BRESENHA.CPP

#include<iostream.h>
#include<graphics.h>
#include<conio.h>
#include<conio.h>
#include<math.h>
void Bresenham(int x1,int y1,int x2,int y2,int col)
 {
  int dx,dy,p;
  dx=abs(x2-x1);
  dy=abs(y2-y1);
  int x=x1;
  int y=y1;
  if(dx>=dy)
   {
    p=2*dy-dx;
    do{
     putpixel(x,y,col);
     if(p>0)
      {
      if(y2>y1)
      {
       y++;
      }
      else
       {
	y--;
       }
       p=p+2*dy-2*dx;
      }
     else
      {
       p=p+2*dy;
      }
     if(x1<x2)
     {
      x++;
     }
     else
      {
       x--;
      }
    }while(x!=x2);
    putpixel(x,y,col);
   }
  else
   {
    p=2*dx-dy;
    do{
     putpixel(x,y,col);
     if(p>0)
      {
       if(x1<x2)
       {
	x++;
       }
      else
       {
	x--;
       }
       p=p+2*dx-2*dy;
      }
     else
      {
       p=p+2*dx;
      }
     if(y1<y2)
     {
     y++;
     }
    else
     {
      y--;
     }
    }while(y!=y2);
    putpixel(x,y,col);
   }
 }