计算机图形学代码_CS法直线段裁剪.doc

这段代码主要是用CS法对一个直线段进行裁剪。运行在VC环境下。typedef structfloat x,y;Point;typedef structunsigned all;unsigned left,right,top,bottom;OutCode;void CompOutCode(Point p,RECT* rect,OutCode *outCode)outCode-all=0;outCode-top=outCode-bottom=0;if(p.y(float)rect-bottom)outCode-top=1;outCode-all+=1;else if(p.ytop)outCode-bottom=1;outCode-all+=1;outCode-left=outCode-right=0;if(p.x(float)rect-right)outCode-right=1;outCode-all+=1;else if(p.xleft)outCode-left=1;outCode-all+=1;void Cohen_SutherlandLineClip(Point p0,Point p1,RECT *rect,CDC* pDC)bool accept=false,done=false;OutCode outCode0,outCode1;OutCode *outCodeOut;Point p;CompOutCode(p0,rect,&outCode0);CompOutCode(p1,rect,&outCode1);doif(!outCode0.all&!outCode1.all)accept=done=true;else if(outCode0.all&outCode1.all)!=0)done=true;elseif(outCode0.all)outCodeOut=&outCode0;elseoutCodeOut=&outCode1;if(outCodeOut-left)p.y=p0.y+(p1.y-p0.y)*(rect-left-p0.x)/(p1.x-p0.x);p.x=(float)rect-left;else if(outCodeOut-top)p.x=p0.x+(p1.x-p0.x)*(rect-top-p0.y)/(p1.y-p0.y);p.y=(float)rect-top;else if(outCodeOut-right)p.y=p0.y+(p1.y-p0.y)*(rect-right-p0.x)/(p1.x-p0.x);p.x=(float)rect-right;else if(outCodeOut-bottom)p.x=p0.x+(p1.x-p0.x)*(rect-bottom-p0.y)/(p1.y-p0.y);p.y=(float)rect-bottom;if(outCodeOut-all=outCode0.all)p0.x=p.x;p0.y=p.y;CompOutCode(p0,rect,&outCode0);elsep1.x=p.x;p1.y=p.y;CompOutCode(p1,rect,&outCode1);while(!done);if(accept)pDC-MoveTo(int)p0.x,(int)p0.y);pDC-LineTo(int)p1.x,(int)p1.y);void CCohen_SutherlandView:OnDraw(CDC* pDC)CCohen_SutherlandDoc* pDoc = GetDocument();ASSERT_VALID(pDoc);/ TODO: add draw code for native data hereRECT rect=50,100,150,200;pDC-Rectangle(&rect);Poi