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bytev-charts

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基于echarts和JavaScript及ES6封装的一个可以直接调用的图表组件库,内置主题设计,简单快捷,且支持用户自定义配置; npm 安装方式: npm install bytev-charts 若启动提示还需额外install插件,则运行 npm install @babel/runtime-corejs2 即可;

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import "core-js/modules/es.array.every.js";
import "core-js/modules/es.object.to-string.js";
import "core-js/modules/es.array.iterator.js";
import "core-js/modules/es.array-buffer.slice.js";
import "core-js/modules/es.typed-array.uint8-array.js";
import "core-js/modules/es.typed-array.copy-within.js";
import "core-js/modules/es.typed-array.every.js";
import "core-js/modules/es.typed-array.fill.js";
import "core-js/modules/es.typed-array.filter.js";
import "core-js/modules/es.typed-array.find.js";
import "core-js/modules/es.typed-array.find-index.js";
import "core-js/modules/es.typed-array.for-each.js";
import "core-js/modules/es.typed-array.includes.js";
import "core-js/modules/es.typed-array.index-of.js";
import "core-js/modules/es.typed-array.iterator.js";
import "core-js/modules/es.typed-array.join.js";
import "core-js/modules/es.typed-array.last-index-of.js";
import "core-js/modules/es.typed-array.map.js";
import "core-js/modules/es.typed-array.reduce.js";
import "core-js/modules/es.typed-array.reduce-right.js";
import "core-js/modules/es.typed-array.reverse.js";
import "core-js/modules/es.typed-array.set.js";
import "core-js/modules/es.typed-array.slice.js";
import "core-js/modules/es.typed-array.some.js";
import "core-js/modules/es.typed-array.sort.js";
import "core-js/modules/es.typed-array.subarray.js";
import "core-js/modules/es.typed-array.to-locale-string.js";
import "core-js/modules/es.typed-array.to-string.js";
import "core-js/modules/es.array-buffer.constructor.js";
import "core-js/modules/es.array.fill.js";
import "core-js/modules/es.number.constructor.js";
import "core-js/modules/es.promise.js";
import "core-js/modules/es.function.name.js";
import "core-js/modules/es.string.repeat.js";
import "core-js/modules/es.data-view.js";
import "core-js/modules/es.typed-array.float32-array.js";
import "core-js/modules/es.typed-array.uint32-array.js";
import "core-js/modules/es.typed-array.uint16-array.js";
import "core-js/modules/es.date.to-string.js";
import "core-js/modules/es.regexp.to-string.js";
import "core-js/modules/es.array.concat.js";
import "core-js/modules/es.array.map.js";
import "core-js/modules/es.array.join.js";
import "core-js/modules/es.regexp.exec.js";
import "core-js/modules/web.dom-collections.iterator.js";
import "core-js/modules/es.string.iterator.js";
import "core-js/modules/es.array.slice.js";
import _Object$assign from "@babel/runtime-corejs2/core-js/object/assign";
import _Map from "@babel/runtime-corejs2/core-js/map";
import _Object$keys from "@babel/runtime-corejs2/core-js/object/keys";
import _JSON$stringify from "@babel/runtime-corejs2/core-js/json/stringify";
import _Promise from "@babel/runtime-corejs2/core-js/promise";
import _Array$isArray from "@babel/runtime-corejs2/core-js/array/is-array";
console.warn("THREE.GLTFExporter: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/#manual/en/introduction/Installation."); //------------------------------------------------------------------------------
// Constants
//------------------------------------------------------------------------------

