@google/model-viewer/dist/model-viewer.js

Easily display interactive 3D models on the web and in AR!

/**
 * @license
 * Copyright 2019 Google LLC
 * SPDX-License-Identifier: BSD-3-Clause
 */
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/**
 * @license
 * Copyright 2017 Google LLC
 * SPDX-License-Identifier: BSD-3-Clause
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/**
 * @license
 * Copyright 2017 Google LLC
 * SPDX-License-Identifier: BSD-3-Clause
 */const o$1={attribute:true,type:String,converter:u$2,reflect:false,hasChanged:f$1},r$2=(t=o$1,e,r)=>{const{kind:n,metadata:i}=r;let s=globalThis.litPropertyMetadata.get(i);if(void 0===s&&globalThis.litPropertyMetadata.set(i,s=new Map),s.set(r.name,t),"accessor"===n){const{name:o}=r;return {set(r){const n=e.get.call(this);e.set.call(this,r),this.requestUpdate(o,n,t);},init(e){return void 0!==e&&this.P(o,void 0,t),e}}}if("setter"===n){const{name:o}=r;return function(r){const n=this[o];e.call(this,r),this.requestUpdate(o,n,t);}}throw Error("Unsupported decorator location: "+n)};function n$2(t){return (e,o)=>"object"==typeof o?r$2(t,e,o):((t,e,o)=>{const r=e.hasOwnProperty(o);return e.constructor.createProperty(o,r?{...t,wrapped:true}:t),r?Object.getOwnPropertyDescriptor(e,o):void 0})(t,e,o)}

/**
 * @license
 * Copyright 2010-2025 Three.js Authors
 * SPDX-License-Identifier: MIT
 */
const REVISION = '174';
const CullFaceNone = 0;
const CullFaceBack = 1;
const CullFaceFront = 2;
const PCFShadowMap = 1;
const PCFSoftShadowMap = 2;
const VSMShadowMap = 3;
const FrontSide = 0;
const BackSide = 1;
const DoubleSide = 2;
const NoBlending = 0;
const NormalBlending = 1;
const AdditiveBlending = 2;
const SubtractiveBlending = 3;
const MultiplyBlending = 4;
const CustomBlending = 5;
const AddEquation = 100;
const SubtractEquation = 101;
const ReverseSubtractEquation = 102;
const MinEquation = 103;
const MaxEquation = 104;
const ZeroFactor = 200;
const OneFactor = 201;
const SrcColorFactor = 202;
const OneMinusSrcColorFactor = 203;
const SrcAlphaFactor = 204;
const OneMinusSrcAlphaFactor = 205;
const DstAlphaFactor = 206;
const OneMinusDstAlphaFactor = 207;
const DstColorFactor = 208;
const OneMinusDstColorFactor = 209;
const SrcAlphaSaturateFactor = 210;
const ConstantColorFactor = 211;
const OneMinusConstantColorFactor = 212;
const ConstantAlphaFactor = 213;
const OneMinusConstantAlphaFactor = 214;
const NeverDepth = 0;
const AlwaysDepth = 1;
const LessDepth = 2;
const LessEqualDepth = 3;
const EqualDepth = 4;
const GreaterEqualDepth = 5;
const GreaterDepth = 6;
const NotEqualDepth = 7;
const MultiplyOperation = 0;
const MixOperation = 1;
const AddOperation = 2;
const NoToneMapping = 0;
const LinearToneMapping = 1;
const ReinhardToneMapping = 2;
const CineonToneMapping = 3;
const ACESFilmicToneMapping = 4;
const CustomToneMapping = 5;
const AgXToneMapping = 6;
const NeutralToneMapping = 7;
const AttachedBindMode = 'attached';
const DetachedBindMode = 'detached';

const UVMapping = 300;
const CubeReflectionMapping = 301;
const CubeRefractionMapping = 302;
const EquirectangularReflectionMapping = 303;
const EquirectangularRefractionMapping = 304;
const CubeUVReflectionMapping = 306;
const RepeatWrapping = 1000;
const ClampToEdgeWrapping = 1001;
const MirroredRepeatWrapping = 1002;
const NearestFilter = 1003;
const NearestMipmapNearestFilter = 1004;
const NearestMipmapLinearFilter = 1005;
const LinearFilter = 1006;
const LinearMipmapNearestFilter = 1007;
const LinearMipmapLinearFilter = 1008;
const LinearMipMapLinearFilter = 1008;
const UnsignedByteType = 1009;
const ByteType = 1010;
const ShortType = 1011;
const UnsignedShortType = 1012;
const IntType = 1013;
const UnsignedIntType = 1014;
const FloatType = 1015;
const HalfFloatType = 1016;
const UnsignedShort4444Type = 1017;
const UnsignedShort5551Type = 1018;
const UnsignedInt248Type = 1020;
const UnsignedInt5999Type = 35902;
const AlphaFormat = 1021;
const RGBFormat = 1022;
const RGBAFormat = 1023;
const LuminanceFormat = 1024;
const LuminanceAlphaFormat = 1025;
const DepthFormat = 1026;
const DepthStencilFormat = 1027;
const RedFormat = 1028;
const RedIntegerFormat = 1029;
const RGFormat = 1030;
const RGIntegerFormat = 1031;
const RGBAIntegerFormat = 1033;

