phaser/src/math/Rotate.js
2018-04-24 16:22:05 +10:00

29 lines
881 B
JavaScript

/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2018 Photon Storm Ltd.
* @license {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
*/
/**
* Rotate a given point by a given angle around the origin (0, 0), in an anti-clockwise direction.
*
* @function Phaser.Math.Rotate
* @since 3.0.0
*
* @param {(Phaser.Geom.Point|object)} point - The point to be rotated.
* @param {number} angle - The angle to be rotated by in an anticlockwise direction.
*
* @return {Phaser.Geom.Point} The given point, rotated by the given angle in an anticlockwise direction.
*/
var Rotate = function (point, angle)
{
var x = point.x;
var y = point.y;
point.x = (x * Math.cos(angle)) - (y * Math.sin(angle));
point.y = (x * Math.sin(angle)) + (y * Math.cos(angle));
return point;
};
module.exports = Rotate;