three.js/examples/jsm/libs/tween.module.js

/**
 * The Ease class provides a collection of easing functions for use with tween.js.
 */
var Easing = Object.freeze({
    Linear: Object.freeze({
        None: function (amount) {
            return amount;
        },
        In: function (amount) {
            return this.None(amount);
        },
        Out: function (amount) {
            return this.None(amount);
        },
        InOut: function (amount) {
            return this.None(amount);
        },
    }),
    Quadratic: Object.freeze({
        In: function (amount) {
            return amount * amount;
        },
        Out: function (amount) {
            return amount * (2 - amount);
        },
        InOut: function (amount) {
            if ((amount *= 2) < 1) {
                return 0.5 * amount * amount;
            }
            return -0.5 * (--amount * (amount - 2) - 1);
        },
    }),
    Cubic: Object.freeze({
        In: function (amount) {
            return amount * amount * amount;
        },
        Out: function (amount) {
            return --amount * amount * amount + 1;
        },
        InOut: function (amount) {
            if ((amount *= 2) < 1) {
                return 0.5 * amount * amount * amount;
            }
            return 0.5 * ((amount -= 2) * amount * amount + 2);
        },
    }),
    Quartic: Object.freeze({
        In: function (amount) {
            return amount * amount * amount * amount;
        },
        Out: function (amount) {
            return 1 - --amount * amount * amount * amount;
        },
        InOut: function (amount) {
            if ((amount *= 2) < 1) {
                return 0.5 * amount * amount * amount * amount;
            }
            return -0.5 * ((amount -= 2) * amount * amount * amount - 2);
        },
    }),
    Quintic: Object.freeze({
        In: function (amount) {
            return amount * amount * amount * amount * amount;
        },
        Out: function (amount) {
            return --amount * amount * amount * amount * amount + 1;
        },
        InOut: function (amount) {
            if ((amount *= 2) < 1) {
                return 0.5 * amount * amount * amount * amount * amount;
            }
            return 0.5 * ((amount -= 2) * amount * amount * amount * amount + 2);
        },
    }),
    Sinusoidal: Object.freeze({
        In: function (amount) {
            return 1 - Math.sin(((1.0 - amount) * Math.PI) / 2);
        },
        Out: function (amount) {
            return Math.sin((amount * Math.PI) / 2);
        },
        InOut: function (amount) {
            return 0.5 * (1 - Math.sin(Math.PI * (0.5 - amount)));
        },
    }),
    Exponential: Object.freeze({
        In: function (amount) {
            return amount === 0 ? 0 : Math.pow(1024, amount - 1);
        },
        Out: function (amount) {
            return amount === 1 ? 1 : 1 - Math.pow(2, -10 * amount);
        },
        InOut: function (amount) {
            if (amount === 0) {
                return 0;
            }
            if (amount === 1) {
                return 1;
            }
            if ((amount *= 2) < 1) {
                return 0.5 * Math.pow(1024, amount - 1);
            }
            return 0.5 * (-Math.pow(2, -10 * (amount - 1)) + 2);
        },
    }),
    Circular: Object.freeze({
        In: function (amount) {
            return 1 - Math.sqrt(1 - amount * amount);
        },
        Out: function (amount) {
            return Math.sqrt(1 - --amount * amount);
        },
        InOut: function (amount) {
            if ((amount *= 2) < 1) {
                return -0.5 * (Math.sqrt(1 - amount * amount) - 1);
            }
            return 0.5 * (Math.sqrt(1 - (amount -= 2) * amount) + 1);
        },
    }),
    Elastic: Object.freeze({
        In: function (amount) {
            if (amount === 0) {
                return 0;
            }
            if (amount === 1) {
                return 1;
            }
            return -Math.pow(2, 10 * (amount - 1)) * Math.sin((amount - 1.1) * 5 * Math.PI);
        },
        Out: function (amount) {
            if (amount === 0) {
                return 0;
            }
            if (amount === 1) {
                return 1;
            }