const RGB_S3TC_DXT1_Format = 33776;
const RGBA_S3TC_DXT1_Format = 33777;
const RGBA_S3TC_DXT3_Format = 33778;
const RGBA_S3TC_DXT5_Format = 33779;
const RGB_PVRTC_4BPPV1_Format = 35840;
const RGB_PVRTC_2BPPV1_Format = 35841;
const RGBA_PVRTC_4BPPV1_Format = 35842;
const RGBA_PVRTC_2BPPV1_Format = 35843;
const RGB_ETC1_Format = 36196;
const RGB_ETC2_Format = 37492;
const RGBA_ETC2_EAC_Format = 37496;
const RGBA_ASTC_4x4_Format = 37808;
const RGBA_ASTC_5x4_Format = 37809;
const RGBA_ASTC_5x5_Format = 37810;
const RGBA_ASTC_6x5_Format = 37811;
const RGBA_ASTC_6x6_Format = 37812;
const RGBA_ASTC_8x5_Format = 37813;
const RGBA_ASTC_8x6_Format = 37814;
const RGBA_ASTC_8x8_Format = 37815;
const RGBA_ASTC_10x5_Format = 37816;
const RGBA_ASTC_10x6_Format = 37817;
const RGBA_ASTC_10x8_Format = 37818;
const RGBA_ASTC_10x10_Format = 37819;
const RGBA_ASTC_12x10_Format = 37820;
const RGBA_ASTC_12x12_Format = 37821;
const RGBA_BPTC_Format = 36492;
const RGB_BPTC_SIGNED_Format = 36494;
const RGB_BPTC_UNSIGNED_Format = 36495;
const RED_RGTC1_Format = 36283;
const SIGNED_RED_RGTC1_Format = 36284;
const RED_GREEN_RGTC2_Format = 36285;
const SIGNED_RED_GREEN_RGTC2_Format = 36286;
const LoopOnce = 2200;
const LoopRepeat = 2201;
const LoopPingPong = 2202;
const InterpolateDiscrete = 2300;
const InterpolateLinear = 2301;
const InterpolateSmooth = 2302;
const ZeroCurvatureEnding = 2400;
const ZeroSlopeEnding = 2401;
const WrapAroundEnding = 2402;
const NormalAnimationBlendMode = 2500;
const AdditiveAnimationBlendMode = 2501;
const TrianglesDrawMode = 0;
const TriangleStripDrawMode = 1;
const TriangleFanDrawMode = 2;
const BasicDepthPacking = 3200;
const RGBADepthPacking = 3201;
const TangentSpaceNormalMap = 0;
const ObjectSpaceNormalMap = 1;

// Color space string identifiers, matching CSS Color Module Level 4 and WebGPU names where available.
const NoColorSpace = '';
const SRGBColorSpace = 'srgb';
const LinearSRGBColorSpace = 'srgb-linear';

const LinearTransfer = 'linear';
const SRGBTransfer = 'srgb';
const KeepStencilOp = 7680;
const AlwaysStencilFunc = 519;

const NeverCompare = 512;
const LessCompare = 513;
const EqualCompare = 514;
const LessEqualCompare = 515;
const GreaterCompare = 516;
const NotEqualCompare = 517;
const GreaterEqualCompare = 518;
const AlwaysCompare = 519;

const StaticDrawUsage = 35044;
const GLSL3 = '300 es';

const WebGLCoordinateSystem = 2000;
const WebGPUCoordinateSystem = 2001;

/**
 * This modules allows to dispatch event objects on custom JavaScript objects.
 *
 * Main repository: [eventdispatcher.js]{@link https://github.com/mrdoob/eventdispatcher.js/}
 *
 * Code Example:
 * ```js
 * class Car extends EventDispatcher {
 * 	start() {
 *		this.dispatchEvent( { type: 'start', message: 'vroom vroom!' } );
 *	}
 *};
 *
 * // Using events with the custom object
 * const car = new Car();
 * car.addEventListener( 'start', function ( event ) {
 * 	alert( event.message );
 * } );
 *
 * car.start();
 * ```
 */
class EventDispatcher {

	/**
	 * Adds the given event listener to the given event type.
	 *
	 * @param {string} type - The type of event to listen to.
	 * @param {Function} listener - The function that gets called when the event is fired.
	 */
	addEventListener( type, listener ) {

		if ( this._listeners === undefined ) this._listeners = {};

		const listeners = this._listeners;

		if ( listeners[ type ] === undefined ) {

			listeners[ type ] = [];

		}

		if ( listeners[ type ].indexOf( listener ) === -1 ) {

			listeners[ type ].push( listener );

		}

	}

	/**
	 * Returns `true` if the given event listener has been added to the given event type.
	 *
	 * @param {string} type - The type of event.
	 * @param {Function} listener - The listener to check.
	 * @return {boolean} Whether the given event listener has been added to the given event type.
	 */
	hasEventListener( type, listener ) {

		const listeners = this._listeners;

		if ( listeners === undefined ) return false;

		return listeners[ type ] !== undefined && listeners[ type ].indexOf( listener ) !== -1;

	}

	/**
	 * Removes the given event listener from the given event type.
	 *
	 * @param {string} type - The type of event.
	 * @param {Function} listener - The listener to remove.
	 */
	removeEventListener( type, listener ) {

		const listeners = this._listeners;

		if ( listeners === undefined ) return;

		const listenerArray = listeners[ type ];

		if ( listenerArray !== undefined ) {

			const index = listenerArray.indexOf( listener );

			if ( index !== -1 ) {

				listenerArray.splice( index, 1 );

			}

		}

	}

	/**
	 * Dispatches an event object.
	 *
	 * @param {Object} event - The event that gets fired.
	 */
	dispatchEvent( event ) {

		const listeners = this._listeners;

		if ( listeners === undefined ) return;

		const listenerArray = listeners[ event.type ];

		if ( listenerArray !== undefined ) {

			event.target = this;

			// Make a copy, in case listeners are removed while iterating.
			const array = listenerArray.slice( 0 );

			for ( let i = 0, l = array.length; i < l; i ++ ) {

				array[ i ].call( this, event );

			}

			event.target = null;

