BRESENHAM’S LINE DRAWING ALGORITHM



#include "stdio.h"
#include "conio.h"
#include "math.h"
#include "graphics.h"
main()
{
int gd=DETECT,gm;
int xa,xb,ya,yb;
int dx,dy,x,y,xend,p;
initgraph(&gd,&gm,"c:\\tc\\bgi");
printf("Enter The Two Left Endpoints(xa,ya):\n");
scanf("%d%d",&xa,&ya);
printf("Enter The Two Right Endpoints(xb,yb):\n");
scanf("%d%d",&xb,&yb);
dx=abs(xa-xb);
dy=abs(ya-yb);
p=2*dy-dx;
if(xa>xb)
{
x=xb;
y=yb;
xend=xa;
}
else
{

x=xa;
y=ya;
xend=xb;
}
      putpixel(x,y,6);
    while(x<xend)
      {
      x=x+1;
      if(p<0)
      {
      p=p+2*dy;
      }
      else
      {
      y=y+1;
      p=p+2*(dy-dx);
      }
      putpixel(x,y,6);
      }
   getch();
   return(0);
}

OUTPUT

Enter The Two Left Endpoints(xa,ya): 234 124

Enter The Two Right Endpoints(xb,yb): 578 321