            return Math.pow(2, -10 * amount) * Math.sin((amount - 0.1) * 5 * Math.PI) + 1;
        },
        InOut: function (amount) {
            if (amount === 0) {
                return 0;
            }
            if (amount === 1) {
                return 1;
            }
            amount *= 2;
            if (amount < 1) {
                return -0.5 * Math.pow(2, 10 * (amount - 1)) * Math.sin((amount - 1.1) * 5 * Math.PI);
            }
            return 0.5 * Math.pow(2, -10 * (amount - 1)) * Math.sin((amount - 1.1) * 5 * Math.PI) + 1;
        },
    }),
    Back: Object.freeze({
        In: function (amount) {
            var s = 1.70158;
            return amount === 1 ? 1 : amount * amount * ((s + 1) * amount - s);
        },
        Out: function (amount) {
            var s = 1.70158;
            return amount === 0 ? 0 : --amount * amount * ((s + 1) * amount + s) + 1;
        },
        InOut: function (amount) {
            var s = 1.70158 * 1.525;
            if ((amount *= 2) < 1) {
                return 0.5 * (amount * amount * ((s + 1) * amount - s));
            }
            return 0.5 * ((amount -= 2) * amount * ((s + 1) * amount + s) + 2);
        },
    }),
    Bounce: Object.freeze({
        In: function (amount) {
            return 1 - Easing.Bounce.Out(1 - amount);
        },
        Out: function (amount) {
            if (amount < 1 / 2.75) {
                return 7.5625 * amount * amount;
            }
            else if (amount < 2 / 2.75) {
                return 7.5625 * (amount -= 1.5 / 2.75) * amount + 0.75;
            }
            else if (amount < 2.5 / 2.75) {
                return 7.5625 * (amount -= 2.25 / 2.75) * amount + 0.9375;
            }
            else {
                return 7.5625 * (amount -= 2.625 / 2.75) * amount + 0.984375;
            }
        },
        InOut: function (amount) {
            if (amount < 0.5) {
                return Easing.Bounce.In(amount * 2) * 0.5;
            }
            return Easing.Bounce.Out(amount * 2 - 1) * 0.5 + 0.5;
        },
    }),
    generatePow: function (power) {
        if (power === void 0) { power = 4; }
        power = power < Number.EPSILON ? Number.EPSILON : power;
        power = power > 10000 ? 10000 : power;
        return {
            In: function (amount) {
                return Math.pow(amount, power);
            },
            Out: function (amount) {
                return 1 - Math.pow((1 - amount), power);
            },
            InOut: function (amount) {
                if (amount < 0.5) {
                    return Math.pow((amount * 2), power) / 2;
                }
                return (1 - Math.pow((2 - amount * 2), power)) / 2 + 0.5;
            },
        };
    },
});

var now = function () { return performance.now(); };

/**
 * Controlling groups of tweens
 *
 * Using the TWEEN singleton to manage your tweens can cause issues in large apps with many components.
 * In these cases, you may want to create your own smaller groups of tween
 */
var Group = /** @class */ (function () {
    function Group() {
        this._tweens = {};
        this._tweensAddedDuringUpdate = {};
    }
    Group.prototype.getAll = function () {
        var _this = this;
        return Object.keys(this._tweens).map(function (tweenId) {
            return _this._tweens[tweenId];
        });
    };
    Group.prototype.removeAll = function () {
        this._tweens = {};
    };
    Group.prototype.add = function (tween) {
        this._tweens[tween.getId()] = tween;
        this._tweensAddedDuringUpdate[tween.getId()] = tween;
    };
    Group.prototype.remove = function (tween) {
        delete this._tweens[tween.getId()];
        delete this._tweensAddedDuringUpdate[tween.getId()];
    };
    Group.prototype.update = function (time, preserve) {
        if (time === void 0) { time = now(); }
        if (preserve === void 0) { preserve = false; }
        var tweenIds = Object.keys(this._tweens);
        if (tweenIds.length === 0) {
            return false;
        }
        // Tweens are updated in "batches". If you add a new tween during an
        // update, then the new tween will be updated in the next batch.
        // If you remove a tween during an update, it may or may not be updated.