		}

	}

}

const _lut = [ '00', '01', '02', '03', '04', '05', '06', '07', '08', '09', '0a', '0b', '0c', '0d', '0e', '0f', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '1a', '1b', '1c', '1d', '1e', '1f', '20', '21', '22', '23', '24', '25', '26', '27', '28', '29', '2a', '2b', '2c', '2d', '2e', '2f', '30', '31', '32', '33', '34', '35', '36', '37', '38', '39', '3a', '3b', '3c', '3d', '3e', '3f', '40', '41', '42', '43', '44', '45', '46', '47', '48', '49', '4a', '4b', '4c', '4d', '4e', '4f', '50', '51', '52', '53', '54', '55', '56', '57', '58', '59', '5a', '5b', '5c', '5d', '5e', '5f', '60', '61', '62', '63', '64', '65', '66', '67', '68', '69', '6a', '6b', '6c', '6d', '6e', '6f', '70', '71', '72', '73', '74', '75', '76', '77', '78', '79', '7a', '7b', '7c', '7d', '7e', '7f', '80', '81', '82', '83', '84', '85', '86', '87', '88', '89', '8a', '8b', '8c', '8d', '8e', '8f', '90', '91', '92', '93', '94', '95', '96', '97', '98', '99', '9a', '9b', '9c', '9d', '9e', '9f', 'a0', 'a1', 'a2', 'a3', 'a4', 'a5', 'a6', 'a7', 'a8', 'a9', 'aa', 'ab', 'ac', 'ad', 'ae', 'af', 'b0', 'b1', 'b2', 'b3', 'b4', 'b5', 'b6', 'b7', 'b8', 'b9', 'ba', 'bb', 'bc', 'bd', 'be', 'bf', 'c0', 'c1', 'c2', 'c3', 'c4', 'c5', 'c6', 'c7', 'c8', 'c9', 'ca', 'cb', 'cc', 'cd', 'ce', 'cf', 'd0', 'd1', 'd2', 'd3', 'd4', 'd5', 'd6', 'd7', 'd8', 'd9', 'da', 'db', 'dc', 'dd', 'de', 'df', 'e0', 'e1', 'e2', 'e3', 'e4', 'e5', 'e6', 'e7', 'e8', 'e9', 'ea', 'eb', 'ec', 'ed', 'ee', 'ef', 'f0', 'f1', 'f2', 'f3', 'f4', 'f5', 'f6', 'f7', 'f8', 'f9', 'fa', 'fb', 'fc', 'fd', 'fe', 'ff' ];

let _seed = 1234567;


const DEG2RAD = Math.PI / 180;
const RAD2DEG = 180 / Math.PI;

/**
 * Generate a [UUID]{@link https://en.wikipedia.org/wiki/Universally_unique_identifier}
 * (universally unique identifier).
 *
 * @return {string} The UUID.
 */
function generateUUID() {

	// http://stackoverflow.com/questions/105034/how-to-create-a-guid-uuid-in-javascript/21963136#21963136

	const d0 = Math.random() * 0xffffffff | 0;
	const d1 = Math.random() * 0xffffffff | 0;
	const d2 = Math.random() * 0xffffffff | 0;
	const d3 = Math.random() * 0xffffffff | 0;
	const uuid = _lut[ d0 & 0xff ] + _lut[ d0 >> 8 & 0xff ] + _lut[ d0 >> 16 & 0xff ] + _lut[ d0 >> 24 & 0xff ] + '-' +
			_lut[ d1 & 0xff ] + _lut[ d1 >> 8 & 0xff ] + '-' + _lut[ d1 >> 16 & 0x0f | 0x40 ] + _lut[ d1 >> 24 & 0xff ] + '-' +
			_lut[ d2 & 0x3f | 0x80 ] + _lut[ d2 >> 8 & 0xff ] + '-' + _lut[ d2 >> 16 & 0xff ] + _lut[ d2 >> 24 & 0xff ] +
			_lut[ d3 & 0xff ] + _lut[ d3 >> 8 & 0xff ] + _lut[ d3 >> 16 & 0xff ] + _lut[ d3 >> 24 & 0xff ];

	// .toLowerCase() here flattens concatenated strings to save heap memory space.
	return uuid.toLowerCase();

}

/**
 * Clamps the given value between min and max.
 *
 * @param {number} value - The value to clamp.
 * @param {number} min - The min value.
 * @param {number} max - The max value.
 * @return {number} The clamped value.
 */
function clamp$1( value, min, max ) {

	return Math.max( min, Math.min( max, value ) );

}

/**
 * Computes the Euclidean modulo of the given parameters that
 * is `( ( n % m ) + m ) % m`.
 *
 * @param {number} n - The first parameter.
 * @param {number} m - The second parameter.
 * @return {number} The Euclidean modulo.
 */
function euclideanModulo( n, m ) {

	// https://en.wikipedia.org/wiki/Modulo_operation

	return ( ( n % m ) + m ) % m;

}

/**
 * Performs a linear mapping from range `<a1, a2>` to range `<b1, b2>`
 * for the given value.
 *
 * @param {number} x - The value to be mapped.
 * @param {number} a1 - Minimum value for range A.
 * @param {number} a2 - Maximum value for range A.
 * @param {number} b1 - Minimum value for range B.
 * @param {number} b2 - Maximum value for range B.
 * @return {number} The mapped value.
 */
function mapLinear( x, a1, a2, b1, b2 ) {

	return b1 + ( x - a1 ) * ( b2 - b1 ) / ( a2 - a1 );

}

/**
 * Returns the percentage in the closed interval `[0, 1]` of the given value
 * between the start and end point.
 *
 * @param {number} x - The start point
 * @param {number} y - The end point.
 * @param {number} value - A value between start and end.
 * @return {number} The interpolation factor.
 */
function inverseLerp( x, y, value ) {

	// https://www.gamedev.net/tutorials/programming/general-and-gameplay-programming/inverse-lerp-a-super-useful-yet-often-overlooked-function-r5230/

	if ( x !== y ) {

		return ( value - x ) / ( y - x );

	} else {

		return 0;

	}

}

/**
 * Returns a value linearly interpolated from two known points based on the given interval -
 * `t = 0` will return `x` and `t = 1` will return `y`.
 *
 * @param {number} x - The start point
 * @param {number} y - The end point.
 * @param {number} t - The interpolation factor in the closed interval `[0, 1]`.
 * @return {number} The interpolated value.
 */
function lerp$1( x, y, t ) {

	return ( 1 - t ) * x + t * y;

