Phaser Source: src/physics/p2/FixtureList.js

# Source: src/physics/p2/FixtureList.js

    /* jshint noarg: false */

    /**
    * @author       Georgios Kaleadis https://github.com/georgiee
    * @author       Richard Davey <rich@photonstorm.com>
    * @copyright    2016 Photon Storm Ltd.
    * @license      {@link https://github.com/photonstorm/phaser/blob/master/license.txt|MIT License}
    */

    /**
    * Allow to access a list of created fixture (coming from Body#addPhaserPolygon)
    * which itself parse the input from PhysicsEditor with the custom phaser exporter.
    * You can access fixtures of a Body by a group index or even by providing a fixture Key.

    * You can set the fixture key and also the group index for a fixture in PhysicsEditor.
    * This gives you the power to create a complex body built of many fixtures and modify them
    * during runtime (to remove parts, set masks, categories & sensor properties)
    *
    * @class Phaser.Physics.P2.FixtureList
    * @constructor
    * @param {Array} list - A list of fixtures (from Phaser.Physics.P2.Body#addPhaserPolygon)
    */
    Phaser.Physics.P2.FixtureList = function (list) {

        if (!Array.isArray(list))
        {
            list = [list];
        }

        this.rawList = list;
        this.init();
        this.parse(this.rawList);

    };

    Phaser.Physics.P2.FixtureList.prototype = {

        /**
        * @method Phaser.Physics.P2.FixtureList#init
        */
        init: function () {

            /**
            * @property {object} namedFixtures - Collect all fixtures with a key
            * @private
            */
            this.namedFixtures = {};

            /**
            * @property {Array} groupedFixtures - Collect all given fixtures per group index. Notice: Every fixture with a key also belongs to a group
            * @private
            */
            this.groupedFixtures = [];

            /**
            * @property {Array} allFixtures - This is a list of everything in this collection
            * @private
            */
            this.allFixtures = [];

        },

        /**
        * @method Phaser.Physics.P2.FixtureList#setCategory
        * @param {number} bit - The bit to set as the collision group.
        * @param {string} fixtureKey - Only apply to the fixture with the given key.
        */
        setCategory: function (bit, fixtureKey) {

            var setter = function(fixture) {
                fixture.collisionGroup = bit;
            };

            this.getFixtures(fixtureKey).forEach(setter);

        },

        /**
        * @method Phaser.Physics.P2.FixtureList#setMask
        * @param {number} bit - The bit to set as the collision mask
        * @param {string} fixtureKey - Only apply to the fixture with the given key
        */
        setMask: function (bit, fixtureKey) {

            var setter = function(fixture) {
                fixture.collisionMask = bit;
            };

            this.getFixtures(fixtureKey).forEach(setter);

        },

        /**
        * @method Phaser.Physics.P2.FixtureList#setSensor
        * @param {boolean} value - sensor true or false
        * @param {string} fixtureKey - Only apply to the fixture with the given key
        */
        setSensor: function (value, fixtureKey) {

            var setter = function(fixture) {
                fixture.sensor = value;
            };

            this.getFixtures(fixtureKey).forEach(setter);

        },

        /**
        * @method Phaser.Physics.P2.FixtureList#setMaterial
        * @param {Object} material - The contact material for a fixture
        * @param {string} fixtureKey - Only apply to the fixture with the given key
        */
        setMaterial: function (material, fixtureKey) {

            var setter = function(fixture) {
                fixture.material = material;
            };

            this.getFixtures(fixtureKey).forEach(setter);

        },

        /**
        * Accessor to get either a list of specified fixtures by key or the whole fixture list
        *
        * @method Phaser.Physics.P2.FixtureList#getFixtures
        * @param {array} keys - A list of fixture keys
        */
        getFixtures: function (keys) {

            var fixtures = [];

            if (keys)
            {
                if (!(keys instanceof Array))
                {
                    keys = [keys];
                }

                var self = this;
                keys.forEach(function(key) {
                    if (self.namedFixtures[key])
                    {
                        fixtures.push(self.namedFixtures[key]);
                    }
                });

                return this.flatten(fixtures);

            }
            else
            {
                return this.allFixtures;
            }

        },

        /**
        * Accessor to get either a single fixture by its key.
        *
        * @method Phaser.Physics.P2.FixtureList#getFixtureByKey
        * @param {string} key - The key of the fixture.
        */
        getFixtureByKey: function (key) {

            return this.namedFixtures[key];

        },

        /**
        * Accessor to get a group of fixtures by its group index.
        *
        * @method Phaser.Physics.P2.FixtureList#getGroup
        * @param {number} groupID - The group index.
        */
        getGroup: function (groupID) {

            return this.groupedFixtures[groupID];

        },

        /**
        * Parser for the output of Phaser.Physics.P2.Body#addPhaserPolygon
        *
        * @method Phaser.Physics.P2.FixtureList#parse
        */
        parse: function () {

            var key, value, _ref, _results;
            _ref = this.rawList;
            _results = [];

            for (key in _ref)
            {
                value = _ref[key];

                if (!isNaN(key - 0))
                {
                    this.groupedFixtures[key] = this.groupedFixtures[key] || [];
                    this.groupedFixtures[key] = this.groupedFixtures[key].concat(value);
                }
                else
                {
                    this.namedFixtures[key] = this.flatten(value);
                }

                _results.push(this.allFixtures = this.flatten(this.groupedFixtures));
            }

        },

        /**
        * A helper to flatten arrays. This is very useful as the fixtures are nested from time to time due to the way P2 creates and splits polygons.
        *
        * @method Phaser.Physics.P2.FixtureList#flatten
        * @param {array} array - The array to flatten. Notice: This will happen recursive not shallow.
        */
        flatten: function (array) {

            var result, self;
            result = [];
            self = arguments.callee;

            array.forEach(function(item) {
                return Array.prototype.push.apply(result, (Array.isArray(item) ? self(item) : [item]));
            });

            return result;

        }

    };