phaser/src/geom/circle/Random.js

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/**
* @author Richard Davey <rich@photonstorm.com>
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* @copyright 2020 Photon Storm Ltd.
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* @license {@link https://opensource.org/licenses/MIT|MIT License}
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*/
var Point = require('../point/Point');
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/**
* Returns a uniformly distributed random point from anywhere within the given Circle.
*
* @function Phaser.Geom.Circle.Random
* @since 3.0.0
*
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* @generic {Phaser.Geom.Point} O - [out,$return]
*
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* @param {Phaser.Geom.Circle} circle - The Circle to get a random point from.
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* @param {(Phaser.Geom.Point|object)} [out] - A Point or point-like object to set the random `x` and `y` values in.
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*
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* @return {(Phaser.Geom.Point|object)} A Point object with the random values set in the `x` and `y` properties.
*/
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var Random = function (circle, out)
{
if (out === undefined) { out = new Point(); }
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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;