VC++ 6.0编写计算机图形学中的种子填充算法，想用递归的八向连通域，求助！0

填充函数代码如下：

void CComputerGraphicsView::PolygonFill2()//区域填充函数

{

CClientDC dc(this);

COLORREF FillColor,BoundaryColor,PixelColor;//填充色，边界色，当前点像素色

BoundaryColor=RGB(0,0,0);//边界色为黑色

FillColor=RGB(0,0,255);//填充色为蓝色

Head=new Stack_node();//建立堆栈结点

Head->PixelPoint=Seed;//种子结点入栈

Head->Next=NULL;

while(Head!=NULL)//如果栈不为空

{

Stack_node *PopPoint;

PopPoint=Pop();

if(PopPoint==NULL)

{

dc.TextOut(10,10,"填充完毕");

dc.DeleteDC();

return;

}

Last=Base;

dc.SetPixel(PopPoint->PixelPoint,FillColor);//画蓝色种子

//搜索出栈结点的左方像素

PointLeft.x=PopPoint->PixelPoint.x-1;

PointLeft.y=PopPoint->PixelPoint.y;

PixelColor=dc.GetPixel(PointLeft.x,PointLeft.y);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

//不是边界色并且未置成填充色

Push(PointLeft);//左方像素入栈

//搜索出栈结点的上方像素

PointTop.x=PopPoint->PixelPoint.x;

PointTop.y=PopPoint->PixelPoint.y+1;

PixelColor=dc.GetPixel(PointTop);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointTop); //上方像素入栈

//搜索出栈结点的右方像素

PointRight.x=PopPoint->PixelPoint.x+1;

PointRight.y=PopPoint->PixelPoint.y;

PixelColor=dc.GetPixel(PointRight);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointRight);//右方像素入栈

//搜索出栈结点的下方像素

PointBottom.x=PopPoint->PixelPoint.x;

PointBottom.y=PopPoint->PixelPoint.y-1;

PixelColor=dc.GetPixel(PointBottom);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointBottom);//下方像素入栈

PointLeftTop.x=PopPoint->PixelPoint.x-1;

PointLeftTop.y=PopPoint->PixelPoint.y+1;

PixelColor=dc.GetPixel(PointLeftTop);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointLeftTop); //左上方像素入栈

PointRightTop.x=PopPoint->PixelPoint.x+1;

PointRightTop.y=PopPoint->PixelPoint.y+1;

PixelColor=dc.GetPixel(PointRightTop);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointRightTop); //右上方像素入栈

PointLeftBottom.x=PopPoint->PixelPoint.x-1;

PointLeftBottom.y=PopPoint->PixelPoint.y-1;

PixelColor=dc.GetPixel(PointLeftBottom);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointLeftBottom); //左下方像素入栈

PointRightBottom.x=PopPoint->PixelPoint.x+1;

PointRightBottom.y=PopPoint->PixelPoint.y-1;

PixelColor=dc.GetPixel(PointRightBottom);

if(PixelColor!=BoundaryColor && PixelColor!=FillColor)

Push(PointRightBottom); //右下方像素入栈

}

}

编译运行无错，但是扫描结果会超出多边形区域并死循环，这是为什么？如果把左上左下右上右下四个搜索方向去掉改成四向搜索却可行！