three-stdlib/loaders/GLTFLoader.cjs.map

stand-alone library of threejs examples

{"version":3,"file":"GLTFLoader.cjs","sources":["../../src/loaders/GLTFLoader.js"],"sourcesContent":["import {\n  AnimationClip,\n  Bone,\n  Box3,\n  BufferAttribute,\n  BufferGeometry,\n  ClampToEdgeWrapping,\n  Color,\n  DirectionalLight,\n  DoubleSide,\n  FileLoader,\n  FrontSide,\n  Group,\n  ImageBitmapLoader,\n  InstancedMesh,\n  InterleavedBuffer,\n  InterleavedBufferAttribute,\n  Interpolant,\n  InterpolateDiscrete,\n  InterpolateLinear,\n  Line,\n  LineBasicMaterial,\n  LineLoop,\n  LineSegments,\n  LinearFilter,\n  LinearMipmapLinearFilter,\n  LinearMipmapNearestFilter,\n  Loader,\n  LoaderUtils,\n  Material,\n  MathUtils,\n  Matrix4,\n  Mesh,\n  MeshBasicMaterial,\n  MeshPhysicalMaterial,\n  MeshStandardMaterial,\n  MirroredRepeatWrapping,\n  NearestFilter,\n  NearestMipmapLinearFilter,\n  NearestMipmapNearestFilter,\n  NumberKeyframeTrack,\n  Object3D,\n  OrthographicCamera,\n  PerspectiveCamera,\n  PointLight,\n  Points,\n  PointsMaterial,\n  PropertyBinding,\n  Quaternion,\n  QuaternionKeyframeTrack,\n  RepeatWrapping,\n  Skeleton,\n  SkinnedMesh,\n  Sphere,\n  SpotLight,\n  Texture,\n  TextureLoader,\n  TriangleFanDrawMode,\n  TriangleStripDrawMode,\n  Vector2,\n  Vector3,\n  VectorKeyframeTrack,\n  InstancedBufferAttribute,\n} from 'three'\nimport { toTrianglesDrawMode } from '../utils/BufferGeometryUtils'\nimport { version } from '../_polyfill/constants'\nimport { decodeText } from '../_polyfill/LoaderUtils'\n\nconst SRGBColorSpace = 'srgb'\nconst LinearSRGBColorSpace = 'srgb-linear'\nconst sRGBEncoding = 3001\nconst LinearEncoding = 3000\n\nclass GLTFLoader extends Loader {\n  constructor(manager) {\n    super(manager)\n\n    this.dracoLoader = null\n    this.ktx2Loader = null\n    this.meshoptDecoder = null\n\n    this.pluginCallbacks = []\n\n    this.register(function (parser) {\n      return new GLTFMaterialsClearcoatExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsDispersionExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFTextureBasisUExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFTextureWebPExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFTextureAVIFExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsSheenExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsTransmissionExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsVolumeExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsIorExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsEmissiveStrengthExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsSpecularExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsIridescenceExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsAnisotropyExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMaterialsBumpExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFLightsExtension(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMeshoptCompression(parser)\n    })\n\n    this.register(function (parser) {\n      return new GLTFMeshGpuInstancing(parser)\n    })\n  }\n\n  load(url, onLoad, onProgress, onError) {\n    const scope = this\n\n    let resourcePath\n\n    if (this.resourcePath !== '') {\n      resourcePath = this.resourcePath\n    } else if (this.path !== '') {\n      // If a base path is set, resources will be relative paths from that plus the relative path of the gltf file\n      // Example  path = 'https://my-cnd-server.com/', url = 'assets/models/model.gltf'\n      // resourcePath = 'https://my-cnd-server.com/assets/models/'\n      // referenced resource 'model.bin' will be loaded from 'https://my-cnd-server.com/assets/models/model.bin'\n      // referenced resource '../textures/texture.png' will be loaded from 'https://my-cnd-server.com/assets/textures/texture.png'\n      const relativeUrl = LoaderUtils.extractUrlBase(url)\n      resourcePath = LoaderUtils.resolveURL(relativeUrl, this.path)\n    } else {\n      resourcePath = LoaderUtils.extractUrlBase(url)\n    }\n\n    // Tells the LoadingManager to track an extra item, which resolves after\n    // the model is fully loaded. This means the count of items loaded will\n    // be incorrect, but ensures manager.onLoad() does not fire early.\n    this.manager.itemStart(url)\n\n    const _onError = function (e) {\n      if (onError) {\n        onError(e)\n      } else {\n        console.error(e)\n      }\n\n      scope.manager.itemError(url)\n      scope.manager.itemEnd(url)\n    }\n\n    const loader = new FileLoader(this.manager)\n\n    loader.setPath(this.path)\n    loader.setResponseType('arraybuffer')\n    loader.setRequestHeader(this.requestHeader)\n    loader.setWithCredentials(this.withCredentials)\n\n    loader.load(\n      url,\n      function (data) {\n        try {\n          scope.parse(\n            data,\n            resourcePath,\n            function (gltf) {\n              onLoad(gltf)\n\n              scope.manager.itemEnd(url)\n            },\n            _onError,\n          )\n        } catch (e) {\n          _onError(e)\n        }\n      },\n      onProgress,\n      _onError,\n    )\n  }\n\n  setDRACOLoader(dracoLoader) {\n    this.dracoLoader = dracoLoader\n    return this\n  }\n\n  setDDSLoader() {\n    throw new Error('THREE.GLTFLoader: \"MSFT_texture_dds\" no longer supported. Please update to \"KHR_texture_basisu\".')