        // However, if the removed tween was added during the current batch,
        // then it will not be updated.
        while (tweenIds.length > 0) {
            this._tweensAddedDuringUpdate = {};
            for (var i = 0; i < tweenIds.length; i++) {
                var tween = this._tweens[tweenIds[i]];
                var autoStart = !preserve;
                if (tween && tween.update(time, autoStart) === false && !preserve) {
                    delete this._tweens[tweenIds[i]];
                }
            }
            tweenIds = Object.keys(this._tweensAddedDuringUpdate);
        }
        return true;
    };
    return Group;
}());

/**
 *
 */
var Interpolation = {
    Linear: function (v, k) {
        var m = v.length - 1;
        var f = m * k;
        var i = Math.floor(f);
        var fn = Interpolation.Utils.Linear;
        if (k < 0) {
            return fn(v[0], v[1], f);
        }
        if (k > 1) {
            return fn(v[m], v[m - 1], m - f);
        }
        return fn(v[i], v[i + 1 > m ? m : i + 1], f - i);
    },
    Bezier: function (v, k) {
        var b = 0;
        var n = v.length - 1;
        var pw = Math.pow;
        var bn = Interpolation.Utils.Bernstein;
        for (var i = 0; i <= n; i++) {
            b += pw(1 - k, n - i) * pw(k, i) * v[i] * bn(n, i);
        }
        return b;
    },
    CatmullRom: function (v, k) {
        var m = v.length - 1;
        var f = m * k;
        var i = Math.floor(f);
        var fn = Interpolation.Utils.CatmullRom;
        if (v[0] === v[m]) {
            if (k < 0) {
                i = Math.floor((f = m * (1 + k)));
            }
            return fn(v[(i - 1 + m) % m], v[i], v[(i + 1) % m], v[(i + 2) % m], f - i);
        }
        else {
            if (k < 0) {
                return v[0] - (fn(v[0], v[0], v[1], v[1], -f) - v[0]);
            }
            if (k > 1) {
                return v[m] - (fn(v[m], v[m], v[m - 1], v[m - 1], f - m) - v[m]);
            }
            return fn(v[i ? i - 1 : 0], v[i], v[m < i + 1 ? m : i + 1], v[m < i + 2 ? m : i + 2], f - i);
        }
    },
    Utils: {
        Linear: function (p0, p1, t) {
            return (p1 - p0) * t + p0;
        },
        Bernstein: function (n, i) {
            var fc = Interpolation.Utils.Factorial;
            return fc(n) / fc(i) / fc(n - i);
        },
        Factorial: (function () {
            var a = [1];
            return function (n) {
                var s = 1;
                if (a[n]) {
                    return a[n];
                }
                for (var i = n; i > 1; i--) {
                    s *= i;
                }
                a[n] = s;
                return s;
            };
        })(),
        CatmullRom: function (p0, p1, p2, p3, t) {
            var v0 = (p2 - p0) * 0.5;
            var v1 = (p3 - p1) * 0.5;
            var t2 = t * t;
            var t3 = t * t2;
            return (2 * p1 - 2 * p2 + v0 + v1) * t3 + (-3 * p1 + 3 * p2 - 2 * v0 - v1) * t2 + v0 * t + p1;
        },
    },
};

/**
 * Utils
 */
var Sequence = /** @class */ (function () {
    function Sequence() {
    }
    Sequence.nextId = function () {
        return Sequence._nextId++;
    };
    Sequence._nextId = 0;
    return Sequence;
}());

var mainGroup = new Group();

/**
 * Tween.js - Licensed under the MIT license
 * https://github.com/tweenjs/tween.js
 * ----------------------------------------------
 *
 * See https://github.com/tweenjs/tween.js/graphs/contributors for the full list of contributors.
 * Thank you all, you're awesome!
