(function (exports) {

'use strict';

/**

* Bresenham's line drawing algorithm.

* It has complexity O(n)

* @param {number} x1 The first coordinate of the beginning of the line

* @param {number} y1 The second coordinate of the beginning of the line

* @param {number} x2 The first coordinate of the end of the line

* @param {number} y2 The second coordinate of the end of the line

* @param {function} draw Optional custom drawing function.

*/

function drawLine(x1, y1, x2, y2, draw) {

drawPoint = draw || drawPoint;

var dx = Math.abs(x2 - x1);

var dy = Math.abs(y2 - y1);

var cx = (x1 < x2) ? 1 : -1;

var cy = (y1 < y2) ? 1 : -1;

var error = dx - dy;

var doubledError;

while (x1 !== x2 || y1 !== y2) {

drawPoint(x1, y1);

doubledError = error + error;

if (doubledError > -dy) {

error -= dy;

x1 += cx;

}

if (doubledError < dx) {

error += dx;

y1 += cy;

}

}

}

/**

* Draws (prints) the given coordinates

* @param {number} x The first coordinate of the point

* @param {number} y The second coordinate of the point

*/

function drawPoint(x, y) {

console.log(x, y);

}

exports.drawLine = drawLine;

}(typeof exports === 'undefined' ? window : exports));