用VC++6.0实现的扫描线填充,裁剪算法及画线方法 CPenpen(PS_SOLID,1,fillcolor);//设置扫描线所用笔的属性 CPen*old=pDC->SelectObject(&pen); intj,k,s=0; intp[9];//每根扫描线交点 intpmin=1000; intpmax=0; for(inti=0;i<inLength;i++)//建立边表 { edge[i].dx=(float)(inVertexArray[i+1].x-inVertexArray[i].x)/(inVertexArray[i+1].y-inVertexArray[i].y); edge[i].num=i; if(inVertexArray[i].y<=inVertexArray[i+1].y) { edge[i].ymin=inVertexArray[i].y; edge[i].ymax=inVertexArray[i+1].y; edge[i].xmin=(float)inVertexArray[i].x; edge[i].xmax=(float)inVertexArray[i+1].x; } else{ edge[i].ymin=inVertexArray[i+1].y; edge[i].ymax=inVertexArray[i].y; edge[i].xmax=(float)inVertexArray[i].x; edge[i].xmin=(float)inVertexArray[i+1].x; } } //求多边形的最大最小值 for(intm=1;m<inLength;m++) { for(intn=0;n<inLength-m;n++) { if(pmaxinVertexArray[n].y) pmin=inVertexArray[n].y; } } for(intr=1;r<inLength;r++) //边表edge排序 { for(intq=0;q<inLength-r;q++) { if(edge[q].yminpmin;scan--)//扫描线遵守'“上开下闭”的原则 { intb=0; k=s; for(j=k;j=edge[j].ymin)&&(scan<=edge[j].ymax))//判断扫描线与线段是否相交于顶点 { intpreNum=edge[j].num; intnextNum=edge[j].num+1; if(preNum==0) preNum=inLength-1; else preNum=preNum-1; if(nextNum==inLength) nextNum=0; if(scan==edge[j].ymax)//位于下顶点时,根据相临点的位置决定取几个点 { if(inVertexArray[nextNum].y<edge[j].ymax) { b++; p[b]=(int)edge[j].xmax; } if(inVertexArray[preNum].yedge[j].ymin)&&(scan<edge[j].
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