Utilities.js

K2.loadImageArray = function (args) {

    this.onCompletion = function() {

        // Call the callback if there's one.
        if (typeof (this.onComplete) === 'function') {
            var final_status = this.pollStatus();
            var retvalue = {
                imagesArray: this.imagesArray,
                status: final_status
            };
            this.onComplete(retvalue);
        }

        return;
    };

    this.onLoad = function(that) {
        return function() {
            that.objectsLoaded += 1;
            that.check(that.onSingle, this);
        };
    };

    this.onError = function(that) {
        return function() {
            that.objectsError += 1;
            that.check(that.onErr, this);
        };
    };

    this.check = function(callback, imageObj) {

        if (typeof(callback) === 'function') {
                var temp_status = this.pollStatus();
                callback({
                    obj: imageObj,
                    status: temp_status
                });
        }
            if (this.objectsLoaded + this.objectsError === this.objectsTotal) {
                this.onCompletion();
            }
    };

    this.pollStatus = function() {
        return {
                id: this.ID,
                loaded: this.objectsLoaded,
                error: this.objectsError,
                total: this.objectsTotal
                };
    };

    // The user will recognize this particular instance by ID
    this.ID = args.ID;

    // Optional callbacks
    this.onComplete = args.onComplete;
    this.onSingle = args.onSingle;
    this.onErr = args.onError;

    // Statistics
    this.objectsLoaded = 0;
    this.objectsError = 0;
    this.objectsTotal = args.imageNames.length;
    this.imagesArray = [];

    // Load images from names
    for (var i = 0; i < this.objectsTotal; i += 1) {
        this.imagesArray[i] = new Image();
        this.imagesArray[i].onload = this.onLoad(this);
        this.imagesArray[i].onerror = this.onError(this);
        this.imagesArray[i].src = args.imageNames[i];
    }
};

K2.loadMultipleImages = function(args) {

    this.loadingManager = function() {
        // Storage the closurage.
        var that = this;
        return function(loaderStatus) {
            var ls = loaderStatus;
                    // console.log (ls.status.id, " called back to say everything is loaded.");

                    // Update the element status
                    if (that.loaders[ls.status.id] !== undefined) {
                        that.loaders[ls.status.id].done = true;
                        that.loaders[ls.status.id].images = that.loaders[ls.status.id].imageArray.imagesArray;
                        // Call the singleArray callback
                        if (typeof (that.onSingleArray) === 'function') {
                            that.onSingleArray(loaderStatus);
                        }
                    }
                    else {
                        throw new Error('in loaders, ' + ls.status.id + ' is undefined');
                    }

                    // Check if every registered element is complete.
                    for (var element in that.loaders) {
                        if (that.loaders.hasOwnProperty(element)) {
                            if (that.loaders[element].done !== true) {
                                // console.log ("status of element ", element, " is not true: ", that.loaders[element].done);
                                // Return, we're not done yet.
                                return;
                            }
                        }
                    }

                    that.onComplete(that.loaders);
            };
        };

     this.errorManager = function() {
         // Storage the closurage.
        var that = this;
        return function(errorStatus) {
            if (typeof (that.onError) === 'function') {
                that.onError(errorStatus);
            }
        };
    };

     this.singleManager = function() {
         // Storage the closurage.
        var that = this;
        return function(singleStatus) {
            if (typeof (that.onSingle) === 'function') {
                that.onSingle(singleStatus);
            }
        };
    };


    this.multipleImages = args.multipleImages;
    this.onComplete = args.onComplete;
    this.onError = args.onError;
    this.onSingle = args.onSingle;
    this.onSingleArray = args.onSingleArray;
    this.loaders = {};

    // init as many loadImageArray as needed, by the mighty powers of object
    // composition.
    for (var i = 0; i < this.multipleImages.length; i += 1) {

        var loader = {};
        loader.imageArray = new loadImageArray({ID: this.multipleImages[i].ID,
                                                 imageNames: this.multipleImages[i].imageNames,
                                                 onComplete: this.loadingManager(),
                                                 onError: this.errorManager(),
                                                 onSingle: this.singleManager()
                                                });
        loader.done = false;
        this.loaders[this.multipleImages[i].ID] = loader;
    }

