二维区域扫描线填充算法.doc

二维区域扫描线填充算法的实现这个程序从一放暑假就开始做，直做到今天，花了1个星期的时间，真是不应该啊，唉，谁让咱编程技术不太好呢，得，闲话少说。关于区域填充，我们常用的算法有扫描线填充算法以及种子填充算法，我现在只完成了前一种，后一种等过两天实现之，扫描算法的理解不难，可是实现起来有许多细节问题还是有点烦琐，下面这个是非常粗糙的一个版本，只能说是实现了所需，代码一点也不好，到处充斥着各种命名模糊的变量，又不很多注释，谁要是想看，那肯定费很大劲，不过整体结构是正确的。我本来想把整个算法详细地一步一步列出来，可是要讲解算法的话，还要画很多图，还要贴上来，就此做罢，如果谁也在做这个程序，就在下面留下评论即可，我一定在最短时间内给你回复。下面是我的代码，直接CTRL+V到VC6中就可以看到效果了：(通过这个程序我还发现，当代码一上500行，变量就开始混淆了，尤其是用来控制循环的那些小变量，还有就是在这个程序中我初步使用了VC6的调试功能 ，确实非常方便，但还有些功能不清楚，唉，慢慢来吧)下面是一个简单的填充效果： /#include #include #define FILLING 1#define RESET 2typedef struct int xStart,yStart; int xEnd,yEnd; LINE,*PLINE;LINE lines100;LINE line;static int j=0;POINT draw_refresh1000;static int l=0;LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE prevInstance,PSTR szCmdLine,int iCmdShow)static TCHAR szAppName=2D Region Filling; HWND hwnd; MSG msg; WNDCLASS wndclass;for(int i=0;i100;i+)linesi.xStart=0;linesi.yStart=0;linesi.xEnd=0;linesi.yEnd=0;wndclass.style=CS_HREDRAW | CS_VREDRAW |CS_DBLCLKS; wndclass.lpfnWndProc=WndProc; wndclass.cbClsExtra=0; wndclass.cbWndExtra=0; wndclass.hInstance=hInstance; wndclass.hIcon=LoadIcon(NULL,IDI_APPLICATION); wndclass.hCursor=LoadCursor(NULL,IDC_CROSS); wndclass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);wndclass.lpszMenuName=NULL; wndclass.lpszClassName=szAppName; if(!RegisterClass(&wndclass)MessageBox(NULL,Regist window class failed!,Error,MB_OK);hwnd=CreateWindow(szAppName,2D Region Filling,WS_OVERLAPPED | WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,hInstance,NULL);ShowWindow(hwnd,iCmdShow); UpdateWindow(hwnd); while(GetMessage(&msg,NULL,0,0) TranslateMessage(&msg); DispatchMessage(&msg); return msg.wParam; LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam) HWND hButtonFilling;HWND hButtonReset;int cxChar=0;int cyChar=0;static PLINE head=lines;int i=0;HDC hdc; PAINTSTRUCT ps; RECT clientrect;POINT need_draw=0,0;POINT draw100;int b=0;static int filled=0;for(int e=0;ehInstance,NULL);hButtonReset =CreateWindow(TEXT(BUTTON),Reset, WS_CHILD | WS_VISIBLE | BS_DEFPUSHBUTTON,70*cxChar,28*cyChar,20*cxChar,7*cyChar/4,hwnd,(HMENU)RESET, (LPCREATESTRUCT)lParam)-hInstance,NULL);return 0;case WM_LBUTTONDOWN:/ SetCapture(hwnd);line.xStart=(int)LOWORD(lParam);line.yStart=(int)HIWORD(lParam);for(i=0;j=1 & ilinesi.xStart-30) & (line.xStartlinesi.yStart-30) & (line.yStartlinesi.xEnd-30) & (line.xStartlinesi.yEnd-30) & (line.yStart=1 & ilinesi.xStart-30) & (line.xEndlinesi.yStart-30) & (line.yEndlinesi.xEnd-30) & (line.xEndlinesi.yEnd-30) & (line.yEndlinesi.yEnd+30)hdc=GetDC(hwnd);SelectObject(hdc,GetStockObject(WHITE_PEN);/clear the last black line if find a adjacent