phaser/src/geom/triangle/Area.js

A fast, free and fun HTML5 Game Framework for Desktop and Mobile web browsers.

/**
 * @author       Richard Davey <rich@photonstorm.com>
 * @copyright    2018 Photon Storm Ltd.
 * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
 */

// The 2D area of a triangle. The area value is always non-negative.

/**
 * [description]
 *
 * @function Phaser.Geom.Triangle.Area
 * @since 3.0.0
 *
 * @param {Phaser.Geom.Triangle} triangle - [description]
 *
 * @return {number} [description]
 */
var Area = function (triangle)
{
    var x1 = triangle.x1;
    var y1 = triangle.y1;

    var x2 = triangle.x2;
    var y2 = triangle.y2;

    var x3 = triangle.x3;
    var y3 = triangle.y3;

    return Math.abs(((x3 - x1) * (y2 - y1) - (x2 - x1) * (y3 - y1)) / 2);
};

module.exports = Area;