};

function memoize(func, max) {
    max = max || 5000;
    return (function() {
        var cache = {};
        var remaining = max;
        function fn(n) {
            return (cache[n] || (remaining-- > 0 ? (cache[n] = func(n)) : func(n)));
        }
        return fn;
    }());
}

K2.GenericUtils = {};

K2.GenericUtils.clone = function(obj) {
    var copy;
    
    // Handle the 3 simple types, and null or undefined
    if (null === obj || "object" !== typeof obj) return obj;

    // Handle Date
    if (obj instanceof Date) {
        copy = new Date();
        copy.setTime(obj.getTime());
        return copy;
    }

    // Handle Array
    if (obj instanceof Array) {
        copy = [];
        for (var i = 0, len = obj.length; i < len; ++i) {
            copy[i] = K2.GenericUtils.clone(obj[i]);
        }
        return copy;
    }

    // Handle Object
    if (obj instanceof Object) {
        copy = {};
        for (var attr in obj) {
            if (obj.hasOwnProperty(attr)) copy[attr] = K2.GenericUtils.clone(obj[attr]);
        }
        return copy;
    }

    throw new Error("Unable to copy obj! Its type isn't supported.");
};

K2.MathUtils = {};

K2.MathUtils.linearRange = function (a, b, y, z, c) {
    // Input:   value c between a and b
    // Output:  value x between y and z
    var x = (c - a) * (z - y) / (b - a) + y;
    return x;
};

K2.MathUtils.distance = function (x1, y1, x2, y2) {
    return Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(y1 - y2, 2));
};