var WEBGL_CONSTANTS = {
  POINTS: 0x0000,
  LINES: 0x0001,
  LINE_LOOP: 0x0002,
  LINE_STRIP: 0x0003,
  TRIANGLES: 0x0004,
  TRIANGLE_STRIP: 0x0005,
  TRIANGLE_FAN: 0x0006,
  UNSIGNED_BYTE: 0x1401,
  UNSIGNED_SHORT: 0x1403,
  FLOAT: 0x1406,
  UNSIGNED_INT: 0x1405,
  ARRAY_BUFFER: 0x8892,
  ELEMENT_ARRAY_BUFFER: 0x8893,
  NEAREST: 0x2600,
  LINEAR: 0x2601,
  NEAREST_MIPMAP_NEAREST: 0x2700,
  LINEAR_MIPMAP_NEAREST: 0x2701,
  NEAREST_MIPMAP_LINEAR: 0x2702,
  LINEAR_MIPMAP_LINEAR: 0x2703,
  CLAMP_TO_EDGE: 33071,
  MIRRORED_REPEAT: 33648,
  REPEAT: 10497
};
var THREE_TO_WEBGL = {};
THREE_TO_WEBGL[THREE.NearestFilter] = WEBGL_CONSTANTS.NEAREST;
THREE_TO_WEBGL[THREE.NearestMipmapNearestFilter] = WEBGL_CONSTANTS.NEAREST_MIPMAP_NEAREST;
THREE_TO_WEBGL[THREE.NearestMipmapLinearFilter] = WEBGL_CONSTANTS.NEAREST_MIPMAP_LINEAR;
THREE_TO_WEBGL[THREE.LinearFilter] = WEBGL_CONSTANTS.LINEAR;
THREE_TO_WEBGL[THREE.LinearMipmapNearestFilter] = WEBGL_CONSTANTS.LINEAR_MIPMAP_NEAREST;
THREE_TO_WEBGL[THREE.LinearMipmapLinearFilter] = WEBGL_CONSTANTS.LINEAR_MIPMAP_LINEAR;
THREE_TO_WEBGL[THREE.ClampToEdgeWrapping] = WEBGL_CONSTANTS.CLAMP_TO_EDGE;
THREE_TO_WEBGL[THREE.RepeatWrapping] = WEBGL_CONSTANTS.REPEAT;
THREE_TO_WEBGL[THREE.MirroredRepeatWrapping] = WEBGL_CONSTANTS.MIRRORED_REPEAT;
var PATH_PROPERTIES = {
  scale: 'scale',
  position: 'translation',
  quaternion: 'rotation',
  morphTargetInfluences: 'weights'
}; //------------------------------------------------------------------------------
// GLTF Exporter
//------------------------------------------------------------------------------

THREE.GLTFExporter = function () {};

THREE.GLTFExporter.prototype = {
  constructor: THREE.GLTFExporter,

  /**
   * Parse scenes and generate GLTF output
   * @param  {THREE.Scene or [THREE.Scenes]} input   THREE.Scene or Array of THREE.Scenes
   * @param  {Function} onDone  Callback on completed
   * @param  {Object} options options
   */
  parse: function parse(input, onDone, options) {
    var DEFAULT_OPTIONS = {
      binary: false,
      trs: false,
      onlyVisible: true,
      truncateDrawRange: true,
      embedImages: true,
      maxTextureSize: Infinity,
      animations: [],
      forcePowerOfTwoTextures: false,
      includeCustomExtensions: false
    };
    options = _Object$assign({}, DEFAULT_OPTIONS, options);

    if (options.animations.length > 0) {
      // Only TRS properties, and not matrices, may be targeted by animation.
      options.trs = true;
    }

    var outputJSON = {
      asset: {
        version: "2.0",
        generator: "THREE.GLTFExporter"
      }
    };
    var byteOffset = 0;
    var buffers = [];
    var pending = [];
    var nodeMap = new _Map();
    var skins = [];
    var extensionsUsed = {};
    var cachedData = {
      meshes: new _Map(),
      attributes: new _Map(),
      attributesNormalized: new _Map(),
      materials: new _Map(),
      textures: new _Map(),
      images: new _Map()
    };
    var cachedCanvas;
    var uids = new _Map();
    var uid = 0;
    /**
     * Assign and return a temporal unique id for an object
     * especially which doesn't have .uuid
     * @param  {Object} object
     * @return {Integer}
     */

    function getUID(object) {
      if (!uids.has(object)) uids.set(object, uid++);
      return uids.get(object);
    }
    /**
     * Compare two arrays
     * @param  {Array} array1 Array 1 to compare
     * @param  {Array} array2 Array 2 to compare
     * @return {Boolean}        Returns true if both arrays are equal
     */


    function equalArray(array1, array2) {
      return array1.length === array2.length && array1.every(function (element, index) {
        return element === array2[index];
      });
    }
    /**
     * Converts a string to an ArrayBuffer.
     * @param  {string} text
     * @return {ArrayBuffer}
     */


    function stringToArrayBuffer(text) {
      if (window.TextEncoder !== undefined) {
        return new TextEncoder().encode(text).buffer;
      }

      var array = new Uint8Array(new ArrayBuffer(text.length));

      for (var i = 0, il = text.length; i < il; i++) {
        var value = text.charCodeAt(i); // Replacing multi-byte character with space(0x20).

