phaser/src/geom/polygon/Perimeter.js
2020-01-15 12:07:09 +00:00

42 lines
960 B
JavaScript

/**
* @author Richard Davey <rich@photonstorm.com>
* @copyright 2020 Photon Storm Ltd.
* @license {@link https://opensource.org/licenses/MIT|MIT License}
*/
var Length = require('../line/Length');
var Line = require('../line/Line');
/**
* Returns the perimeter of the given Polygon.
*
* @function Phaser.Geom.Polygon.Perimeter
* @since 3.12.0
*
* @param {Phaser.Geom.Polygon} polygon - The Polygon to get the perimeter of.
*
* @return {number} The perimeter of the Polygon.
*/
var Perimeter = function (polygon)
{
var points = polygon.points;
var perimeter = 0;
for (var i = 0; i < points.length; i++)
{
var pointA = points[i];
var pointB = points[(i + 1) % points.length];
var line = new Line(
pointA.x,
pointA.y,
pointB.x,
pointB.y
);
perimeter += Length(line);
}
return perimeter;
};
module.exports = Perimeter;