K2.MathUtils.fact_table = [1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800, 39916800, 479001600, 6227020800, 87178291200, 1307674368000, 20922789888000, 355687428096000, 6402373705728000, 121645100408832000, 2432902008176640000, 51090942171709440000, 1124000727777607680000, 25852016738884976640000, 620448401733239439360000, 15511210043330985984000000, 403291461126605635584000000, 10888869450418352160768000000, 304888344611713860501504000000, 8841761993739701954543616000000, 265252859812191058636308480000000, 8222838654177922817725562880000000, 263130836933693530167218012160000000, 8683317618811886495518194401280000000, 295232799039604140847618609643520000000, 10333147966386144929666651337523200000000, 371993326789901217467999448150835200000000, 13763753091226345046315979581580902400000000, 523022617466601111760007224100074291200000000, 20397882081197443358640281739902897356800000000, 815915283247897734345611269596115894272000000000, 33452526613163807108170062053440751665152000000000, 1405006117752879898543142606244511569936384000000000, 60415263063373835637355132068513997507264512000000000, 2658271574788448768043625811014615890319638528000000000, 119622220865480194561963161495657715064383733760000000000, 5502622159812088949850305428800254892961651752960000000000, 258623241511168180642964355153611979969197632389120000000000, 12413915592536072670862289047373375038521486354677760000000000, 608281864034267560872252163321295376887552831379210240000000000, 30414093201713378043612608166064768844377641568960512000000000000, 1551118753287382280224243016469303211063259720016986112000000000000, 80658175170943878571660636856403766975289505440883277824000000000000, 4274883284060025564298013753389399649690343788366813724672000000000000, 230843697339241380472092742683027581083278564571807941132288000000000000, 12696403353658275925965100847566516959580321051449436762275840000000000000, 710998587804863451854045647463724949736497978881168458687447040000000000000, 40526919504877216755680601905432322134980384796226602145184481280000000000000, 2350561331282878571829474910515074683828862318181142924420699914240000000000000, 138683118545689835737939019720389406345902876772687432540821294940160000000000000, 8320987112741390144276341183223364380754172606361245952449277696409600000000000000, 507580213877224798800856812176625227226004528988036003099405939480985600000000000000, 31469973260387937525653122354950764088012280797258232192163168247821107200000000000000, 1982608315404440064116146708361898137544773690227268628106279599612729753600000000000000, 126886932185884164103433389335161480802865516174545192198801894375214704230400000000000000, 8247650592082470666723170306785496252186258551345437492922123134388955774976000000000000000, 544344939077443064003729240247842752644293064388798874532860126869671081148416000000000000000, 36471110918188685288249859096605464427167635314049524593701628500267962436943872000000000000000, 2480035542436830599600990418569171581047399201355367672371710738018221445712183296000000000000000, 171122452428141311372468338881272839092270544893520369393648040923257279754140647424000000000000000, 11978571669969891796072783721689098736458938142546425857555362864628009582789845319680000000000000000, 850478588567862317521167644239926010288584608120796235886430763388588680378079017697280000000000000000, 61234458376886086861524070385274672740778091784697328983823014963978384987221689274204160000000000000000, 4470115461512684340891257138125051110076800700282905015819080092370422104067183317016903680000000000000000, 330788544151938641225953028221253782145683251820934971170611926835411235700971565459250872320000000000000000, 24809140811395398091946477116594033660926243886570122837795894512655842677572867409443815424000000000000000000, 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3314240134565353266999387579130131288000666286242049487118846032383059131291716864129885722968716753156177920000000000000000000, 281710411438055027694947944226061159480056634330574206405101912752560026159795933451040286452340924018275123200000000000000000000, 24227095383672732381765523203441259715284870552429381750838764496720162249742450276789464634901319465571660595200000000000000000000, 2107757298379527717213600518699389595229783738061356212322972511214654115727593174080683423236414793504734471782400000000000000000000, 185482642257398439114796845645546284380220968949399346684421580986889562184028199319100141244804501828416633516851200000000000000000000, 16507955160908461081216919262453619309839666236496541854913520707833171034378509739399912570787600662729080382999756800000000000000000000, 1485715964481761497309522733620825737885569961284688766942216863704985393094065876545992131370884059645617234469978112000000000000000000000, 135200152767840296255166568759495142147586866476906677791741734597153670771559994765685283954750449427751168336768008192000000000000000000000, 12438414054641307255475324325873553077577991715875414356840239582938137710983519518443046123837041347353107486982656753664000000000000000000000, 1156772507081641574759205162306240436214753229576413535186142281213246807121467315215203289516844845303838996289387078090752000000000000000000000, 108736615665674308027365285256786601004186803580182872307497374434045199869417927630229109214583415458560865651202385340530688000000000000000000000, 10329978488239059262599702099394727095397746340117372869212250571234293987594703124871765375385424468563282236864226607350415360000000000000000000000, 991677934870949689209571401541893801158183648651267795444376054838492222809091499987689476037000748982075094738965754305639874560000000000000000000000, 96192759682482119853328425949563698712343813919172976158104477319333745612481875498805879175589072651261284189679678167647067832320000000000000000000000, 9426890448883247745626185743057242473809693764078951663494238777294707070023223798882976159207729119823605850588608460429412647567360000000000000000000000, 933262154439441526816992388562667004907159682643816214685929638952175999932299156089414639761565182862536979208272237582511852109168640000000000000000000000, 93326215443944152681699238856266700490715968264381621468592963895217599993229915608941463976156518286253697920827223758251185210916864000000000000000000000000];
K2.MathUtils.fact_lookup = function (n) {
    if (0 < n <= 100) {
        return K2.MathUtils.fact_table[n];
    }
    else {
        var rval = 1;
        for (var i = 2; i <= n; i++)
            rval = rval * i;
        return rval;
    }
};

K2.CanvasUtils = {};

K2.CanvasUtils.drawRotate = function (ctx, args /*{image, x, y, rot}*/) {
    ctx.save();
    ctx.translate(args.x + (args.image.width / 2), args.y + (args.image.height / 2));
    ctx.rotate(args.rot);
    ctx.translate(-(args.image.width / 2) - args.x, -(args.image.height / 2) - args.y);
    ctx.drawImage(args.image, args.x, args.y);
    ctx.restore();
};