        array[i] = value > 0xFF ? 0x20 : value;
      }

      return array.buffer;
    }
    /**
     * Get the min and max vectors from the given attribute
     * @param  {THREE.BufferAttribute} attribute Attribute to find the min/max in range from start to start + count
     * @param  {Integer} start
     * @param  {Integer} count
     * @return {Object} Object containing the `min` and `max` values (As an array of attribute.itemSize components)
     */


    function getMinMax(attribute, start, count) {
      var output = {
        min: new Array(attribute.itemSize).fill(Number.POSITIVE_INFINITY),
        max: new Array(attribute.itemSize).fill(Number.NEGATIVE_INFINITY)
      };

      for (var i = start; i < start + count; i++) {
        for (var a = 0; a < attribute.itemSize; a++) {
          var value = attribute.array[i * attribute.itemSize + a];
          output.min[a] = Math.min(output.min[a], value);
          output.max[a] = Math.max(output.max[a], value);
        }
      }

      return output;
    }
    /**
     * Checks if image size is POT.
     *
     * @param {Image} image The image to be checked.
     * @returns {Boolean} Returns true if image size is POT.
     *
     */


    function isPowerOfTwo(image) {
      return THREE.MathUtils.isPowerOfTwo(image.width) && THREE.MathUtils.isPowerOfTwo(image.height);
    }
    /**
     * Checks if normal attribute values are normalized.
     *
     * @param {THREE.BufferAttribute} normal
     * @returns {Boolean}
     *
     */


    function isNormalizedNormalAttribute(normal) {
      if (cachedData.attributesNormalized.has(normal)) {
        return false;
      }

      var v = new THREE.Vector3();

      for (var i = 0, il = normal.count; i < il; i++) {
        // 0.0005 is from glTF-validator
        if (Math.abs(v.fromArray(normal.array, i * 3).length() - 1.0) > 0.0005) return false;
      }

      return true;
    }
    /**
     * Creates normalized normal buffer attribute.
     *
     * @param {THREE.BufferAttribute} normal
     * @returns {THREE.BufferAttribute}
     *
     */


    function createNormalizedNormalAttribute(normal) {
      if (cachedData.attributesNormalized.has(normal)) {
        return cachedData.attributesNormalized.get(normal);
      }

      var attribute = normal.clone();
      var v = new THREE.Vector3();

      for (var i = 0, il = attribute.count; i < il; i++) {
        v.fromArray(attribute.array, i * 3);

        if (v.x === 0 && v.y === 0 && v.z === 0) {
          // if values can't be normalized set (1, 0, 0)
          v.setX(1.0);
        } else {
          v.normalize();
        }

        v.toArray(attribute.array, i * 3);
      }

      cachedData.attributesNormalized.set(normal, attribute);
      return attribute;
    }
    /**
     * Get the required size + padding for a buffer, rounded to the next 4-byte boundary.
     * https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#data-alignment
     *
     * @param {Integer} bufferSize The size the original buffer.
     * @returns {Integer} new buffer size with required padding.
     *
     */


    function getPaddedBufferSize(bufferSize) {
      return Math.ceil(bufferSize / 4) * 4;
    }
    /**
     * Returns a buffer aligned to 4-byte boundary.
     *
     * @param {ArrayBuffer} arrayBuffer Buffer to pad
     * @param {Integer} paddingByte (Optional)
     * @returns {ArrayBuffer} The same buffer if it's already aligned to 4-byte boundary or a new buffer
     */


    function getPaddedArrayBuffer(arrayBuffer, paddingByte) {
      paddingByte = paddingByte || 0;
      var paddedLength = getPaddedBufferSize(arrayBuffer.byteLength);

      if (paddedLength !== arrayBuffer.byteLength) {
        var array = new Uint8Array(paddedLength);
        array.set(new Uint8Array(arrayBuffer));

        if (paddingByte !== 0) {
          for (var i = arrayBuffer.byteLength; i < paddedLength; i++) {
            array[i] = paddingByte;
          }
        }

        return array.buffer;
      }

      return arrayBuffer;
    }
    /**
     * Serializes a userData.
     *
     * @param {THREE.Object3D|THREE.Material} object
     * @param {Object} gltfProperty
     */


    function serializeUserData(object, gltfProperty) {
      if (_Object$keys(object.userData).length === 0) {
        return;
      }

      try {
        var json = JSON.parse(_JSON$stringify(object.userData));

        if (options.includeCustomExtensions && json.gltfExtensions) {
          if (gltfProperty.extensions === undefined) {
            gltfProperty.extensions = {};
          }

          for (var extensionName in json.gltfExtensions) {
            gltfProperty.extensions[extensionName] = json.gltfExtensions[extensionName];
            extensionsUsed[extensionName] = true;
          }

