phaser/v3/src/geom/circle/Random.js

27 lines
927 B
JavaScript

var Point = require('../point/Point');
/**
* Returns a uniformly distributed random point from anywhere within this Circle.
*
* @method Phaser.Circle#random
* @param {Phaser.Point|object} [out] - A Phaser.Point, or any object with public x/y properties, that the values will be set in.
* If no object is provided a new Phaser.Point object will be created. In high performance areas avoid this by re-using an existing object.
* @return {Phaser.Point} An object containing the random point in its `x` and `y` properties.
*/
var Random = function (circle, out)
{
if (out === undefined) { out = new Point(); }
var t = 2 * Math.PI * Math.random();
var u = Math.random() + Math.random();
var r = (u > 1) ? 2 - u : u;
var x = r * Math.cos(t);
var y = r * Math.sin(t);
out.x = circle.x + (x * circle.radius);
out.y = circle.y + (y * circle.radius);
return out;
};
module.exports = Random;