 */
var Tween = /** @class */ (function () {
    function Tween(_object, _group) {
        if (_group === void 0) { _group = mainGroup; }
        this._object = _object;
        this._group = _group;
        this._isPaused = false;
        this._pauseStart = 0;
        this._valuesStart = {};
        this._valuesEnd = {};
        this._valuesStartRepeat = {};
        this._duration = 1000;
        this._isDynamic = false;
        this._initialRepeat = 0;
        this._repeat = 0;
        this._yoyo = false;
        this._isPlaying = false;
        this._reversed = false;
        this._delayTime = 0;
        this._startTime = 0;
        this._easingFunction = Easing.Linear.None;
        this._interpolationFunction = Interpolation.Linear;
        // eslint-disable-next-line
        this._chainedTweens = [];
        this._onStartCallbackFired = false;
        this._onEveryStartCallbackFired = false;
        this._id = Sequence.nextId();
        this._isChainStopped = false;
        this._propertiesAreSetUp = false;
        this._goToEnd = false;
    }
    Tween.prototype.getId = function () {
        return this._id;
    };
    Tween.prototype.isPlaying = function () {
        return this._isPlaying;
    };
    Tween.prototype.isPaused = function () {
        return this._isPaused;
    };
    Tween.prototype.to = function (target, duration) {
        if (duration === void 0) { duration = 1000; }
        if (this._isPlaying)
            throw new Error('Can not call Tween.to() while Tween is already started or paused. Stop the Tween first.');
        this._valuesEnd = target;
        this._propertiesAreSetUp = false;
        this._duration = duration;
        return this;
    };
    Tween.prototype.duration = function (duration) {
        if (duration === void 0) { duration = 1000; }
        this._duration = duration;
        return this;
    };
    Tween.prototype.dynamic = function (dynamic) {
        if (dynamic === void 0) { dynamic = false; }
        this._isDynamic = dynamic;
        return this;
    };
    Tween.prototype.start = function (time, overrideStartingValues) {
        if (time === void 0) { time = now(); }
        if (overrideStartingValues === void 0) { overrideStartingValues = false; }
        if (this._isPlaying) {
            return this;
        }
        // eslint-disable-next-line
        this._group && this._group.add(this);
        this._repeat = this._initialRepeat;
        if (this._reversed) {
            // If we were reversed (f.e. using the yoyo feature) then we need to
            // flip the tween direction back to forward.
            this._reversed = false;
            for (var property in this._valuesStartRepeat) {
                this._swapEndStartRepeatValues(property);
                this._valuesStart[property] = this._valuesStartRepeat[property];
            }
        }
        this._isPlaying = true;
        this._isPaused = false;
        this._onStartCallbackFired = false;
        this._onEveryStartCallbackFired = false;
        this._isChainStopped = false;
        this._startTime = time;
        this._startTime += this._delayTime;
        if (!this._propertiesAreSetUp || overrideStartingValues) {
            this._propertiesAreSetUp = true;
            // If dynamic is not enabled, clone the end values instead of using the passed-in end values.
            if (!this._isDynamic) {
                var tmp = {};
                for (var prop in this._valuesEnd)
                    tmp[prop] = this._valuesEnd[prop];
                this._valuesEnd = tmp;
            }
            this._setupProperties(this._object, this._valuesStart, this._valuesEnd, this._valuesStartRepeat, overrideStartingValues);
        }
        return this;
    };
    Tween.prototype.startFromCurrentValues = function (time) {
        return this.start(time, true);
    };
    Tween.prototype._setupProperties = function (_object, _valuesStart, _valuesEnd, _valuesStartRepeat, overrideStartingValues) {
        for (var property in _valuesEnd) {
            var startValue = _object[property];
            var startValueIsArray = Array.isArray(startValue);
            var propType = startValueIsArray ? 'array' : typeof startValue;
            var isInterpolationList = !startValueIsArray && Array.isArray(_valuesEnd[property]);
            // If `to()` specifies a property that doesn't exist in the source object,
            // we should not set that property in the object
            if (propType === 'undefined' || propType === 'function') {
                continue;
            }
            // Check if an Array was provided as property value
            if (isInterpolationList) {
                var endValues = _valuesEnd[property];
                if (endValues.length === 0) {
                    continue;
                }
                // Handle an array of relative values.