\n  }\n\n  setKTX2Loader(ktx2Loader) {\n    this.ktx2Loader = ktx2Loader\n    return this\n  }\n\n  setMeshoptDecoder(meshoptDecoder) {\n    this.meshoptDecoder = meshoptDecoder\n    return this\n  }\n\n  register(callback) {\n    if (this.pluginCallbacks.indexOf(callback) === -1) {\n      this.pluginCallbacks.push(callback)\n    }\n\n    return this\n  }\n\n  unregister(callback) {\n    if (this.pluginCallbacks.indexOf(callback) !== -1) {\n      this.pluginCallbacks.splice(this.pluginCallbacks.indexOf(callback), 1)\n    }\n\n    return this\n  }\n\n  parse(data, path, onLoad, onError) {\n    let json\n    const extensions = {}\n    const plugins = {}\n\n    if (typeof data === 'string') {\n      json = JSON.parse(data)\n    } else if (data instanceof ArrayBuffer) {\n      const magic = decodeText(new Uint8Array(data.slice(0, 4)))\n\n      if (magic === BINARY_EXTENSION_HEADER_MAGIC) {\n        try {\n          extensions[EXTENSIONS.KHR_BINARY_GLTF] = new GLTFBinaryExtension(data)\n        } catch (error) {\n          if (onError) onError(error)\n          return\n        }\n\n        json = JSON.parse(extensions[EXTENSIONS.KHR_BINARY_GLTF].content)\n      } else {\n        json = JSON.parse(decodeText(new Uint8Array(data)))\n      }\n    } else {\n      json = data\n    }\n\n    if (json.asset === undefined || json.asset.version[0] < 2) {\n      if (onError) onError(new Error('THREE.GLTFLoader: Unsupported asset. glTF versions >=2.0 are supported.'))\n      return\n    }\n\n    const parser = new GLTFParser(json, {\n      path: path || this.resourcePath || '',\n      crossOrigin: this.crossOrigin,\n      requestHeader: this.requestHeader,\n      manager: this.manager,\n      ktx2Loader: this.ktx2Loader,\n      meshoptDecoder: this.meshoptDecoder,\n    })\n\n    parser.fileLoader.setRequestHeader(this.requestHeader)\n\n    for (let i = 0; i < this.pluginCallbacks.length; i++) {\n      const plugin = this.pluginCallbacks[i](parser)\n\n      if (!plugin.name) console.error('THREE.GLTFLoader: Invalid plugin found: missing name')\n\n      plugins[plugin.name] = plugin\n\n      // Workaround to avoid determining as unknown extension\n      // in addUnknownExtensionsToUserData().\n      // Remove this workaround if we move all the existing\n      // extension handlers to plugin system\n      extensions[plugin.name] = true\n    }\n\n    if (json.extensionsUsed) {\n      for (let i = 0; i < json.extensionsUsed.length; ++i) {\n        const extensionName = json.extensionsUsed[i]\n        const extensionsRequired = json.extensionsRequired || []\n\n        switch (extensionName) {\n          case EXTENSIONS.KHR_MATERIALS_UNLIT:\n            extensions[extensionName] = new GLTFMaterialsUnlitExtension()\n            break\n\n          case EXTENSIONS.KHR_DRACO_MESH_COMPRESSION:\n            extensions[extensionName] = new GLTFDracoMeshCompressionExtension(json, this.dracoLoader)\n            break\n\n          case EXTENSIONS.KHR_TEXTURE_TRANSFORM:\n            extensions[extensionName] = new GLTFTextureTransformExtension()\n            break\n\n          case EXTENSIONS.KHR_MESH_QUANTIZATION:\n            extensions[extensionName] = new GLTFMeshQuantizationExtension()\n            break\n\n          default:\n            if (extensionsRequired.indexOf(extensionName) >= 0 && plugins[extensionName] === undefined) {\n              console.warn('THREE.GLTFLoader: Unknown extension \"' + extensionName + '\".')\n            }\n        }\n      }\n    }\n\n    parser.setExtensions(extensions)\n    parser.setPlugins(plugins)\n    parser.parse(onLoad, onError)\n  }\n\n  parseAsync(data, path) {\n    const scope = this\n\n    return new Promise(function (resolve, reject) {\n      scope.parse(data, path, resolve, reject)\n    })\n  }\n}\n\n/* GLTFREGISTRY */\n\nfunction GLTFRegistry() {\n  let objects = {}\n\n  return {\n    get: function (key) {\n      return objects[key]\n    },\n\n    add: function (key, object) {\n      objects[key] = object\n    },\n\n    remove: function (key) {\n      delete objects[key]\n    },\n\n    removeAll: function () {\n      objects = {}\n    },\n  }\n}\n\n/*********************************/\n/********** EXTENSIONS ***********/\n/*********************************/\n\nconst EXTENSIONS = {\n  KHR_BINARY_GLTF: 'KHR_binary_glTF',\n  KHR_DRACO_MESH_COMPRESSION: 'KHR_draco_mesh_compression',\n  KHR_LIGHTS_PUNCTUAL: 'KHR_lights_punctual',\n  KHR_MATERIALS_CLEARCOAT: 'KHR_materials_clearcoat',\n  KHR_MATERIALS_DISPERSION: 'KHR_materials_dispersion',\n  KHR_MATERIALS_IOR: 'KHR_materials_ior',\n  KHR_MATERIALS_SHEEN: 'KHR_materials_sheen',\n  KHR_MATERIALS_SPECULAR: 'KHR_materials_specular',\n  KHR_MATERIALS_TRANSMISSION: 'KHR_materials_transmission',\n  KHR_MATERIALS_IRIDESCENCE: 'KHR_materials_iridescence',\n  KHR_MATERIALS_ANISOTROPY: 'KHR_materials_anisotropy',\n  KHR_MATERIALS_UNLIT: 'KHR_materials_unlit',\n  KHR_MATERIALS_VOLUME: 'KHR_materials_volume',\n  KHR_TEXTURE_BASISU: 'KHR_texture_basisu',\n  KHR_TEXTURE_TRANSFORM: 'KHR_texture_transform',\n  KHR_MESH_QUANTIZATION: 'KHR_mesh_quantization',\n  KHR_MATERIALS_EMISSIVE_STRENGTH: 'KHR_materials_emissive_strength',\n  