          delete json.gltfExtensions;
        }

        if (_Object$keys(json).length > 0) {
          gltfProperty.extras = json;
        }
      } catch (error) {
        console.warn('THREE.GLTFExporter: userData of \'' + object.name + '\' ' + 'won\'t be serialized because of JSON.stringify error - ' + error.message);
      }
    }
    /**
     * Applies a texture transform, if present, to the map definition. Requires
     * the KHR_texture_transform extension.
     */


    function applyTextureTransform(mapDef, texture) {
      var didTransform = false;
      var transformDef = {};

      if (texture.offset.x !== 0 || texture.offset.y !== 0) {
        transformDef.offset = texture.offset.toArray();
        didTransform = true;
      }

      if (texture.rotation !== 0) {
        transformDef.rotation = texture.rotation;
        didTransform = true;
      }

      if (texture.repeat.x !== 1 || texture.repeat.y !== 1) {
        transformDef.scale = texture.repeat.toArray();
        didTransform = true;
      }

      if (didTransform) {
        mapDef.extensions = mapDef.extensions || {};
        mapDef.extensions['KHR_texture_transform'] = transformDef;
        extensionsUsed['KHR_texture_transform'] = true;
      }
    }
    /**
     * Process a buffer to append to the default one.
     * @param  {ArrayBuffer} buffer
     * @return {Integer}
     */


    function processBuffer(buffer) {
      if (!outputJSON.buffers) {
        outputJSON.buffers = [{
          byteLength: 0
        }];
      } // All buffers are merged before export.


      buffers.push(buffer);
      return 0;
    }
    /**
     * Process and generate a BufferView
     * @param  {THREE.BufferAttribute} attribute
     * @param  {number} componentType
     * @param  {number} start
     * @param  {number} count
     * @param  {number} target (Optional) Target usage of the BufferView
     * @return {Object}
     */


    function processBufferView(attribute, componentType, start, count, target) {
      if (!outputJSON.bufferViews) {
        outputJSON.bufferViews = [];
      } // Create a new dataview and dump the attribute's array into it


      var componentSize;

      if (componentType === WEBGL_CONSTANTS.UNSIGNED_BYTE) {
        componentSize = 1;
      } else if (componentType === WEBGL_CONSTANTS.UNSIGNED_SHORT) {
        componentSize = 2;
      } else {
        componentSize = 4;
      }

      var byteLength = getPaddedBufferSize(count * attribute.itemSize * componentSize);
      var dataView = new DataView(new ArrayBuffer(byteLength));
      var offset = 0;

      for (var i = start; i < start + count; i++) {
        for (var a = 0; a < attribute.itemSize; a++) {
          var value;

          if (attribute.itemSize > 4) {
            // no support for interleaved data for itemSize > 4
            value = attribute.array[i * attribute.itemSize + a];
          } else {
            if (a === 0) value = attribute.getX(i);else if (a === 1) value = attribute.getY(i);else if (a === 2) value = attribute.getZ(i);else if (a === 3) value = attribute.getW(i);
          }

          if (componentType === WEBGL_CONSTANTS.FLOAT) {
            dataView.setFloat32(offset, value, true);
          } else if (componentType === WEBGL_CONSTANTS.UNSIGNED_INT) {
            dataView.setUint32(offset, value, true);
          } else if (componentType === WEBGL_CONSTANTS.UNSIGNED_SHORT) {
            dataView.setUint16(offset, value, true);
          } else if (componentType === WEBGL_CONSTANTS.UNSIGNED_BYTE) {
            dataView.setUint8(offset, value);
          }

          offset += componentSize;
        }
      }

      var gltfBufferView = {
        buffer: processBuffer(dataView.buffer),
        byteOffset: byteOffset,
        byteLength: byteLength
      };
      if (target !== undefined) gltfBufferView.target = target;

      if (target === WEBGL_CONSTANTS.ARRAY_BUFFER) {
        // Only define byteStride for vertex attributes.
        gltfBufferView.byteStride = attribute.itemSize * componentSize;
      }

      byteOffset += byteLength;
      outputJSON.bufferViews.push(gltfBufferView); // @TODO Merge bufferViews where possible.