}

/**
 * Smoothly interpolate a number from `x` to `y` in  a spring-like manner using a delta
 * time to maintain frame rate independent movement. For details, see
 * [Frame rate independent damping using lerp]{@link http://www.rorydriscoll.com/2016/03/07/frame-rate-independent-damping-using-lerp/}.
 *
 * @param {number} x - The current point.
 * @param {number} y - The target point.
 * @param {number} lambda - A higher lambda value will make the movement more sudden,
 * and a lower value will make the movement more gradual.
 * @param {number} dt - Delta time in seconds.
 * @return {number} The interpolated value.
 */
function damp( x, y, lambda, dt ) {

	return lerp$1( x, y, 1 - Math.exp( - lambda * dt ) );

}

/**
 * Returns a value that alternates between `0` and the given `length` parameter.
 *
 * @param {number} x - The value to pingpong.
 * @param {number} [length=1] - The positive value the function will pingpong to.
 * @return {number} The alternated value.
 */
function pingpong( x, length = 1 ) {

	// https://www.desmos.com/calculator/vcsjnyz7x4

	return length - Math.abs( euclideanModulo( x, length * 2 ) - length );

}

/**
 * Returns a value in the range `[0,1]` that represents the percentage that `x` has
 * moved between `min` and `max`, but smoothed or slowed down the closer `x` is to
 * the `min` and `max`.
 *
 * See [Smoothstep]{@link http://en.wikipedia.org/wiki/Smoothstep} for more details.
 *
 * @param {number} x - The value to evaluate based on its position between min and max.
 * @param {number} min - The min value. Any x value below min will be `0`.
 * @param {number} max - The max value. Any x value above max will be `1`.
 * @return {number} The alternated value.
 */
function smoothstep( x, min, max ) {

	if ( x <= min ) return 0;
	if ( x >= max ) return 1;

	x = ( x - min ) / ( max - min );

	return x * x * ( 3 - 2 * x );

}

/**
 * A [variation on smoothstep]{@link https://en.wikipedia.org/wiki/Smoothstep#Variations}
 * that has zero 1st and 2nd order derivatives at x=0 and x=1.
 *
 * @param {number} x - The value to evaluate based on its position between min and max.
 * @param {number} min - The min value. Any x value below min will be `0`.
 * @param {number} max - The max value. Any x value above max will be `1`.
 * @return {number} The alternated value.
 */
function smootherstep( x, min, max ) {

	if ( x <= min ) return 0;
	if ( x >= max ) return 1;

	x = ( x - min ) / ( max - min );

	return x * x * x * ( x * ( x * 6 - 15 ) + 10 );

}

/**
 * Returns a random integer from `<low, high>` interval.
 *
 * @param {number} low - The lower value boundary.
 * @param {number} high - The upper value boundary
 * @return {number} A random integer.
 */
function randInt( low, high ) {

	return low + Math.floor( Math.random() * ( high - low + 1 ) );

}

/**
 * Returns a random float from `<low, high>` interval.
 *
 * @param {number} low - The lower value boundary.
 * @param {number} high - The upper value boundary
 * @return {number} A random float.
 */
function randFloat( low, high ) {

	return low + Math.random() * ( high - low );

}

/**
 * Returns a random integer from `<-range/2, range/2>` interval.
 *
 * @param {number} range - Defines the value range.
 * @return {number} A random float.
 */
function randFloatSpread( range ) {

	return range * ( 0.5 - Math.random() );

}

/**
 * Returns a deterministic pseudo-random float in the interval `[0, 1]`.
 *
 * @param {number} [s] - The integer seed.
 * @return {number} A random float.
 */
function seededRandom( s ) {

	if ( s !== undefined ) _seed = s;

	// Mulberry32 generator

	let t = _seed += 0x6D2B79F5;

	t = Math.imul( t ^ t >>> 15, t | 1 );

	t ^= t + Math.imul( t ^ t >>> 7, t | 61 );

	return ( ( t ^ t >>> 14 ) >>> 0 ) / 4294967296;

}

/**
 * Converts degrees to radians.
 *
 * @param {number} degrees - A value in degrees.
 * @return {number} The converted value in radians.
 */
function degToRad( degrees ) {

	return degrees * DEG2RAD;

}

/**
 * Converts radians to degrees.
 *
 * @param {number} radians - A value in radians.
 * @return {number} The converted value in degrees.
 */
function radToDeg( radians ) {

	return radians * RAD2DEG;

}

/**
 * Returns `true` if the given number is a power of two.
 *
 * @param {number} value - The value to check.
 * @return {boolean} Whether the given number is a power of two or not.
 */
function isPowerOfTwo( value ) {

	return ( value & ( value - 1 ) ) === 0 && value !== 0;

}

/**
 * Returns the smallest power of two that is greater than or equal to the given number.
 *
 * @param {number} value - The value to find a POT for.
 * @return {number} The smallest power of two that is greater than or equal to the given number.
 */
function ceilPowerOfTwo( value ) {

	return Math.pow( 2, Math.ceil( Math.log( value ) / Math.LN2 ) );

}

/**
 * Returns the largest power of two that is less than or equal to the given number.
 *
 * @param {number} value - The value to find a POT for.
 * @return {number} The largest power of two that is less than or equal to the given number.
 */
function floorPowerOfTwo( value ) {

	return Math.pow( 2, Math.floor( Math.log( value ) / Math.LN2 ) );

}

/**
 * Sets the given quaternion from the [Intrinsic Proper Euler Angles]{@link https://en.wikipedia.org/wiki/Euler_angles}
 * defined by the given angles and order.
 *
 * Rotations are applied to the axes in the order specified by order:
 * rotation by angle `a` is applied first, then by angle `b`, then by angle `c`.
 *
 * @param {Quaternion} q - The quaternion to set.
 * @param {number} a - The rotation applied to the first axis, in radians.
 * @param {number} b - The rotation applied to the second axis, in radians.
 * @param {number} c - The rotation applied to the third axis, in radians.
 * @param {('XYX'|'XZX'|'YXY'|'YZY'|'ZXZ'|'ZYZ')} order - A string specifying the axes order.
 */
function setQuaternionFromProperEuler( q, a, b, c, order ) {

	const cos = Math.cos;
	const sin = Math.sin;

	const c2 = cos( b / 2 );
	const s2 = sin( b / 2 );

	const c13 = cos( ( a + c ) / 2 );
	const s13 = sin( ( a + c ) / 2 );