EXT_MATERIALS_BUMP: 'EXT_materials_bump',\n  EXT_TEXTURE_WEBP: 'EXT_texture_webp',\n  EXT_TEXTURE_AVIF: 'EXT_texture_avif',\n  EXT_MESHOPT_COMPRESSION: 'EXT_meshopt_compression',\n  EXT_MESH_GPU_INSTANCING: 'EXT_mesh_gpu_instancing',\n}\n\n/**\n * Punctual Lights Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_lights_punctual\n */\nclass GLTFLightsExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_LIGHTS_PUNCTUAL\n\n    // Object3D instance caches\n    this.cache = { refs: {}, uses: {} }\n  }\n\n  _markDefs() {\n    const parser = this.parser\n    const nodeDefs = this.parser.json.nodes || []\n\n    for (let nodeIndex = 0, nodeLength = nodeDefs.length; nodeIndex < nodeLength; nodeIndex++) {\n      const nodeDef = nodeDefs[nodeIndex]\n\n      if (nodeDef.extensions && nodeDef.extensions[this.name] && nodeDef.extensions[this.name].light !== undefined) {\n        parser._addNodeRef(this.cache, nodeDef.extensions[this.name].light)\n      }\n    }\n  }\n\n  _loadLight(lightIndex) {\n    const parser = this.parser\n    const cacheKey = 'light:' + lightIndex\n    let dependency = parser.cache.get(cacheKey)\n\n    if (dependency) return dependency\n\n    const json = parser.json\n    const extensions = (json.extensions && json.extensions[this.name]) || {}\n    const lightDefs = extensions.lights || []\n    const lightDef = lightDefs[lightIndex]\n    let lightNode\n\n    const color = new Color(0xffffff)\n\n    if (lightDef.color !== undefined)\n      color.setRGB(lightDef.color[0], lightDef.color[1], lightDef.color[2], LinearSRGBColorSpace)\n\n    const range = lightDef.range !== undefined ? lightDef.range : 0\n\n    switch (lightDef.type) {\n      case 'directional':\n        lightNode = new DirectionalLight(color)\n        lightNode.target.position.set(0, 0, -1)\n        lightNode.add(lightNode.target)\n        break\n\n      case 'point':\n        lightNode = new PointLight(color)\n        lightNode.distance = range\n        break\n\n      case 'spot':\n        lightNode = new SpotLight(color)\n        lightNode.distance = range\n        // Handle spotlight properties.\n        lightDef.spot = lightDef.spot || {}\n        lightDef.spot.innerConeAngle = lightDef.spot.innerConeAngle !== undefined ? lightDef.spot.innerConeAngle : 0\n        lightDef.spot.outerConeAngle =\n          lightDef.spot.outerConeAngle !== undefined ? lightDef.spot.outerConeAngle : Math.PI / 4.0\n        lightNode.angle = lightDef.spot.outerConeAngle\n        lightNode.penumbra = 1.0 - lightDef.spot.innerConeAngle / lightDef.spot.outerConeAngle\n        lightNode.target.position.set(0, 0, -1)\n        lightNode.add(lightNode.target)\n        break\n\n      default:\n        throw new Error('THREE.GLTFLoader: Unexpected light type: ' + lightDef.type)\n    }\n\n    // Some lights (e.g. spot) default to a position other than the origin. Reset the position\n    // here, because node-level parsing will only override position if explicitly specified.\n    lightNode.position.set(0, 0, 0)\n\n    lightNode.decay = 2\n\n    assignExtrasToUserData(lightNode, lightDef)\n\n    if (lightDef.intensity !== undefined) lightNode.intensity = lightDef.intensity\n\n    lightNode.name = parser.createUniqueName(lightDef.name || 'light_' + lightIndex)\n\n    dependency = Promise.resolve(lightNode)\n\n    parser.cache.add(cacheKey, dependency)\n\n    return dependency\n  }\n\n  getDependency(type, index) {\n    if (type !== 'light') return\n\n    return this._loadLight(index)\n  }\n\n  createNodeAttachment(nodeIndex) {\n    const self = this\n    const parser = this.parser\n    const json = parser.json\n    const nodeDef = json.nodes[nodeIndex]\n    const lightDef = (nodeDef.extensions && nodeDef.extensions[this.name]) || {}\n    const lightIndex = lightDef.light\n\n    if (lightIndex === undefined) return null\n\n    return this._loadLight(lightIndex).then(function (light) {\n      return parser._getNodeRef(self.cache, lightIndex, light)\n    })\n  }\n}\n\n/**\n * Unlit Materials Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_unlit\n */\nclass GLTFMaterialsUnlitExtension {\n  constructor() {\n    this.name = EXTENSIONS.KHR_MATERIALS_UNLIT\n  }\n\n  getMaterialType() {\n    return MeshBasicMaterial\n  }\n\n  extendParams(materialParams, materialDef, parser) {\n    const pending = []\n\n    materialParams.color = new Color(1.0, 1.0, 1.0)\n    materialParams.opacity = 1.0\n\n    const metallicRoughness = materialDef.pbrMetallicRoughness\n\n    if (metallicRoughness) {\n      if (Array.isArray(metallicRoughness.baseColorFactor)) {\n        const array = metallicRoughness.baseColorFactor\n\n        materialParams.color.setRGB(array[0], array[1], array[2], LinearSRGBColorSpace)\n        materialParams.opacity = array[3]\n      }\n\n      if (metallicRoughness.baseColorTexture !== undefined) {\n        pending.push(parser.assignTexture(materialParams, 'map', metallicRoughness.baseColorTexture, SRGBColorSpace))\n      }\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials Emissive Strength Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/blob/5768b3ce0ef32bc39cdf1bef10b948586635ead3/extensions/2.0/Khronos/KHR_materials_emissive_strength/README.md\n */\nclass GLTFMaterialsEmissiveStrengthExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_EMISSIVE_STRENGTH\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const emissiveStrength = materialDef.extensions[this.name].emissiveStrength\n\n    if (emissiveStrength !== undefined) {\n      materialParams.emissiveIntensity = emissiveStrength\n    }\n\n    return Promise.resolve()\n  }\n}\n\n/**\n * Clearcoat Materials Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_clearcoat\n */\nclass GLTFMaterialsClearcoatExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_CLEARCOAT\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    if (extension.clearcoatFactor !== undefined) {\n      materialParams.clearcoat = extension.clearcoatFactor\n    }\n\n    if (extension.clearcoatTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'clearcoatMap', extension.clearcoatTexture))\n    }\n\n    if (extension.clearcoatRoughnessFactor !== undefined) {\n      materialParams.clearcoatRoughness = extension.clearcoatRoughnessFactor\n    }\n\n    if (extension.clearcoatRoughnessTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'clearcoatRoughnessMap', extension.clearcoatRoughnessTexture))\n    }\n\n    if (extension.clearcoatNormalTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'clearcoatNormalMap', extension.clearcoatNormalTexture))\n\n      if (extension.clearcoatNormalTexture.scale !== undefined) {\n        const scale = extension.clearcoatNormalTexture.scale\n\n        materialParams.clearcoatNormalScale = new Vector2(scale, scale)\n      }\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials dispersion Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Khronos/KHR_materials_dispersion\n */\nclass GLTFMaterialsDispersionExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_DISPERSION\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const extension = materialDef.extensions[this.name]\n\n    materialParams.dispersion = extension.dispersion !== undefined ? extension.dispersion : 0\n\n    return Promise.resolve()\n  }\n}\n\n/**\n * Iridescence Materials Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_iridescence\n */\nclass GLTFMaterialsIridescenceExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_IRIDESCENCE\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    if (extension.iridescenceFactor !== undefined) {\n      materialParams.iridescence = extension.iridescenceFactor\n    }\n\n    if (extension.iridescenceTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'iridescenceMap', extension.iridescenceTexture))\n    }\n\n    if (extension.iridescenceIor !== undefined) {\n      materialParams.iridescenceIOR = extension.iridescenceIor\n    }\n\n    if (materialParams.iridescenceThicknessRange === undefined) {\n      materialParams.iridescenceThicknessRange = [100, 400]\n    }\n\n    if (extension.iridescenceThicknessMinimum !== undefined) {\n      materialParams.iridescenceThicknessRange[0] = extension.iridescenceThicknessMinimum\n    }\n\n    if (extension.iridescenceThicknessMaximum !== undefined) {\n      materialParams.iridescenceThicknessRange[1] = extension.iridescenceThicknessMaximum\n    }\n\n    if (extension.iridescenceThicknessTexture !== undefined) {\n      pending.push(\n        parser.assignTexture(materialParams, 'iridescenceThicknessMap', extension.iridescenceThicknessTexture),\n      )\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Sheen Materials Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/main/extensions/2.0/Khronos/KHR_materials_sheen\n */\nclass GLTFMaterialsSheenExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_SHEEN\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    materialParams.sheenColor = new Color(0, 0, 0)\n    materialParams.sheenRoughness = 0\n    materialParams.sheen = 1\n\n    const extension = materialDef.extensions[this.name]\n\n    if (extension.sheenColorFactor !== undefined) {\n      const colorFactor = extension.sheenColorFactor\n      materialParams.sheenColor.setRGB(colorFactor[0], colorFactor[1], colorFactor[2], LinearSRGBColorSpace)\n    }\n\n    if (extension.sheenRoughnessFactor !== undefined) {\n      materialParams.sheenRoughness = extension.sheenRoughnessFactor\n    }\n\n    if (extension.sheenColorTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'sheenColorMap', extension.sheenColorTexture, SRGBColorSpace))\n    }\n\n    if (extension.sheenRoughnessTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'sheenRoughnessMap', extension.sheenRoughnessTexture))\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Transmission Materials Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_transmission\n * Draft: https://github.com/KhronosGroup/glTF/pull/1698\n */\nclass GLTFMaterialsTransmissionExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_TRANSMISSION\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    if (extension.transmissionFactor !== undefined) {\n      materialParams.transmission = extension.transmissionFactor\n    }\n\n    if (extension.transmissionTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'transmissionMap', extension.transmissionTexture))\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials Volume Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_volume\n */\nclass GLTFMaterialsVolumeExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_VOLUME\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    materialParams.thickness = extension.thicknessFactor !== undefined ? extension.thicknessFactor : 0\n\n    if (extension.thicknessTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'thicknessMap', extension.thicknessTexture))\n    }\n\n    materialParams.attenuationDistance = extension.attenuationDistance || Infinity\n\n    const colorArray = extension.attenuationColor || [1, 1, 1]\n    materialParams.attenuationColor = new Color().setRGB(\n      colorArray[0],\n      colorArray[1],\n      colorArray[2],\n      LinearSRGBColorSpace,\n    )\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials ior Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_ior\n */\nclass GLTFMaterialsIorExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_IOR\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const extension = materialDef.extensions[this.name]\n\n    materialParams.ior = extension.ior !== undefined ? extension.ior : 1.5\n\n    return Promise.resolve()\n  }\n}\n\n/**\n * Materials specular Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_specular\n */\nclass GLTFMaterialsSpecularExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_SPECULAR\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    materialParams.specularIntensity = extension.specularFactor !== undefined ? extension.specularFactor : 1.0\n\n    if (extension.specularTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'specularIntensityMap', extension.specularTexture))\n    }\n\n    const colorArray = extension.specularColorFactor || [1, 1, 1]\n    materialParams.specularColor = new Color().setRGB(colorArray[0], colorArray[1], colorArray[2], LinearSRGBColorSpace)\n\n    if (extension.specularColorTexture !== undefined) {\n      pending.push(\n        parser.assignTexture(materialParams, 'specularColorMap', extension.specularColorTexture, SRGBColorSpace),\n      )\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials bump Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/EXT_materials_bump\n */\nclass GLTFMaterialsBumpExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.EXT_MATERIALS_BUMP\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    materialParams.bumpScale = extension.bumpFactor !== undefined ? extension.bumpFactor : 1.0\n\n    if (extension.bumpTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'bumpMap', extension.bumpTexture))\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * Materials anisotropy Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_anisotropy\n */\nclass GLTFMaterialsAnisotropyExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_MATERIALS_ANISOTROPY\n  }\n\n  getMaterialType(materialIndex) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null\n\n    return MeshPhysicalMaterial\n  }\n\n  extendMaterialParams(materialIndex, materialParams) {\n    const parser = this.parser\n    const materialDef = parser.json.materials[materialIndex]\n\n    if (!materialDef.extensions || !materialDef.extensions[this.name]) {\n      return Promise.resolve()\n    }\n\n    const pending = []\n\n    const extension = materialDef.extensions[this.name]\n\n    if (extension.anisotropyStrength !== undefined) {\n      materialParams.anisotropy = extension.anisotropyStrength\n    }\n\n    if (extension.anisotropyRotation !== undefined) {\n      materialParams.anisotropyRotation = extension.anisotropyRotation\n    }\n\n    if (extension.anisotropyTexture !== undefined) {\n      pending.push(parser.assignTexture(materialParams, 'anisotropyMap', extension.anisotropyTexture))\n    }\n\n    return Promise.all(pending)\n  }\n}\n\n/**\n * BasisU Texture Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_texture_basisu\n */\nclass GLTFTextureBasisUExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.KHR_TEXTURE_BASISU\n  }\n\n  loadTexture(textureIndex) {\n    const parser = this.parser\n    const json = parser.json\n\n    const textureDef = json.textures[textureIndex]\n\n    if (!textureDef.extensions || !textureDef.extensions[this.name]) {\n      return null\n    }\n\n    const extension = textureDef.extensions[this.name]\n    const loader = parser.options.ktx2Loader\n\n    if (!loader) {\n      if (json.extensionsRequired && json.extensionsRequired.indexOf(this.name) >= 0) {\n        throw new Error('THREE.GLTFLoader: setKTX2Loader must be called before loading KTX2 textures')\n      } else {\n        // Assumes that the extension is optional and that a fallback texture is present\n        return null\n      }\n    }\n\n    return parser.loadTextureImage(textureIndex, extension.source, loader)\n  }\n}\n\n/**\n * WebP Texture Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_texture_webp\n */\nclass GLTFTextureWebPExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.EXT_TEXTURE_WEBP\n    this.isSupported = null\n  }\n\n  loadTexture(textureIndex) {\n    const name = this.name\n    const parser = this.parser\n    const json = parser.json\n\n    const textureDef = json.textures[textureIndex]\n\n    if (!textureDef.extensions || !textureDef.extensions[name]) {\n      return null\n    }\n\n    const extension = textureDef.extensions[name]\n    const source = json.images[extension.source]\n\n    let loader = parser.textureLoader\n    if (source.uri) {\n      const handler = parser.options.manager.getHandler(source.uri)\n      if (handler !== null) loader = handler\n    }\n\n    return this.detectSupport().then(function (isSupported) {\n      if (isSupported) return parser.loadTextureImage(textureIndex, extension.source, loader)\n\n      if (json.extensionsRequired && json.extensionsRequired.indexOf(name) >= 0) {\n        throw new Error('THREE.GLTFLoader: WebP required by asset but unsupported.')\n      }\n\n      // Fall back to PNG or JPEG.\n      return parser.loadTexture(textureIndex)\n    })\n  }\n\n  detectSupport() {\n    if (!this.isSupported) {\n      this.isSupported = new Promise(function (resolve) {\n        const image = new Image()\n\n        // Lossy test image. Support for lossy images doesn't guarantee support for all\n        // WebP images, unfortunately.\n        image.src = 'data:image/webp;base64,UklGRiIAAABXRUJQVlA4IBYAAAAwAQCdASoBAAEADsD+JaQAA3AAAAAA'\n\n        image.onload = image.onerror = function () {\n          resolve(image.height === 1)\n        }\n      })\n    }\n\n    return this.isSupported\n  }\n}\n\n/**\n * AVIF Texture Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_texture_avif\n */\nclass GLTFTextureAVIFExtension {\n  constructor(parser) {\n    this.parser = parser\n    this.name = EXTENSIONS.EXT_TEXTURE_AVIF\n    this.isSupported = null\n  }\n\n  loadTexture(textureIndex) {\n    const name = this.name\n    const parser = this.parser\n    const json = parser.json\n\n    const textureDef = json.textures[textureIndex]\n\n    if (!textureDef.extensions || !textureDef.extensions[name]) {\n      return null\n    }\n\n    const extension = textureDef.extensions[name]\n    const source = json.images[extension.source]\n\n    let loader = parser.textureLoader\n    if (source.uri) {\n      const handler = parser.options.manager.getHandler(source.uri)\n      if (handler !== null) loader = handler\n    }\n\n    return this.detectSupport().then(function (isSupported) {\n      if (isSupported) return parser.loadTextureImage(textureIndex, extension.source, loader)\n\n      if (json.extensionsRequired && json.extensionsRequired.indexOf(name) >= 0) {\n        throw new Error('THREE.GLTFLoader: AVIF required by asset but unsupported.')\n      }\n\n      // Fall back to PNG or JPEG.\n      return parser.loadTexture(textureIndex)\n    })\n  }\n\n  detectSupport() {\n    if (!this.isSupported) {\n      this.isSupported = new Promise(function (resolve) {\n        const image = new Image()\n\n        // Lossy test image.\n        image.src =\n          'data:image/avif;base64,AAAAIGZ0eXBhdmlmAAAAAGF2aWZtaWYxbWlhZk1BMUIAAADybWV0YQAAAAAAAAAoaGRscgAAAAAAAAAAcGljdAAAAAAAAAAAAAAAAGxpYmF2aWYAAAAADnBpdG0AAAAAAAEAAAAeaWxvYwAAAABEAAABAAEAAAABAAABGgAAABcAAAAoaWluZgAAAAAAAQAAABppbmZlAgAAAAABAABhdjAxQ29sb3IAAAAAamlwcnAAAABLaXBjbwAAABRpc3BlAAAAAAAAAAEAAAABAAAAEHBpeGkAAAAAAwgICAAAAAxhdjFDgQAMAAAAABNjb2xybmNseAACAAIABoAAAAAXaXBtYQAAAAAAAAABAAEEAQKDBAAAAB9tZGF0EgAKCBgABogQEDQgMgkQAAAAB8dSLfI='\n        image.onload = image.onerror = function () {\n          resolve(image.height === 1)\n        }\n      })\n    }\n\n    return this.isSupported\n  }\n}\n\n/**\n * meshopt BufferView Compression Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_meshopt_compression\n */\nclass GLTFMeshoptCompression {\n  constructor(parser) {\n    this.name = EXTENSIONS.EXT_MESHOPT_COMPRESSION\n    this.parser = parser\n  }\n\n  loadBufferView(index) {\n    const json = this.parser.json\n    const bufferView = json.bufferViews[index]\n\n    if (bufferView.extensions && bufferView.extensions[this.name]) {\n      const extensionDef = bufferView.extensions[this.name]\n\n      const buffer = this.parser.getDependency('buffer', extensionDef.buffer)\n      const decoder = this.parser.options.meshoptDecoder\n\n      if (!decoder || !decoder.supported) {\n        if (json.extensionsRequired && json.extensionsRequired.indexOf(this.name) >= 0) {\n          throw new Error('THREE.GLTFLoader: setMeshoptDecoder must be called before loading compressed files')\n        } else {\n          // Assumes that the extension is optional and that fallback buffer data is present\n          return null\n        }\n      }\n\n      return buffer.then(function (res) {\n        const byteOffset = extensionDef.byteOffset || 0\n        const byteLength = extensionDef.byteLength || 0\n\n        const count = extensionDef.count\n        const stride = extensionDef.byteStride\n\n        const source = new Uint8Array(res, byteOffset, byteLength)\n\n        if (decoder.decodeGltfBufferAsync) {\n          return decoder\n            .decodeGltfBufferAsync(count, stride, source, extensionDef.mode, extensionDef.filter)\n            .then(function (res) {\n              return res.buffer\n            })\n        } else {\n          // Support for MeshoptDecoder 0.18 or earlier, without decodeGltfBufferAsync\n          return decoder.ready.then(function () {\n            const result = new ArrayBuffer(count * stride)\n            decoder.decodeGltfBuffer(\n              new Uint8Array(result),\n              count,\n              stride,\n              source,\n              extensionDef.mode,\n              extensionDef.filter,\n            )\n            return result\n          })\n        }\n      })\n    } else {\n      return null\n    }\n  }\n}\n\n/**\n * GPU Instancing Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_mesh_gpu_instancing\n *\n */\nclass GLTFMeshGpuInstancing {\n  constructor(parser) {\n    this.name = EXTENSIONS.EXT_MESH_GPU_INSTANCING\n    this.parser = parser\n  }\n\n  createNodeMesh(nodeIndex) {\n    const json = this.parser.json\n    const nodeDef = json.nodes[nodeIndex]\n\n    if (!nodeDef.extensions || !nodeDef.extensions[this.name] || nodeDef.mesh === undefined) {\n      return null\n    }\n\n    const meshDef = json.meshes[nodeDef.mesh]\n\n    // No Points or Lines + Instancing support yet\n\n    for (const primitive of meshDef.primitives) {\n      if (\n        primitive.mode !== WEBGL_CONSTANTS.TRIANGLES &&\n        primitive.mode !== WEBGL_CONSTANTS.TRIANGLE_STRIP &&\n        primitive.mode !== WEBGL_CONSTANTS.TRIANGLE_FAN &&\n        primitive.mode !== undefined\n      ) {\n        return null\n      }\n    }\n\n    const extensionDef = nodeDef.extensions[this.name]\n    const attributesDef = extensionDef.attributes\n\n    // @TODO: Can we support InstancedMesh + SkinnedMesh?\n\n    const pending = []\n    const attributes = {}\n\n    for (const key in attributesDef) {\n      pending.push(\n        this.parser.getDependency('accessor', attributesDef[key]).then((accessor) => {\n          attributes[key] = accessor\n          return attributes[key]\n        }),\n      )\n    }\n\n    if (pending.length < 1) {\n      return null\n    }\n\n    pending.push(this.parser.createNodeMesh(nodeIndex))\n\n    return Promise.all(pending).then((results) => {\n      const nodeObject = results.pop()\n      const meshes = nodeObject.isGroup ? nodeObject.children : [nodeObject]\n      const count = results[0].count // All attribute counts should be same\n      const instancedMeshes = []\n\n      for (const mesh of meshes) {\n        // Temporal variables\n        const m = new Matrix4()\n        const p = new Vector3()\n        const q = new Quaternion()\n        const s = new Vector3(1, 1, 1)\n\n        const instancedMesh = new InstancedMesh(mesh.geometry, mesh.material, count)\n\n        for (let i = 0; i < count; i++) {\n          if (attributes.TRANSLATION) {\n            p.fromBufferAttribute(attributes.TRANSLATION, i)\n          }\n\n          if (attributes.ROTATION) {\n            q.fromBufferAttribute(attributes.ROTATION, i)\n          }\n\n          if (attributes.SCALE) {\n            s.fromBufferAttribute(attributes.SCALE, i)\n          }\n\n          instancedMesh.setMatrixAt(i, m.compose(p, q, s))\n        }\n\n        // Add instance attributes to the geometry, excluding TRS.\n        for (const attributeName in attributes) {\n          if (attributeName === '_COLOR_0') {\n            const attr = attributes[attributeName]\n            instancedMesh.instanceColor = new InstancedBufferAttribute(attr.array, attr.itemSize, attr.normalized)\n          } else if (attributeName !== 'TRANSLATION' && attributeName !== 'ROTATION' && attributeName !== 'SCALE') {\n            mesh.geometry.setAttribute(attributeName, attributes[attributeName])\n          }\n        }\n\n        // Just in case\n        Object3D.prototype.copy.call(instancedMesh, mesh)\n\n        this.parser.assignFinalMaterial(instancedMesh)\n\n        instancedMeshes.push(instancedMesh)\n      }\n\n      if (nodeObject.isGroup) {\n        nodeObject.clear()\n\n        nodeObject.add(...instancedMeshes)\n\n        return nodeObject\n      }\n\n      return instancedMeshes[0]\n    })\n  }\n}\n\n/* BINARY EXTENSION */\nconst BINARY_EXTENSION_HEADER_MAGIC = 'glTF'\nconst BINARY_EXTENSION_HEADER_LENGTH = 12\nconst BINARY_EXTENSION_CHUNK_TYPES = { JSON: 0x4e4f534a, BIN: 0x004e4942 }\n\nclass GLTFBinaryExtension {\n  constructor(data) {\n    this.name = EXTENSIONS.KHR_BINARY_GLTF\n    this.content = null\n    this.body = null\n\n    const headerView = new DataView(data, 0, BINARY_EXTENSION_HEADER_LENGTH)\n\n    this.header = {\n      magic: decodeText(new Uint8Array(data.slice(0, 4))),\n      version: headerView.getUint32(4, true),\n      length: headerView.getUint32(8, true),\n    }\n\n    if (this.header.magic !== BINARY_EXTENSION_HEADER_MAGIC) {\n      throw new Error('THREE.GLTFLoader: Unsupported glTF-Binary header.')\n    } else if (this.header.version < 2.0) {\n      throw new Error('THREE.GLTFLoader: Legacy binary file detected.')\n    }\n\n    const chunkContentsLength = this.header.length - BINARY_EXTENSION_HEADER_LENGTH\n    const chunkView = new DataView(data, BINARY_EXTENSION_HEADER_LENGTH)\n    let chunkIndex = 0\n\n    while (chunkIndex < chunkContentsLength) {\n      const chunkLength = chunkView.getUint32(chunkIndex, true)\n      chunkIndex += 4\n\n      const chunkType = chunkView.getUint32(chunkIndex, true)\n      chunkIndex += 4\n\n      if (chunkType === BINARY_EXTENSION_CHUNK_TYPES.JSON) {\n        const contentArray = new Uint8Array(data, BINARY_EXTENSION_HEADER_LENGTH + chunkIndex, chunkLength)\n        this.content = decodeText(contentArray)\n      } else if (chunkType === BINARY_EXTENSION_CHUNK_TYPES.BIN) {\n        const byteOffset = BINARY_EXTENSION_HEADER_LENGTH + chunkIndex\n        this.body = data.slice(byteOffset, byteOffset + chunkLength)\n      }\n\n      // Clients must ignore chunks with unknown types.