20,20,\"双击鼠标左键, 出现需填充的多边形\");
pDC->TextOut(20,50,\"进行填充, 需用鼠标右键, 单击多边形内一点, 作为开始填充的种子点\");
pDC->SelectObject(old); }
(2)void CFillView::OnLButtonDblClk(UINT nFlags, CPoint point) {
// TODO: Add your message handler code here and/or call default RedrawWindow(); CDC* pDC=GetDC();
CPen newpen(PS_SOLID,1,RGB(255,0,0)); CPen *old=pDC->SelectObject(&newpen); //多边形各顶点的坐标
spt[0]=CPoint(100,100); spt[1]=CPoint(300,100); spt[2]=CPoint(250,250); spt[3]=CPoint(100,250); spt[4]=CPoint(150,200); spt[5]=CPoint(90,180); spt[6]=CPoint(150,150); spt[7]=CPoint(100,100);
pDC->Polyline(spt,8); //画多边形 pDC->SelectObject(old); ReleaseDC(pDC);
CView::OnLButtonDblClk(nFlags, point); }
void CFillView::OnRButtonDown(UINT nFlags, CPoint point) {
// TODO: Add your message handler code here and/or call default
CView::OnRButtonDown(nFlags, point); int fill=RGB(0,255,0);
int boundary=RGB(255,0,0); Floodfill(point, fill, boundary); } /*
s_point 为种子点
f_color是要填充的颜色, b_color是边界的颜色 */
void CFillView::Floodfill(CPoint s_point, int f_color, int b_color) {
CWindowDC dc (this); int x,y,p0,pmin,pmax;
//求多边形的最大最小值 pmin=pmax=spt[0].y; for(int i=1;i<8;i++) {
if(spt[i].ypmax) pmax=spt[i].y; }x=s_point.x; y=s_point.y; for(;yint current=dc.GetPixel(x,y);while((current!=b_color)&&(current!=f_color)) {
dc.SetPixel(x,y,f_color); x++;
current=dc.GetPixel(x,y); }
x=s_point.x; x--;
current=dc.GetPixel(x,y);
while((current!=b_color)&&(current!=f_color)) {
dc.SetPixel(x,y,f_color); x--;
current=dc.GetPixel(x,y); }
x=s_point.x; }
x=s_point.x; y=s_point.y-1; for(;y>pmin+2;y--) {
int current=dc.GetPixel(x,y);
while((current!=b_color)&&(current!=f_color)) {
dc.SetPixel(x,y,f_color); x++;
current=dc.GetPixel(x,y); }
x=s_point.x; x--;
current=dc.GetPixel(x,y);
while((current!=b_color)&&(current!=f_color)) {
dc.SetPixel(x,y,f_color); x--;
current=dc.GetPixel(x,y); }
x=s_point.x; } }