	const c1_3 = cos( ( a - c ) / 2 );
	const s1_3 = sin( ( a - c ) / 2 );

	const c3_1 = cos( ( c - a ) / 2 );
	const s3_1 = sin( ( c - a ) / 2 );

	switch ( order ) {

		case 'XYX':
			q.set( c2 * s13, s2 * c1_3, s2 * s1_3, c2 * c13 );
			break;

		case 'YZY':
			q.set( s2 * s1_3, c2 * s13, s2 * c1_3, c2 * c13 );
			break;

		case 'ZXZ':
			q.set( s2 * c1_3, s2 * s1_3, c2 * s13, c2 * c13 );
			break;

		case 'XZX':
			q.set( c2 * s13, s2 * s3_1, s2 * c3_1, c2 * c13 );
			break;

		case 'YXY':
			q.set( s2 * c3_1, c2 * s13, s2 * s3_1, c2 * c13 );
			break;

		case 'ZYZ':
			q.set( s2 * s3_1, s2 * c3_1, c2 * s13, c2 * c13 );
			break;

		default:
			console.warn( 'THREE.MathUtils: .setQuaternionFromProperEuler() encountered an unknown order: ' + order );

	}

}

/**
 * Denormalizes the given value according to the given typed array.
 *
 * @param {number} value - The value to denormalize.
 * @param {TypedArray} array - The typed array that defines the data type of the value.
 * @return {number} The denormalize (float) value in the range `[0,1]`.
 */
function denormalize( value, array ) {

	switch ( array.constructor ) {

		case Float32Array:

			return value;

		case Uint32Array:

			return value / 4294967295.0;

		case Uint16Array:

			return value / 65535.0;

		case Uint8Array:

			return value / 255.0;

		case Int32Array:

			return Math.max( value / 2147483647.0, -1 );

		case Int16Array:

			return Math.max( value / 32767.0, -1 );

		case Int8Array:

			return Math.max( value / 127.0, -1 );

		default:

			throw new Error( 'Invalid component type.' );

	}

}

/**
 * Normalizes the given value according to the given typed array.
 *
 * @param {number} value - The float value in the range `[0,1]` to normalize.
 * @param {TypedArray} array - The typed array that defines the data type of the value.
 * @return {number} The normalize value.
 */
function normalize( value, array ) {

	switch ( array.constructor ) {

		case Float32Array:

			return value;

		case Uint32Array:

			return Math.round( value * 4294967295.0 );

		case Uint16Array:

			return Math.round( value * 65535.0 );

		case Uint8Array:

			return Math.round( value * 255.0 );

		case Int32Array:

			return Math.round( value * 2147483647.0 );

		case Int16Array:

			return Math.round( value * 32767.0 );

		case Int8Array:

			return Math.round( value * 127.0 );

		default:

			throw new Error( 'Invalid component type.' );

	}

}

const MathUtils = {
	DEG2RAD: DEG2RAD,
	RAD2DEG: RAD2DEG,
	generateUUID: generateUUID,
	clamp: clamp$1,
	euclideanModulo: euclideanModulo,
	mapLinear: mapLinear,
	inverseLerp: inverseLerp,
	lerp: lerp$1,
	damp: damp,
	pingpong: pingpong,
	smoothstep: smoothstep,
	smootherstep: smootherstep,
	randInt: randInt,
	randFloat: randFloat,
	randFloatSpread: randFloatSpread,
	seededRandom: seededRandom,
	degToRad: degToRad,
	radToDeg: radToDeg,
	isPowerOfTwo: isPowerOfTwo,
	ceilPowerOfTwo: ceilPowerOfTwo,
	floorPowerOfTwo: floorPowerOfTwo,
	setQuaternionFromProperEuler: setQuaternionFromProperEuler,
	normalize: normalize,
	denormalize: denormalize
};

/**
 * Class representing a 2D vector. A 2D vector is an ordered pair of numbers
 * (labeled x and y), which can be used to represent a number of things, such as:
 *
 * - A point in 2D space (i.e. a position on a plane).
 * - A direction and length across a plane. In three.js the length will
 * always be the Euclidean distance(straight-line distance) from `(0, 0)` to `(x, y)`
 * and the direction is also measured from `(0, 0)` towards `(x, y)`.
 * - Any arbitrary ordered pair of numbers.
 *
 * There are other things a 2D vector can be used to represent, such as
 * momentum vectors, complex numbers and so on, however these are the most
 * common uses in three.js.
 *
 * Iterating through a vector instance will yield its components `(x, y)` in
 * the corresponding order.
 * ```js
 * const a = new THREE.Vector2( 0, 1 );
 *
 * //no arguments; will be initialised to (0, 0)
 * const b = new THREE.Vector2( );
 *
 * const d = a.distanceTo( b );
 * ```
 */
class Vector2 {

	/**
	 * Constructs a new 2D vector.
	 *
	 * @param {number} [x=0] - The x value of this vector.
	 * @param {number} [y=0] - The y value of this vector.
	 */
	constructor( x = 0, y = 0 ) {

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		Vector2.prototype.isVector2 = true;

		/**
		 * The x value of this vector.
		 *
		 * @type {number}
		 */
		this.x = x;

		/**
		 * The y value of this vector.
		 *
		 * @type {number}
		 */
		this.y = y;

	}

	/**
	 * Alias for {@link Vector2#x}.
	 *
	 * @type {number}
	 */
	get width() {

		return this.x;

	}

	set width( value ) {

		this.x = value;

	}

	/**
	 * Alias for {@link Vector2#y}.
	 *
	 * @type {number}
	 */
	get height() {

		return this.y;

	}

	set height( value ) {

		this.y = value;

	}

	/**
	 * Sets the vector components.
	 *
	 * @param {number} x - The value of the x component.
	 * @param {number} y - The value of the y component.
	 * @return {Vector2} A reference to this vector.
	 */
	set( x, y ) {

		this.x = x;
		this.y = y;

		return this;

	}

	/**
	 * Sets the vector components to the same value.
	 *
	 * @param {number} scalar - The value to set for all vector components.
	 * @return {Vector2} A reference to this vector.
	 */
	setScalar( scalar ) {

		this.x = scalar;
		this.y = scalar;

		return this;

