phaser/src/math/RotateAroundDistance.js
2020-04-27 16:13:17 +01:00

35 lines
1.2 KiB
JavaScript

/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2020 Photon Storm Ltd.
* @license {@link https://opensource.org/licenses/MIT|MIT License}
*/
/**
* Rotate a `point` around `x` and `y` by the given `angle` and `distance`.
*
* In polar notation, this maps a point from (r, t) to (distance, t + angle), vs. the origin (x, y).
*
* @function Phaser.Math.RotateAroundDistance
* @since 3.0.0
*
* @generic {Phaser.Types.Math.Vector2Like} T - [point,$return]
*
* @param {(Phaser.Geom.Point|object)} point - The point to be rotated.
* @param {number} x - The horizontal coordinate to rotate around.
* @param {number} y - The vertical coordinate to rotate around.
* @param {number} angle - The angle of rotation in radians.
* @param {number} distance - The distance from (x, y) to place the point at.
*
* @return {Phaser.Types.Math.Vector2Like} The given point.
*/
var RotateAroundDistance = function (point, x, y, angle, distance)
{
var t = angle + Math.atan2(point.y - y, point.x - x);
point.x = x + (distance * Math.cos(t));
point.y = y + (distance * Math.sin(t));
return point;
};
module.exports = RotateAroundDistance;