实验4：直线或多边形裁剪

计算机图形学实验报告实验4：直线或多边形裁剪实验目的：实现标准矩形窗口的裁剪，窗口由键盘输入或鼠标确定，直线/多边形都是任意的。裁剪后的图形要准确，不能多或者少点。实验内容及要求：对于直线/多边形的裁剪实验，要求实现标准矩形窗口的裁剪，窗口由键盘输入或鼠标确定，直线/多边形都是任意的。裁剪后的图形要准确，不能多或者少点。对于上述两个实验都要求掌握各自算法的基本原理和算法设计，画出算法实现的程序流程图，使用C或者VC++实现算法，并演示。实验原理：实验代码：#include<stdlib.h>#include<stdio.h>#include<conio.h>#include<graphics.h>typedefstruct{floatx,y;}Point;voidinitgraphics(void);voidCode(PointFrameLT,PointFrameRB,PointP,unsignedchar*Flag);voidClipping(PointFrameLT,PointFrameRB,PointLineSP,PointLineEP);voidmain(void){PointFrameLT,FrameRB;PointP[3];initgraphics();setcolor(RED);FrameLT.x=200;FrameLT.y=100;FrameRB.x=460;FrameRB.y=360;rectangle((int)FrameLT.x,(int)FrameLT.y,(int)FrameRB.x,(int)FrameRB.y);P[0].x=330;P[0].y=80;P[1].x=150;P[1].y=300;P[2].x=510;P[2].y=200;line((int)P[0].x,(int)P[0].y,(int)P[1].x,(int)P[1].y);line((int)P[0].x,(int)P[0].y,(int)P[2].x,(int)P[2].y);line((int)P[1].x,(int)P[1].y,(int)P[2].x,(int)P[2].y);getch();cleardevice();rectangle((int)FrameLT.x,(int)FrameLT.y,(int)FrameRB.x,(int)FrameRB.y);Clipping(FrameLT,FrameRB,P[0],P[1]);Clipping(FrameLT,FrameRB,P[0],P[2]);Clipping(FrameLT,FrameRB,P[1],P[2]);getch();closegraph();}voidinitgraphics(void){intdriver=VGA,mode=VGAHI;interrcode;initgraph(&driver,&mode,"");if((errcode=graphresult())!=0){printf("Graphicserror:%s\n",grapherrormsg(errcode));exit(1);}}voidCode(PointFrameLT,PointFrameRB,PointP,unsignedchar*Flag){unsignedcharflag=0;if(P.x<FrameLT.x)flag+=1;if(P.x>FrameRB.x)flag+=2;if(P.y>FrameRB.y)flag+=4;if(P.y<FrameLT.y)flag+=8;(*Flag)=flag;}voidClipping(PointFrameLT,PointFrameRB,PointLineSP,PointLineEP){unsignedcharflagSP,flagEP,flagAND,flagOR;doublek=(LineEP.y-LineSP.y)/(LineEP.x-LineSP.x);Code(FrameLT,FrameRB,LineSP,&flagSP);Code(FrameLT,FrameRB,LineEP,&flagEP);flagAND=flagSP&flagEP;if(flagAND!=0)return;while(flagSP!=0||flagEP!=0){flagOR=flagSP|flagEP;if((flagOR&0x01)==1){if((flagSP&0x01)==1){LineSP.y=LineSP.y+k*(FrameLT.x-LineSP.x);LineSP.x=FrameLT.x;Code(FrameLT,FrameRB,LineSP,&flagSP);}else{LineEP.y=LineEP.y+k*(FrameLT.x-LineEP.x);LineEP.x=FrameLT.x;Code(FrameLT,FrameRB,LineEP,&flagEP);}}if((flagOR&0x02)==2){if((flagSP&0x02)==2){LineSP.y=LineSP.y+k*(FrameRB.x-LineSP.x);LineSP.x=FrameRB.x;Code(FrameLT,FrameRB,LineSP,&flagSP);}else{LineEP.y=LineEP.y+k*(FrameRB.x-LineEP.x);LineEP.x=FrameRB.x;Code(FrameLT,FrameRB,LineEP,&flagEP);}}if((flagOR&0x04)==4){if((flagSP&0x04)==4){LineSP.x=LineSP.x+(FrameRB.y-LineSP.y)/k;LineSP.y=FrameRB.y;Code(FrameLT,FrameRB,LineSP,&flagSP);}else{LineEP.x=LineEP.x+(FrameRB.y-LineEP.y)/k;LineEP.y=FrameRB.y;Code(FrameLT,FrameRB,LineEP,&flagEP);}}if((flagOR&0x08)==8){if((flagSP&0x08)==8){LineSP.x=LineSP.x+(FrameLT.y-LineSP.y)/k;LineSP.y=FrameLT.y;Code(FrameLT,FrameRB,LineSP,&flagSP);}else{LineEP.x=LineEP.x+(FrameLT.y-LineEP.y)/k;LineEP.y=FrameLT.y;Code(FrameLT,FrameRB,LineEP,&flagEP);}flagAND=flagSP&flagEP;if(flagAND!=0)return;}line((int)LineSP.x,(int)LineSP.y,(int)