	}

	/**
	 * Sets the vector's x component to the given value
	 *
	 * @param {number} x - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setX( x ) {

		this.x = x;

		return this;

	}

	/**
	 * Sets the vector's y component to the given value
	 *
	 * @param {number} y - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setY( y ) {

		this.y = y;

		return this;

	}

	/**
	 * Allows to set a vector component with an index.
	 *
	 * @param {number} index - The component index. `0` equals to x, `1` equals to y.
	 * @param {number} value - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setComponent( index, value ) {

		switch ( index ) {

			case 0: this.x = value; break;
			case 1: this.y = value; break;
			default: throw new Error( 'index is out of range: ' + index );

		}

		return this;

	}

	/**
	 * Returns the value of the vector component which matches the given index.
	 *
	 * @param {number} index - The component index. `0` equals to x, `1` equals to y.
	 * @return {number} A vector component value.
	 */
	getComponent( index ) {

		switch ( index ) {

			case 0: return this.x;
			case 1: return this.y;
			default: throw new Error( 'index is out of range: ' + index );

		}

	}

	/**
	 * Returns a new vector with copied values from this instance.
	 *
	 * @return {Vector2} A clone of this instance.
	 */
	clone() {

		return new this.constructor( this.x, this.y );

	}

	/**
	 * Copies the values of the given vector to this instance.
	 *
	 * @param {Vector2} v - The vector to copy.
	 * @return {Vector2} A reference to this vector.
	 */
	copy( v ) {

		this.x = v.x;
		this.y = v.y;

		return this;

	}

	/**
	 * Adds the given vector to this instance.
	 *
	 * @param {Vector2} v - The vector to add.
	 * @return {Vector2} A reference to this vector.
	 */
	add( v ) {

		this.x += v.x;
		this.y += v.y;

		return this;

	}

	/**
	 * Adds the given scalar value to all components of this instance.
	 *
	 * @param {number} s - The scalar to add.
	 * @return {Vector2} A reference to this vector.
	 */
	addScalar( s ) {

		this.x += s;
		this.y += s;

		return this;

	}

	/**
	 * Adds the given vectors and stores the result in this instance.
	 *
	 * @param {Vector2} a - The first vector.
	 * @param {Vector2} b - The second vector.
	 * @return {Vector2} A reference to this vector.
	 */
	addVectors( a, b ) {

		this.x = a.x + b.x;
		this.y = a.y + b.y;

		return this;

	}

	/**
	 * Adds the given vector scaled by the given factor to this instance.
	 *
	 * @param {Vector2} v - The vector.
	 * @param {number} s - The factor that scales `v`.
	 * @return {Vector2} A reference to this vector.
	 */
	addScaledVector( v, s ) {

		this.x += v.x * s;
		this.y += v.y * s;

		return this;

	}

	/**
	 * Subtracts the given vector from this instance.
	 *
	 * @param {Vector2} v - The vector to subtract.
	 * @return {Vector2} A reference to this vector.
	 */
	sub( v ) {

		this.x -= v.x;
		this.y -= v.y;

		return this;

	}

	/**
	 * Subtracts the given scalar value from all components of this instance.
	 *
	 * @param {number} s - The scalar to subtract.
	 * @return {Vector2} A reference to this vector.
	 */
	subScalar( s ) {

		this.x -= s;
		this.y -= s;

		return this;

	}

	/**
	 * Subtracts the given vectors and stores the result in this instance.
	 *
	 * @param {Vector2} a - The first vector.
	 * @param {Vector2} b - The second vector.
	 * @return {Vector2} A reference to this vector.
	 */
	subVectors( a, b ) {

		this.x = a.x - b.x;
		this.y = a.y - b.y;

		return this;

	}

	/**
	 * Multiplies the given vector with this instance.
	 *
	 * @param {Vector2} v - The vector to multiply.
	 * @return {Vector2} A reference to this vector.
	 */
	multiply( v ) {

		this.x *= v.x;
		this.y *= v.y;

		return this;

	}

	/**
	 * Multiplies the given scalar value with all components of this instance.
	 *
	 * @param {number} scalar - The scalar to multiply.
	 * @return {Vector2} A reference to this vector.
	 */
	multiplyScalar( scalar ) {

		this.x *= scalar;
		this.y *= scalar;

		return this;

	}

	/**
	 * Divides this instance by the given vector.
	 *
	 * @param {Vector2} v - The vector to divide.
	 * @return {Vector2} A reference to this vector.
	 */
	divide( v ) {

		this.x /= v.x;
		this.y /= v.y;

		return this;

	}

	/**
	 * Divides this vector by the given scalar.
	 *
	 * @param {number} scalar - The scalar to divide.
	 * @return {Vector2} A reference to this vector.
	 */
	divideScalar( scalar ) {

		return this.multiplyScalar( 1 / scalar );

	}

	/**
	 * Multiplies this vector (with an implicit 1 as the 3rd component) by
	 * the given 3x3 matrix.
	 *
	 * @param {Matrix3} m - The matrix to apply.
	 * @return {Vector2} A reference to this vector.
	 */
	applyMatrix3( m ) {

		const x = this.x, y = this.y;
		const e = m.elements;

		this.x = e[ 0 ] * x + e[ 3 ] * y + e[ 6 ];
		this.y = e[ 1 ] * x + e[ 4 ] * y + e[ 7 ];

		return this;

	}

	/**
	 * If this vector's x or y value is greater than the given vector's x or y
	 * value, replace that value with the corresponding min value.
	 *
	 * @param {Vector2} v - The vector.
	 * @return {Vector2} A reference to this vector.
	 */
	min( v ) {

		this.x = Math.min( this.x, v.x );
		this.y = Math.min( this.y, v.y );

		return this;

	}

	/**
	 * If this vector's x or y value is less than the given vector's x or y
	 * value, replace that value with the corresponding max value.
	 *
	 * @param {Vector2} v - The vector.
	 * @return {Vector2} A reference to this vector.
	 */
	max( v ) {

		this.x = Math.max( this.x, v.x );
		this.y = Math.max( this.y, v.y );

		return this;