                // Creates a local copy of the Array with the start value at the front
                var temp = [startValue];
                for (var i = 0, l = endValues.length; i < l; i += 1) {
                    var value = this._handleRelativeValue(startValue, endValues[i]);
                    if (isNaN(value)) {
                        isInterpolationList = false;
                        console.warn('Found invalid interpolation list. Skipping.');
                        break;
                    }
                    temp.push(value);
                }
                if (isInterpolationList) {
                    // if (_valuesStart[property] === undefined) { // handle end values only the first time. NOT NEEDED? setupProperties is now guarded by _propertiesAreSetUp.
                    _valuesEnd[property] = temp;
                    // }
                }
            }
            // handle the deepness of the values
            if ((propType === 'object' || startValueIsArray) && startValue && !isInterpolationList) {
                _valuesStart[property] = startValueIsArray ? [] : {};
                var nestedObject = startValue;
                for (var prop in nestedObject) {
                    _valuesStart[property][prop] = nestedObject[prop];
                }
                // TODO? repeat nested values? And yoyo? And array values?
                _valuesStartRepeat[property] = startValueIsArray ? [] : {};
                var endValues = _valuesEnd[property];
                // If dynamic is not enabled, clone the end values instead of using the passed-in end values.
                if (!this._isDynamic) {
                    var tmp = {};
                    for (var prop in endValues)
                        tmp[prop] = endValues[prop];
                    _valuesEnd[property] = endValues = tmp;
                }
                this._setupProperties(nestedObject, _valuesStart[property], endValues, _valuesStartRepeat[property], overrideStartingValues);
            }
            else {
                // Save the starting value, but only once unless override is requested.
                if (typeof _valuesStart[property] === 'undefined' || overrideStartingValues) {
                    _valuesStart[property] = startValue;
                }
                if (!startValueIsArray) {
                    // eslint-disable-next-line
                    // @ts-ignore FIXME?
                    _valuesStart[property] *= 1.0; // Ensures we're using numbers, not strings
                }
                if (isInterpolationList) {
                    // eslint-disable-next-line
                    // @ts-ignore FIXME?
                    _valuesStartRepeat[property] = _valuesEnd[property].slice().reverse();
                }
                else {
                    _valuesStartRepeat[property] = _valuesStart[property] || 0;
                }
            }
        }
    };
    Tween.prototype.stop = function () {
        if (!this._isChainStopped) {
            this._isChainStopped = true;
            this.stopChainedTweens();
        }
        if (!this._isPlaying) {
            return this;
        }
        // eslint-disable-next-line
        this._group && this._group.remove(this);
        this._isPlaying = false;
        this._isPaused = false;
        if (this._onStopCallback) {
            this._onStopCallback(this._object);
        }
        return this;
    };
    Tween.prototype.end = function () {
        this._goToEnd = true;
        this.update(Infinity);
        return this;
    };
    Tween.prototype.pause = function (time) {
        if (time === void 0) { time = now(); }
        if (this._isPaused || !this._isPlaying) {
            return this;
        }
        this._isPaused = true;
        this._pauseStart = time;
        // eslint-disable-next-line
        this._group && this._group.remove(this);
        return this;
    };
    Tween.prototype.resume = function (time) {
        if (time === void 0) { time = now(); }
        if (!this._isPaused || !this._isPlaying) {
            return this;
        }
        this._isPaused = false;
        this._startTime += time - this._pauseStart;
        this._pauseStart = 0;
        // eslint-disable-next-line
        this._group && this._group.add(this);
        return this;
    };
    Tween.prototype.stopChainedTweens = function () {
        for (var i = 0, numChainedTweens = this._chainedTweens.length; i < numChainedTweens; i++) {
            this._chainedTweens[i].stop();
