Bresenham line drawing algorithm

Bresenham line drawing algorithm

My code for Bresenham line drawing algorithm which will help you to learn how the algorithm actually works. 

Source code:

#include<iostream.h>

#include<conio.h>

#include<graphics.h>

void bresenham(int x1,int y1,int x2,int y2);

void main()

{int gd=DETECT,gm;

int x1,x2,y1,y2;

initgraph( &gd, &gm,"C:\\TC\\BGI");

cleardevice();

cout<<"Bresenham Line generation Algorithm";

cout<<"\n enter the starting co-ordinates for drawing line";

cin>>x1>>y1;

cout<<"\n enter the ending co-ordinates";

cin>>x2>>y2;

bresenham(x1,y1,x2,y2);

cout<<"\n Thank you";

getch();

closegraph();

}

void bresenham(int x1,int y1,int x2,int y2)

{int x,y,dx,dy,e,i;

if(x1>x2)

{bresenham(x2,y2,x1,y1);

return;}

dx=x2-x1;

dy=y2-y1;

e=2*dy-dx;

x=x1;

y=y1;

putpixel(x,y,WHITE);

cout<<"("<<x<<","<<y<<")";

getch();

for(i=1;i<=dx;i++)

{while(e>=0)

{y=y+1;

e=e-2*dx;}

x=x+1;

e=e+2*dy;

putpixel(x,y,WHITE);

cout<<"("<<x<<","<<y<<")";

getch();

}

}

OUTPUT: