图形学填充实验.docx

#include gl/glut.h#include windows.hconst int POINTNUM=4; //多边形点数./******定义结构体用于活性边表AET和新边表NET***********************************/ typedef struct XET { float x; float dx,ymax; XET* next; }AET,NET;/******定义点结构体point******************************************************/ struct point { float x; float y; } polypoint[POINTNUM]={250,50,550,150,550,400,250,250};//多边形顶点 void PolyScan(){/******计算最高点的y坐标(扫描到此结束)****************************************/ int MaxY=0; int i; for(i=0;iPOINTNUM;i++) if(polypoint[i].yMaxY) MaxY=polypoint[i].y;/*******初始化AET表***********************************************************/ AET *pAET=new AET; pAET-next=NULL;/******初始化NET表************************************************************/ NET *pNET[1024]; for(i=0;i=MaxY;i++) { pNET[i]=new NET; pNET[i]-next=NULL; } glClear(GL_COLOR_BUFFER_BIT); //赋值的窗口显示. glColor3f(0.0,0.0,0.0); //设置直线的颜色红色 glBegin(GL_POINTS);/******扫描并建立NET表*********************************************************/ for(i=0;i=MaxY;i++) { for(int j=0;jPOINTNUM;j++) if(polypoint[j].y==i) { //一个点跟前面的一个点形成一条线段，跟后面的点也形成线段 if(polypoint[(j-1+POINTNUM)%POINTNUM].ypolypoint[j].y) { NET *p=new NET; p-x=polypoint[j].x; p-ymax=polypoint[(j-1+POINTNUM)%POINTNUM].y; p-dx=(polypoint[(j-1+POINTNUM)%POINTNUM].x-polypoint[j].x)/(polypoint[(j-1+POINTNUM)%POINTNUM].y-polypoint[j].y); p-next=pNET[i]-next; pNET[i]-next=p; } if(polypoint[(j+1+POINTNUM)%POINTNUM].ypolypoint[j].y) { NET *p=new NET; p-x=polypoint[j].x; p-ymax=polypoint[(j+1+POINTNUM)%POINTNUM].y; p-dx=(polypoint[(j+1+POINTNUM)%POINTNUM].x-polypoint[j].x)/(polypoint[(j+1+POINTNUM)%POINTNUM].y-polypoint[j].y); p-next=pNET[i]-next; pNET[i]-next=p; } } }/******建立并更新活性边表AET*****************************************************/for(i=0;i=MaxY;i++) { //计算新的交点x,更新AET NET *p=pAET-next; while(p) { p-x=p-x + p-dx; p=p-next; } //更新后新AET先