计算机图形学2

计算机图形学2中国地质大学（武汉）课题：计算机图形学班级：191113姓名：杨耀鹏voidbuildEdgeList(intcnt,dePt*pts,Edge*edges[]){Edge*edge;dePtv1,v2;inti,yPrev=pts[cnt-2].y;v1.x=pts[cnt-1].x;v1.y=pts[cnt-1].y;for(i=0;i<cnt;i++){v2=pts[i];if(v1.y!=v2.y){edge=(Edge*)malloc(sizeof(Edge));if(v1.y<v2.y)makeEdgeRec(v1,v2,yNext(i,cnt,pts),edge,edges);elsemakeEdgeRec(v2,v1,yPrev,edge,edges);}yPrev=v1.y;v1=v2;}}voidbuildActiveList(intscan,Edge*active,Edge*edges[]){Edge*p,*q;p=edges[scan]->next;while(p){q=p->next;insertEdge(active,p);p=q;}}voidfillScan(intscan,Edge*active){Edge*p1,*p2;inti;p1=active->next;while(p1){p2=p1->next;for(i=p1->xIntersect;i<p2->xIntersect;i++)fill((int)i,scan,3);p1=p2->next;}}voiddeleteAfter(Edge*q){Edge*p=q->next;q->next=p->next;free(p);}voidupdateActiveList(intscan,Edge*active){Edge*q=active,*p=active->next;while(p)if(scan>=p->yUpper){p=p->next;deleteAfter(q);}else{p->xIntersect=p->xIntersect+p->dxPerScan;q=p;p=p->next;}}voidresortActiveList(Edge*active){Edge*q,*p=active->next;active->next=NULL;while(p){q=p->next;insertEdge(active,p);p=q;}}voidscanFill(intcnt,dePt*pts){Edge*edges[1024],*active;inti,scan;for(i=0;i<1024;i++){edges[i]=(Edge*)malloc(sizeof(Edge));edges[i]->next=NULL;}buildEdgeList(cnt,pts,edges);active=(Edge*)malloc(sizeof(Edge));active->next=NULL;for(scan=0;scan<1024;scan++){buildActiveList(scan,active,edges);if(active->next){fillScan(scan,active);updateActiveList(scan,active);resortActiveList(active);}}}voidChangeSize(GLsizeiw,GLsizeih){GLfloatnRange=400.0f;if(h==0)h=1;glViewport(0,0,w,h);glMatrixMode(GL_PROJECTION);glLoadIdentity();if(w<=h)glOrtho(-nRange,nRange,-nRange*h/w,nRange*h/w,-nRange,nRange);elseglOrtho(-nRange*h/w,nRange*h/w,-nRange,nRange,-nRange,nRange);glMatrixMode(GL_MODELVIEW);glLoadIdentity();}voidDisplay(void){intn,x,y,i;cout<<"请输入多边形顶点数："<<endl;cin>>n;dePt*t=newdePt[n];for(i=0;i<n;i++){ cout<<"请输入第"<<i+1<<"个顶点坐标"<<endl;cin>>x>>y; t[i].x=x; t[i].y=y; glVertex2i(t[i].x,t[i].y);} glEnd();glFlush();scanFill(n,t);glFlush(); glutPostRedisplay();}voidInitial(void){ glClearColor(2.0f,2.0f,2.0f,2.0f); glMatrixMode(GL_PROJECTION);//指定设置投影参数 gluOrtho2D(-100.0,200.0,-100.0,150.0);//设置投影参数 }voidmain(intargc,char*argv[]){ glutInit(&argc,argv); glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);//初始化窗口的显示模式 glutInitWindowSize(400,300);//设置窗口的尺寸 glutInitWindowPosition(100,120);//设置窗口的位置 glutCreateWindow("多边形的扫描转换与填充");//设置一个名为多边形的扫描转换与填充的窗口 glutDisplayFunc(Display);//设置当前窗口的显示调用函数