text: /**
   * @author       Richard Davey <rich@photonstorm.com>
   * @copyright    2018 Photon Storm Ltd.
   * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
   */
  
  var Centroid = require('./Centroid');
  var Offset = require('./Offset');
  
  /**
   * @callback CenterFunction
   *
   * @param {Phaser.Geom.Triangle} triangle - The Triangle to return the center coordinates of.
   *
   * @return {Phaser.Math.Vector2} The center point of the Triangle according to the function.
   */
  
  /**
   * Positions the Triangle so that it is centered on the given coordinates.
   *
   * @function Phaser.Geom.Triangle.CenterOn
   * @since 3.0.0
   *
   * @generic {Phaser.Geom.Triangle} O - [triangle,$return]
   *
   * @param {Phaser.Geom.Triangle} triangle - The triangle to be positioned.
   * @param {number} x - The horizontal coordinate to center on.
   * @param {number} y - The vertical coordinate to center on.
   * @param {CenterFunction} [centerFunc] - The function used to center the triangle. Defaults to Centroid centering.
   *
   * @return {Phaser.Geom.Triangle} The Triangle that was centered.
   */
  var CenterOn = function (triangle, x, y, centerFunc)
  {
      if (centerFunc === undefined) { centerFunc = Centroid; }
  
      //  Get the center of the triangle
      var center = centerFunc(triangle);
  
      //  Difference
      var diffX = x - center.x;
      var diffY = y - center.y;
  
      return Offset(triangle, diffX, diffY);
  };
  
  module.exports = CenterOn;
  