        }
        return this;
    };
    Tween.prototype.group = function (group) {
        if (group === void 0) { group = mainGroup; }
        this._group = group;
        return this;
    };
    Tween.prototype.delay = function (amount) {
        if (amount === void 0) { amount = 0; }
        this._delayTime = amount;
        return this;
    };
    Tween.prototype.repeat = function (times) {
        if (times === void 0) { times = 0; }
        this._initialRepeat = times;
        this._repeat = times;
        return this;
    };
    Tween.prototype.repeatDelay = function (amount) {
        this._repeatDelayTime = amount;
        return this;
    };
    Tween.prototype.yoyo = function (yoyo) {
        if (yoyo === void 0) { yoyo = false; }
        this._yoyo = yoyo;
        return this;
    };
    Tween.prototype.easing = function (easingFunction) {
        if (easingFunction === void 0) { easingFunction = Easing.Linear.None; }
        this._easingFunction = easingFunction;
        return this;
    };
    Tween.prototype.interpolation = function (interpolationFunction) {
        if (interpolationFunction === void 0) { interpolationFunction = Interpolation.Linear; }
        this._interpolationFunction = interpolationFunction;
        return this;
    };
    // eslint-disable-next-line
    Tween.prototype.chain = function () {
        var tweens = [];
        for (var _i = 0; _i < arguments.length; _i++) {
            tweens[_i] = arguments[_i];
        }
        this._chainedTweens = tweens;
        return this;
    };
    Tween.prototype.onStart = function (callback) {
        this._onStartCallback = callback;
        return this;
    };
    Tween.prototype.onEveryStart = function (callback) {
        this._onEveryStartCallback = callback;
        return this;
    };
    Tween.prototype.onUpdate = function (callback) {
        this._onUpdateCallback = callback;
        return this;
    };
    Tween.prototype.onRepeat = function (callback) {
        this._onRepeatCallback = callback;
        return this;
    };
    Tween.prototype.onComplete = function (callback) {
        this._onCompleteCallback = callback;
        return this;
    };
    Tween.prototype.onStop = function (callback) {
        this._onStopCallback = callback;
        return this;
    };
    /**
     * @returns true if the tween is still playing after the update, false
     * otherwise (calling update on a paused tween still returns true because
     * it is still playing, just paused).
     */
    Tween.prototype.update = function (time, autoStart) {
        if (time === void 0) { time = now(); }
        if (autoStart === void 0) { autoStart = true; }
        if (this._isPaused)
            return true;
        var property;
        var elapsed;
        var endTime = this._startTime + this._duration;
        if (!this._goToEnd && !this._isPlaying) {
            if (time > endTime)
                return false;
            if (autoStart)
                this.start(time, true);
        }
        this._goToEnd = false;
        if (time < this._startTime) {
            return true;
        }
        if (this._onStartCallbackFired === false) {
            if (this._onStartCallback) {
                this._onStartCallback(this._object);
            }
            this._onStartCallbackFired = true;
        }
        if (this._onEveryStartCallbackFired === false) {
            if (this._onEveryStartCallback) {
                this._onEveryStartCallback(this._object);
            }
            this._onEveryStartCallbackFired = true;
        }
        elapsed = (time - this._startTime) / this._duration;
        elapsed = this._duration === 0 || elapsed > 1 ? 1 : elapsed;
        var value = this._easingFunction(elapsed);
        // properties transformations
        this._updateProperties(this._object, this._valuesStart, this._valuesEnd, value);
        if (this._onUpdateCallback) {
            this._onUpdateCallback(this._object, elapsed);
        }
        if (elapsed === 1) {
            if (this._repeat > 0) {
                if (isFinite(this._repeat)) {
                    this._repeat--;
                }
                // Reassign starting values, restart by making startTime = now
                for (property in this._valuesStartRepeat) {
                    if (!this._yoyo && typeof this._valuesEnd[property] === 'string') {
                        this._valuesStartRepeat[property] =
                            // eslint-disable-next-line
                            // @ts-ignore FIXME?
