odin/src/odin/core/input/touches.js

Node.js Canvas/WebGL Javascript Game Framework

if (typeof(define) !== "function") {
    var define = require("amdefine")(module);
}
define([
        "odin/base/object_pool",
        "odin/core/input/touch"
    ],
    function(ObjectPool, Touch) {
        "use strict";


        var TOUCH_POOL = new ObjectPool(Touch),
            OBJECT_POOL = new ObjectPool(Object);


        function Touches() {

            Array.call(this);
            this._SYNC = {};
        }

        Touches.prototype = Object.create(Array.prototype);
        Touches.prototype.constructor = Touches;
        Touches.TOUCH_POOL = TOUCH_POOL;

        Touches.prototype.start = function(index, targetTouch) {
            var touch = TOUCH_POOL.create();

            touch.clear();
            touch.id = targetTouch.identifier;
            touch.fromEvent(targetTouch);

            this.push(touch);

            return touch;
        };


        Touches.prototype.end = function(index, targetTouch) {
            var touch = this[index];

            TOUCH_POOL.removeObject(touch);
            this.splice(index, 1);

            return touch;
        };


        Touches.prototype.cancel = function() {

            TOUCH_POOL.clear();
            this.length = 0;

            return this;
        };


        Touches.prototype.move = function(index, targetTouch) {
            var touch = this[index];

            touch.fromEvent(targetTouch);

            return touch;
        };


        Touches.prototype.toSYNC = function(json) {
            json || (json = this._SYNC);
            var jsonTouches = json.touches || (json.touches = []),
                i = this.length;

            jsonTouches.length = 0;
            OBJECT_POOL.clear();

            while (i--) jsonTouches[i] = this[i].toSYNC(OBJECT_POOL.create());

            return json;
        };


        Touches.prototype.fromSYNC = function(json) {
            var jsonTouches = json.touches,
                i = jsonTouches.length;

            this.length = 0;
            TOUCH_POOL.clear();

            while (i--) this[i] = TOUCH_POOL.create().fromSYNC(jsonTouches[i]);

            return this;
        };


        Touches.prototype.toJSON = function(json) {
            json || (json = {});
            var jsonTouches = json.touches || (json.touches = []),
                i;

            for (i = this.length; i--;) jsonTouches[i] = this[i].toJSON(jsonTouches[i]);
            return json;
        };


        Touches.prototype.fromJSON = function(json) {
            var jsonTouches = json.touches,
                touch, i, j, tl;

            for (i = jsonTouches.length, tl = this.length, j = tl; i--;) {
                if (i < tl) {
                    this.splice(j--, 1);
                    TOUCH_POOL.removeObject(this[j]);
                }

                if ((touch = this[i])) {
                    touch.fromJSON(jsonTouches[i]);
                } else {
                    this[i] = TOUCH_POOL.create().fromJSON(jsonTouches[i]);
                }
            }

            return this;
        };


        return Touches;
    }
);