\n\n      chunkIndex += chunkLength\n    }\n\n    if (this.content === null) {\n      throw new Error('THREE.GLTFLoader: JSON content not found.')\n    }\n  }\n}\n\n/**\n * DRACO Mesh Compression Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_draco_mesh_compression\n */\nclass GLTFDracoMeshCompressionExtension {\n  constructor(json, dracoLoader) {\n    if (!dracoLoader) {\n      throw new Error('THREE.GLTFLoader: No DRACOLoader instance provided.')\n    }\n\n    this.name = EXTENSIONS.KHR_DRACO_MESH_COMPRESSION\n    this.json = json\n    this.dracoLoader = dracoLoader\n    this.dracoLoader.preload()\n  }\n\n  decodePrimitive(primitive, parser) {\n    const json = this.json\n    const dracoLoader = this.dracoLoader\n    const bufferViewIndex = primitive.extensions[this.name].bufferView\n    const gltfAttributeMap = primitive.extensions[this.name].attributes\n    const threeAttributeMap = {}\n    const attributeNormalizedMap = {}\n    const attributeTypeMap = {}\n\n    for (const attributeName in gltfAttributeMap) {\n      const threeAttributeName = ATTRIBUTES[attributeName] || attributeName.toLowerCase()\n\n      threeAttributeMap[threeAttributeName] = gltfAttributeMap[attributeName]\n    }\n\n    for (const attributeName in primitive.attributes) {\n      const threeAttributeName = ATTRIBUTES[attributeName] || attributeName.toLowerCase()\n\n      if (gltfAttributeMap[attributeName] !== undefined) {\n        const accessorDef = json.accessors[primitive.attributes[attributeName]]\n        const componentType = WEBGL_COMPONENT_TYPES[accessorDef.componentType]\n\n        attributeTypeMap[threeAttributeName] = componentType.name\n        attributeNormalizedMap[threeAttributeName] = accessorDef.normalized === true\n      }\n    }\n\n    return parser.getDependency('bufferView', bufferViewIndex).then(function (bufferView) {\n      return new Promise(function (resolve, reject) {\n        dracoLoader.decodeDracoFile(\n          bufferView,\n          function (geometry) {\n            for (const attributeName in geometry.attributes) {\n              const attribute = geometry.attributes[attributeName]\n              const normalized = attributeNormalizedMap[attributeName]\n\n              if (normalized !== undefined) attribute.normalized = normalized\n            }\n\n            resolve(geometry)\n          },\n          threeAttributeMap,\n          attributeTypeMap,\n          LinearSRGBColorSpace,\n          reject,\n        )\n      })\n    })\n  }\n}\n\n/**\n * Texture Transform Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_texture_transform\n */\nclass GLTFTextureTransformExtension {\n  constructor() {\n    this.name = EXTENSIONS.KHR_TEXTURE_TRANSFORM\n  }\n\n  extendTexture(texture, transform) {\n    if (\n      (transform.texCoord === undefined || transform.texCoord === texture.channel) &&\n      transform.offset === undefined &&\n      transform.rotation === undefined &&\n      transform.scale === undefined\n    ) {\n      // See https://github.com/mrdoob/three.js/issues/21819.\n      return texture\n    }\n\n    texture = texture.clone()\n\n    if (transform.texCoord !== undefined) {\n      texture.channel = transform.texCoord\n    }\n\n    if (transform.offset !== undefined) {\n      texture.offset.fromArray(transform.offset)\n    }\n\n    if (transform.rotation !== undefined) {\n      texture.rotation = transform.rotation\n    }\n\n    if (transform.scale !== undefined) {\n      texture.repeat.fromArray(transform.scale)\n    }\n\n    texture.needsUpdate = true\n\n    return texture\n  }\n}\n\n/**\n * Mesh Quantization Extension\n *\n * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_mesh_quantization\n */\nclass GLTFMeshQuantizationExtension {\n  constructor() {\n    this.name = EXTENSIONS.KHR_MESH_QUANTIZATION\n  }\n}\n\n/*********************************/\n/********** INTERPOLATION ********/\n/*********************************/\n\n// Spline Interpolation\n// Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#appendix-c-spline-interpolation\nclass GLTFCubicSplineInterpolant extends Interpolant {\n  constructor(parameterPositions, sampleValues, sampleSize, resultBuffer) {\n    super(parameterPositions, sampleValues, sampleSize, resultBuffer)\n  }\n\n  copySampleValue_(index) {\n    // Copies a sample value to the result buffer. See description of glTF\n    // CUBICSPLINE values layout in interpolate_() function below.\n\n    const result = this.resultBuffer,\n      values = this.sampleValues,\n      valueSize = this.valueSize,\n      offset = index * valueSize * 3 + valueSize\n\n    for (let i = 0; i !== valueSize; i++) {\n      result[i] = values[offset + i]\n    }\n\n    return result\n  }\n\n  interpolate_(i1, t0, t, t1) {\n    const result = this.resultBuffer\n    const values = this.sampleValues\n    const stride = this.valueSize\n\n    const stride2 = stride * 2\n    const stride3 = stride * 3\n\n    const td = t1 - t0\n\n    const p = (t - t0) / td\n    const pp = p * p\n    const ppp = pp * p\n\n    const offset1 = i1 * stride3\n    const o