	}

	/**
	 * If this vector's x or y value is greater than the max vector's x or y
	 * value, it is replaced by the corresponding value.
	 * If this vector's x or y value is less than the min vector's x or y value,
	 * it is replaced by the corresponding value.
	 *
	 * @param {Vector2} min - The minimum x and y values.
	 * @param {Vector2} max - The maximum x and y values in the desired range.
	 * @return {Vector2} A reference to this vector.
	 */
	clamp( min, max ) {

		// assumes min < max, componentwise

		this.x = clamp$1( this.x, min.x, max.x );
		this.y = clamp$1( this.y, min.y, max.y );

		return this;

	}

	/**
	 * If this vector's x or y values are greater than the max value, they are
	 * replaced by the max value.
	 * If this vector's x or y values are less than the min value, they are
	 * replaced by the min value.
	 *
	 * @param {number} minVal - The minimum value the components will be clamped to.
	 * @param {number} maxVal - The maximum value the components will be clamped to.
	 * @return {Vector2} A reference to this vector.
	 */
	clampScalar( minVal, maxVal ) {

		this.x = clamp$1( this.x, minVal, maxVal );
		this.y = clamp$1( this.y, minVal, maxVal );

		return this;

	}

	/**
	 * If this vector's length is greater than the max value, it is replaced by
	 * the max value.
	 * If this vector's length is less than the min value, it is replaced by the
	 * min value.
	 *
	 * @param {number} min - The minimum value the vector length will be clamped to.
	 * @param {number} max - The maximum value the vector length will be clamped to.
	 * @return {Vector2} A reference to this vector.
	 */
	clampLength( min, max ) {

		const length = this.length();

		return this.divideScalar( length || 1 ).multiplyScalar( clamp$1( length, min, max ) );

	}

	/**
	 * The components of this vector are rounded down to the nearest integer value.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	floor() {

		this.x = Math.floor( this.x );
		this.y = Math.floor( this.y );

		return this;

	}

	/**
	 * The components of this vector are rounded up to the nearest integer value.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	ceil() {

		this.x = Math.ceil( this.x );
		this.y = Math.ceil( this.y );

		return this;

	}

	/**
	 * The components of this vector are rounded to the nearest integer value
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	round() {

		this.x = Math.round( this.x );
		this.y = Math.round( this.y );

		return this;

	}

	/**
	 * The components of this vector are rounded towards zero (up if negative,
	 * down if positive) to an integer value.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	roundToZero() {

		this.x = Math.trunc( this.x );
		this.y = Math.trunc( this.y );

		return this;

	}

	/**
	 * Inverts this vector - i.e. sets x = -x and y = -y.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	negate() {

		this.x = - this.x;
		this.y = - this.y;

		return this;

	}

	/**
	 * Calculates the dot product of the given vector with this instance.
	 *
	 * @param {Vector2} v - The vector to compute the dot product with.
	 * @return {number} The result of the dot product.
	 */
	dot( v ) {

		return this.x * v.x + this.y * v.y;

	}

	/**
	 * Calculates the cross product of the given vector with this instance.
	 *
	 * @param {Vector2} v - The vector to compute the cross product with.
	 * @return {number} The result of the cross product.
	 */
	cross( v ) {

		return this.x * v.y - this.y * v.x;

	}

	/**
	 * Computes the square of the Euclidean length (straight-line length) from
	 * (0, 0) to (x, y). If you are comparing the lengths of vectors, you should
	 * compare the length squared instead as it is slightly more efficient to calculate.
	 *
	 * @return {number} The square length of this vector.
	 */
	lengthSq() {

		return this.x * this.x + this.y * this.y;

	}

	/**
	 * Computes the  Euclidean length (straight-line length) from (0, 0) to (x, y).
	 *
	 * @return {number} The length of this vector.
	 */
	length() {

		return Math.sqrt( this.x * this.x + this.y * this.y );

	}

	/**
	 * Computes the Manhattan length of this vector.
	 *
	 * @return {number} The length of this vector.
	 */
	manhattanLength() {

		return Math.abs( this.x ) + Math.abs( this.y );

	}

	/**
	 * Converts this vector to a unit vector - that is, sets it equal to a vector
	 * with the same direction as this one, but with a vector length of `1`.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	normalize() {

		return this.divideScalar( this.length() || 1 );

	}

	/**
	 * Computes the angle in radians of this vector with respect to the positive x-axis.
	 *
	 * @return {number} The angle in radians.
	 */
	angle() {

		const angle = Math.atan2( - this.y, - this.x ) + Math.PI;

		return angle;

	}

	/**
	 * Returns the angle between the given vector and this instance in radians.
	 *
	 * @param {Vector2} v - The vector to compute the angle with.
	 * @return {number} The angle in radians.
	 */
	angleTo( v ) {

		const denominator = Math.sqrt( this.lengthSq() * v.lengthSq() );

		if ( denominator === 0 ) return Math.PI / 2;

		const theta = this.dot( v ) / denominator;

		// clamp, to handle numerical problems

		return Math.acos( clamp$1( theta, -1, 1 ) );

	}

	/**
	 * Computes the distance from the given vector to this instance.
	 *
	 * @param {Vector2} v - The vector to compute the distance to.
	 * @return {number} The distance.
	 */
	distanceTo( v ) {

		return Math.sqrt( this.distanceToSquared( v ) );

	}

	/**
	 * Computes the squared distance from the given vector to this instance.
	 * If you are just comparing the distance with another distance, you should compare
	 * the distance squared instead as it is slightly more efficient to calculate.
	 *
	 * @param {Vector2} v - The vector to compute the squared distance to.
	 * @return {number} The squared distance.
	 */
	distanceToSquared( v ) {

		const dx = this.x - v.x, dy = this.y - v.y;
		return dx * dx + dy * dy;

	}

	/**
	 * Computes the Manhattan distance from the given vector to this instance.
	 *
	 * @param {Vector2} v - The vector to compute the Manhattan distance to.
	 * @return {number} The Manhattan distance.
	 */
	manhattanDistanceTo( v ) {

		return Math.abs( this.x - v.x ) + Math.abs( this.y - v.y );

