### Line Clipping - Cohen Sutherland Line Clipping Algorithm - Graphics.h in Ubuntu - C++ Program

Line Clipping
Cohen Sutherland Line Clipping Algorithm
Graphics & Multimedia Lab - C++ Program

Program:

```#include<iostream>
#include<graphics.h>
using namespace std;

const int TOP=8,BOTTOM=4,RIGHT=2,LEFT=1;

typedef int outcode;

outcode compute(int x, int y , int xmax, int ymax, int xmin, int ymin)
{
outcode oc=0;
if(x<xmin)
oc|=LEFT;
else if(x>xmax)
oc|=RIGHT;
if(y>ymax)
oc|=TOP;
else if(y<ymin)
oc|=BOTTOM;

return oc;

}

void coh(int x1,int y1,int x2,int y2, int xmin,int ymin, int xmax, int ymax)
{
bool accept = false, done=false;double m;
outcode o1,o2,ot;
o1=compute(x1,y1,xmax,ymax,xmin,ymin);
o2=compute(x2,y2,xmax,ymax,xmin,ymin);
do{

if(!(o1 | o2))
{
done=true;
accept=true;
}
else if(o1&o2)
{
done=true;

}
else
{
int x,y;
ot=o1?o1:o2;
if(ot & TOP)
{
y=ymax;
x = x1 + (x2-x1)*(ymax-y1)/(y2-y1);
}
else if(ot & BOTTOM)
{
y=ymin;
x = x1 + (x2 - x1) * (ymin - y1) / (y2 - y1);
}
else if(ot & RIGHT)
{
x=xmax;
y = y1 + (y2 - y1) * (xmax - x1) / (x2 - x1);
}
else if(ot & LEFT)
{
x=xmin;
y = y1 + (y2 - y1) * (xmin - x1) / (x2 - x1);

}
if(ot==o1)
{

x1=x;
y1=y;
o1=compute(x1,y1,xmax,ymax,xmin,ymin);
}
else
{

x2=x;
y2=y;
o2=compute(x2,y2,xmax,ymax,xmin,ymin);
}

}
}while(done==false);

if(accept==true)
{
line(x1,y1,x2,y2);
}

}

int main()
{
int gd=DETECT,gm,x,y,j,i;
initgraph(&gd,&gm,NULL);

outtextxy(150,15, "Cohen Sutherland");

int xmx=200,ymx=200,xmn=100,ymn=100;

int ax1=50,ay1=75,bx1=50,by1=325;
int ax2=150,ay2=75,bx2=150,by2=325;
int ax3=250,ay3=75,bx3=250,by3=325;
int ax4=50,ay4=75,bx4=250,by4=75;
int ax5=50,ay5=175,bx5=250,by5=175;
int ax6=50,ay6=275,bx6=250,by6=275;
int ax7=50,ay7=75,bx7=275,by7=275;
int ax8=250,ay8=75,bx8=75,by8=275;

line(ax1,ay1,bx1,by1);
line(ax2,ay2,bx2,by2);
line(ax3,ay3,bx3,by3);
line(ax4,ay4,bx4,by4);
line(ax5,ay5,bx5,by5);
line(ax6,ay6,bx6,by6);
line(ax7,ay7,bx7,by7);
line(ax8,ay8,bx8,by8);
setcolor(4);
rectangle(xmn,ymn,xmx,ymx);
delay(1000);

cleardevice();

setcolor(4);
rectangle(xmn,ymn,xmx,ymx);

setcolor(15);
coh(ax1,ay1,bx1,by1,xmn,ymn,xmx,ymx);
coh(ax2,ay2,bx2,by2,xmn,ymn,xmx,ymx);
coh(ax3,ay3,bx3,by3,xmn,ymn,xmx,ymx);
coh(ax4,ay4,bx4,by4,xmn,ymn,xmx,ymx);
coh(ax5,ay5,bx5,by5,xmn,ymn,xmx,ymx);
coh(ax6,ay6,bx6,by6,xmn,ymn,xmx,ymx);
coh(ax7,ay7,bx7,by7,xmn,ymn,xmx,ymx);
coh(ax8,ay8,bx8,by8,xmn,ymn,xmx,ymx);
delay(1000);

getch();
closegraph();
return 0;
}```

Output: