Bresenham-line.cpp

#include<stdio.h>
#include<conio.h>
#include<graphics.h>
void drawline(int x0, int y0, int x1, int y1){

int dx, dy, p, x, y; 
dx=x1-x0;
dy=y1-y0; 
x=x0;
y=y0;
p=2*dy-dx; 

while(x<x1) {
if(p>=0) {
putpixel(x,y,7);
y=y+1;
p=p+2*dy-2*dx; }
else {
putpixel(x,y,7);
p=p+2*dy; }
x=x+1; }
}

main()
{
int gdriver=DETECT, gmode, error, x0, y0, x1, y1;
initgraph(&gdriver, &gmode, "c:\\turboc3\\bgi"); 
printf("Enter co-ordinates of first point: ");
scanf("%d%d", &x0, &y0); 
printf("Enter co-ordinates of second point: ");
scanf("%d%d", &x1, &y1);
drawline(x0, y0, x1, y1);
getch();
}