                            this._valuesStartRepeat[property] + parseFloat(this._valuesEnd[property]);
                    }
                    if (this._yoyo) {
                        this._swapEndStartRepeatValues(property);
                    }
                    this._valuesStart[property] = this._valuesStartRepeat[property];
                }
                if (this._yoyo) {
                    this._reversed = !this._reversed;
                }
                if (this._repeatDelayTime !== undefined) {
                    this._startTime = time + this._repeatDelayTime;
                }
                else {
                    this._startTime = time + this._delayTime;
                }
                if (this._onRepeatCallback) {
                    this._onRepeatCallback(this._object);
                }
                this._onEveryStartCallbackFired = false;
                return true;
            }
            else {
                if (this._onCompleteCallback) {
                    this._onCompleteCallback(this._object);
                }
                for (var i = 0, numChainedTweens = this._chainedTweens.length; i < numChainedTweens; i++) {
                    // Make the chained tweens start exactly at the time they should,
                    // even if the `update()` method was called way past the duration of the tween
                    this._chainedTweens[i].start(this._startTime + this._duration, false);
                }
                this._isPlaying = false;
                return false;
            }
        }
        return true;
    };
    Tween.prototype._updateProperties = function (_object, _valuesStart, _valuesEnd, value) {
        for (var property in _valuesEnd) {
            // Don't update properties that do not exist in the source object
            if (_valuesStart[property] === undefined) {
                continue;
            }
            var start = _valuesStart[property] || 0;
            var end = _valuesEnd[property];
            var startIsArray = Array.isArray(_object[property]);
            var endIsArray = Array.isArray(end);
            var isInterpolationList = !startIsArray && endIsArray;
            if (isInterpolationList) {
                _object[property] = this._interpolationFunction(end, value);
            }
            else if (typeof end === 'object' && end) {
                // eslint-disable-next-line
                // @ts-ignore FIXME?
                this._updateProperties(_object[property], start, end, value);
            }
            else {
                // Parses relative end values with start as base (e.g.: +10, -3)
                end = this._handleRelativeValue(start, end);
                // Protect against non numeric properties.
                if (typeof end === 'number') {
                    // eslint-disable-next-line
                    // @ts-ignore FIXME?
                    _object[property] = start + (end - start) * value;
                }
            }
        }
    };
    Tween.prototype._handleRelativeValue = function (start, end) {
        if (typeof end !== 'string') {
            return end;
        }
        if (end.charAt(0) === '+' || end.charAt(0) === '-') {
            return start + parseFloat(end);
        }
        return parseFloat(end);
    };
    Tween.prototype._swapEndStartRepeatValues = function (property) {
        var tmp = this._valuesStartRepeat[property];
        var endValue = this._valuesEnd[property];
        if (typeof endValue === 'string') {
            this._valuesStartRepeat[property] = this._valuesStartRepeat[property] + parseFloat(endValue);
        }
        else {
            this._valuesStartRepeat[property] = this._valuesEnd[property];
        }
        this._valuesEnd[property] = tmp;
    };
    return Tween;
}());

var VERSION = '21.0.0';

/**
 * Tween.js - Licensed under the MIT license
 * https://github.com/tweenjs/tween.js
 * ----------------------------------------------
 *
 * See https://github.com/tweenjs/tween.js/graphs/contributors for the full list of contributors.
 * Thank you all, you're awesome!
 */
var nextId = Sequence.nextId;
/**
 * Controlling groups of tweens
 *
 * Using the TWEEN singleton to manage your tweens can cause issues in large apps with many components.
 * In these cases, you may want to create your own smaller groups of tweens.
 */
var TWEEN = mainGroup;
// This is the best way to export things in a way that's compatible with both ES
// Modules and CommonJS, without build hacks, and so as not to break the
// existing API.
// https://github.com/rollup/rollup/issues/1961#issuecomment-423037881
var getAll = TWEEN.getAll.bind(TWEEN);
var removeAll = TWEEN.removeAll.bind(TWEEN);
var add = TWEEN.add.bind(TWEEN);
var remove = TWEEN.remove.bind(TWEEN);
var update = TWEEN.update.bind(TWEEN);
var exports = {
    Easing: Easing,
    Group: Group,
    Interpolation: Interpolation,
    now: now,
    Sequence: Sequence,
    nextId: nextId,
    Tween: Tween,
    VERSION: VERSION,
    getAll: getAll,
    removeAll: removeAll,
    add: add,
    remove: remove,
    update: update,
};

export { Easing, Group, Interpolation, Sequence, Tween, VERSION, add, exports as default, getAll, nextId, now, remove, removeAll, update };