vetexMoveToEx(hdc,line.xStart,line.yStart,NULL);LineTo(hdc,line.xEnd,line.yEnd);line.xEnd=linesi.xEnd;line.yEnd=linesi.yEnd;SelectObject(hdc,GetStockObject(BLACK_PEN);MoveToEx(hdc,line.xStart,line.yStart,NULL);LineTo(hdc,line.xEnd,line.yEnd);ReleaseDC(hwnd,hdc);linesj.xStart=line.xStart;linesj.yStart=line.yStart;linesj.xEnd=line.xEnd;linesj.yEnd=line.yEnd;j+;line.xStart=0;line.yStart=0;line.xEnd=0;line.yEnd=0;/ ReleaseCapture();return 0;case WM_COMMAND:switch(LOWORD(wParam)case FILLING:smallest_y=lines0.yStart;lardgest_y=lines0.yStart;for(h=0;h=100;h+)drawh.x=0;drawh.y=0;filled=1;for(h=0;hj;h+)/find the smallest y coordinate of the edgesif(linesh.yStartsmallest_y)smallest_y=linesh.yStart;if(linesh.yEndsmallest_y)smallest_y=linesh.yEnd;for(h=0;hlardgest_y)lardgest_y=linesh.yStart;if(linesh.yEndlardgest_y)lardgest_y=linesh.yEnd;for(k=smallest_y;k=lardgest_y;k+)/check every scan line to filling the regionfor(m=0;mlinesm.yEnd ? linesm.yStart:linesm.yEnd ;c=linesm.yStarta)continue; else if(kc)continue; else if(linesm.yStart=linesm.yEnd & k=linesm.yStart)continue;elsex=0;if(linesm.yStart=k)for(n=0;nlinesm.yStart & linesn.yEndlinesm.yStart) | (linesm.yEndlinesm.yStart & linesn.yEndlinesm.yStart)x=linesm.xStart;drawb.x=x;drawb.y=k;b+;drawb.x=x;drawb.y=k;b+;else/ MessageBox(hwnd,error2,error2,MB_OK);x=linesm.xStart;flag=0;for(h=0;hlinesm.yStart & linesn.yStartlinesm.yStart) | (linesm.yEndlinesm.yStart & linesn.yStartlinesm.yStart)/ MessageBox(hwnd,error3,error3,MB_OK);x=linesm.xStart;drawb.x=x;drawb.y=k;b+;drawb.x=x;drawb.y=k;b+;else/ MessageBox(hwnd,error4,error4,MB_OK);x=linesm.xStart;flag=0;for(h=0;hb;h+)if(x=drawh.x & k=drawh.y)flag=1;break;if(flag!=1)drawb.x=x;drawb.y=k;b+;else if(linesm.yEnd=k)for(n=0;nlinesm.yEnd & linesn.yEndlinesm.yEnd) | (linesm.yStartlinesm.yEnd & linesn.yEndlinesm.yEnd)/ MessageBox(hwnd,error,error,MB_OK);x=linesm.xEnd;drawb.x=x;drawb.y=k;b+;drawb.x=x;drawb.y=k;b+;elsex=linesm.xEnd;flag=0;for(h=0;hlinesm.yEnd & linesn.yStartlinesm.yEnd) | (linesm.yStartlinesm.yEnd & linesn.yStartlinesm.yEnd)x=linesm.xEnd;drawb.x=x;drawb.y=k;b+;drawb.x=x;drawb.y=k;b+;elsex=linesm.xEnd;flag=0;for(h=0;hlinesm.yEnd)x1=linesm.xEnd;y1=linesm.yEnd;x2=linesm.xStart;y2=linesm.yStart;else if(linesm.yStartlinesm.yEnd)x1=linesm.xStart;y1=linesm.yStart;x2=linesm.xEnd;y2=linesm.yEnd;x=x2+(x1-x2)*(y2-k)/(y2-y1);drawb.x=x;drawb.y=k;b+;/check complete,then draw them/sorting first!for(h=0;hb;h+)for(m=h+1;mdrawm.x)x=drawh.x;drawh.x=drawm.x;drawm.x=x;x=drawh.y;drawh.y=drawm.y;drawm.y=x;hdc=GetDC(hwnd); /real filling for(h=0;hb;h+=2) MoveToEx(hdc,drawh.x,drawh.y,NULL);LineTo(hdc,drawh+1.x,drawh+1.y);ReleaseDC(hwnd,hdc);for(h=0;hb;h+)draw_refreshl.x=drawh.x;dr