	}

	/**
	 * Sets this vector to a vector with the same direction as this one, but
	 * with the specified length.
	 *
	 * @param {number} length - The new length of this vector.
	 * @return {Vector2} A reference to this vector.
	 */
	setLength( length ) {

		return this.normalize().multiplyScalar( length );

	}

	/**
	 * Linearly interpolates between the given vector and this instance, where
	 * alpha is the percent distance along the line - alpha = 0 will be this
	 * vector, and alpha = 1 will be the given one.
	 *
	 * @param {Vector2} v - The vector to interpolate towards.
	 * @param {number} alpha - The interpolation factor, typically in the closed interval `[0, 1]`.
	 * @return {Vector2} A reference to this vector.
	 */
	lerp( v, alpha ) {

		this.x += ( v.x - this.x ) * alpha;
		this.y += ( v.y - this.y ) * alpha;

		return this;

	}

	/**
	 * Linearly interpolates between the given vectors, where alpha is the percent
	 * distance along the line - alpha = 0 will be first vector, and alpha = 1 will
	 * be the second one. The result is stored in this instance.
	 *
	 * @param {Vector2} v1 - The first vector.
	 * @param {Vector2} v2 - The second vector.
	 * @param {number} alpha - The interpolation factor, typically in the closed interval `[0, 1]`.
	 * @return {Vector2} A reference to this vector.
	 */
	lerpVectors( v1, v2, alpha ) {

		this.x = v1.x + ( v2.x - v1.x ) * alpha;
		this.y = v1.y + ( v2.y - v1.y ) * alpha;

		return this;

	}

	/**
	 * Returns `true` if this vector is equal with the given one.
	 *
	 * @param {Vector2} v - The vector to test for equality.
	 * @return {boolean} Whether this vector is equal with the given one.
	 */
	equals( v ) {

		return ( ( v.x === this.x ) && ( v.y === this.y ) );

	}

	/**
	 * Sets this vector's x value to be `array[ offset ]` and y
	 * value to be `array[ offset + 1 ]`.
	 *
	 * @param {Array<number>} array - An array holding the vector component values.
	 * @param {number} [offset=0] - The offset into the array.
	 * @return {Vector2} A reference to this vector.
	 */
	fromArray( array, offset = 0 ) {

		this.x = array[ offset ];
		this.y = array[ offset + 1 ];

		return this;

	}

	/**
	 * Writes the components of this vector to the given array. If no array is provided,
	 * the method returns a new instance.
	 *
	 * @param {Array<number>} [array=[]] - The target array holding the vector components.
	 * @param {number} [offset=0] - Index of the first element in the array.
	 * @return {Array<number>} The vector components.
	 */
	toArray( array = [], offset = 0 ) {

		array[ offset ] = this.x;
		array[ offset + 1 ] = this.y;

		return array;

	}

	/**
	 * Sets the components of this vector from the given buffer attribute.
	 *
	 * @param {BufferAttribute} attribute - The buffer attribute holding vector data.
	 * @param {number} index - The index into the attribute.
	 * @return {Vector2} A reference to this vector.
	 */
	fromBufferAttribute( attribute, index ) {

		this.x = attribute.getX( index );
		this.y = attribute.getY( index );

		return this;

	}

	/**
	 * Rotates this vector around the given center by the given angle.
	 *
	 * @param {Vector2} center - The point around which to rotate.
	 * @param {number} angle - The angle to rotate, in radians.
	 * @return {Vector2} A reference to this vector.
	 */
	rotateAround( center, angle ) {

		const c = Math.cos( angle ), s = Math.sin( angle );

		const x = this.x - center.x;
		const y = this.y - center.y;

		this.x = x * c - y * s + center.x;
		this.y = x * s + y * c + center.y;

		return this;

	}

	/**
	 * Sets each component of this vector to a pseudo-random value between `0` and
	 * `1`, excluding `1`.
	 *
	 * @return {Vector2} A reference to this vector.
	 */
	random() {

		this.x = Math.random();
		this.y = Math.random();

		return this;

	}

	*[ Symbol.iterator ]() {

		yield this.x;
		yield this.y;

	}

}

/**
 * Represents a 3x3 matrix.
 *
 * A Note on Row-Major and Column-Major Ordering:
 *
 * The constructor and {@link Matrix3#set} method take arguments in
 * [row-major]{@link https://en.wikipedia.org/wiki/Row-_and_column-major_order#Column-major_order}
 * order, while internally they are stored in the {@link Matrix3#elements} array in column-major order.
 * This means that calling:
 * ```js
 * const m = new THREE.Matrix();
 * m.set( 11, 12, 13,
 *        21, 22, 23,
 *        31, 32, 33 );
 * ```
 * will result in the elements array containing:
 * ```js
 * m.elements = [ 11, 21, 31,
 *                12, 22, 32,
 *                13, 23, 33 ];
 * ```
 * and internally all calculations are performed using column-major ordering.
 * However, as the actual ordering makes no difference mathematically and
 * most people are used to thinking about matrices in row-major order, the
 * three.js documentation shows matrices in row-major order. Just bear in
 * mind that if you are reading the source code, you'll have to take the
 * transpose of any matrices outlined here to make sense of the calculations.
 */
class Matrix3 {

	/**
	 * Constructs a new 3x3 matrix. The arguments are supposed to be
	 * in row-major order. If no arguments are provided, the constructor
	 * initializes the matrix as an identity matrix.
	 *
	 * @param {number} [n11] - 1-1 matrix element.
	 * @param {number} [n12] - 1-2 matrix element.
	 * @param {number} [n13] - 1-3 matrix element.
	 * @param {number} [n21] - 2-1 matrix element.
	 * @param {number} [n22] - 2-2 matrix element.
	 * @param {number} [n23] - 2-3 matrix element.
	 * @param {number} [n31] - 3-1 matrix element.
	 * @param {number} [n32] - 3-2 matrix element.
	 * @param {number} [n33] - 3-3 matrix element.
	 */
	constructor(