      var output = {
        id: outputJSON.bufferViews.length - 1,
        byteLength: 0
      };
      return output;
    }
    /**
     * Process and generate a BufferView from an image Blob.
     * @param {Blob} blob
     * @return {Promise<Integer>}
     */


    function processBufferViewImage(blob) {
      if (!outputJSON.bufferViews) {
        outputJSON.bufferViews = [];
      }

      return new _Promise(function (resolve) {
        var reader = new window.FileReader();
        reader.readAsArrayBuffer(blob);

        reader.onloadend = function () {
          var buffer = getPaddedArrayBuffer(reader.result);
          var bufferView = {
            buffer: processBuffer(buffer),
            byteOffset: byteOffset,
            byteLength: buffer.byteLength
          };
          byteOffset += buffer.byteLength;
          outputJSON.bufferViews.push(bufferView);
          resolve(outputJSON.bufferViews.length - 1);
        };
      });
    }
    /**
     * Process attribute to generate an accessor
     * @param  {THREE.BufferAttribute} attribute Attribute to process
     * @param  {THREE.BufferGeometry} geometry (Optional) Geometry used for truncated draw range
     * @param  {Integer} start (Optional)
     * @param  {Integer} count (Optional)
     * @return {Integer}           Index of the processed accessor on the "accessors" array
     */


    function processAccessor(attribute, geometry, start, count) {
      var types = {
        1: 'SCALAR',
        2: 'VEC2',
        3: 'VEC3',
        4: 'VEC4',
        16: 'MAT4'
      };
      var componentType; // Detect the component type of the attribute array (float, uint or ushort)

      if (attribute.array.constructor === Float32Array) {
        componentType = WEBGL_CONSTANTS.FLOAT;
      } else if (attribute.array.constructor === Uint32Array) {
        componentType = WEBGL_CONSTANTS.UNSIGNED_INT;
      } else if (attribute.array.constructor === Uint16Array) {
        componentType = WEBGL_CONSTANTS.UNSIGNED_SHORT;
      } else if (attribute.array.constructor === Uint8Array) {
        componentType = WEBGL_CONSTANTS.UNSIGNED_BYTE;
      } else {
        throw new Error('THREE.GLTFExporter: Unsupported bufferAttribute component type.');
      }

      if (start === undefined) start = 0;
      if (count === undefined) count = attribute.count; // @TODO Indexed buffer geometry with drawRange not supported yet

      if (options.truncateDrawRange && geometry !== undefined && geometry.index === null) {
        var end = start + count;
        var end2 = geometry.drawRange.count === Infinity ? attribute.count : geometry.drawRange.start + geometry.drawRange.count;
        start = Math.max(start, geometry.drawRange.start);
        count = Math.min(end, end2) - start;
        if (count < 0) count = 0;
      } // Skip creating an accessor if the attribute doesn't have data to export


      if (count === 0) {
        return null;
      }

      var minMax = getMinMax(attribute, start, count);
      var bufferViewTarget; // If geometry isn't provided, don't infer the target usage of the bufferView. For
      // animation samplers, target must not be set.

      if (geometry !== undefined) {
        bufferViewTarget = attribute === geometry.index ? WEBGL_CONSTANTS.ELEMENT_ARRAY_BUFFER : WEBGL_CONSTANTS.ARRAY_BUFFER;
      }

      var bufferView = processBufferView(attribute, componentType, start, count, bufferViewTarget);
      var gltfAccessor = {
        bufferView: bufferView.id,
        byteOffset: bufferView.byteOffset,
        componentType: componentType,
        count: count,
        max: minMax.max,
        min: minMax.min,
        type: types[attribute.itemSize]
      };

      if (attribute.normalized === true) {
        gltfAccessor.normalized = true;
      }

      if (!outputJSON.accessors) {
        outputJSON.accessors = [];
      }

      outputJSON.accessors.push(gltfAccessor);
      return outputJSON.accessors.length - 1;
    }
    /**
     * Process image
     * @param  {Image} image to process
     * @param  {Integer} format of the image (e.g. THREE.RGBFormat, THREE.RGBAFormat etc)
     * @param  {Boolean} flipY before writing out the image
     * @return {Integer}     Index of the processed texture in the "images" array
     */


    function processImage(image, format, flipY) {
      if (!cachedData.images.has(image)) {
        cachedData.images.set(image, {});
      }

      var cachedImages = cachedData.images.get(image);
      var mimeType = format === THREE.RGBAFormat ? 'image/png' : 'image/jpeg';
      var key = mimeType + ":flipY/" + flipY.toString();

      if (cachedImages[key] !== undefined) {
        return cachedImages[key];
      }

      if (!outputJSON.images) {
        outputJSON.images = [];
      }

      var gltfImage = {
        mimeType: mimeType
      };

      if (options.embedImages) {
        var canvas = cachedCanvas = cachedCanvas || document.createElement('canvas');
        canvas.width = Math.min(image.width, options.maxTextureSize);
        canvas.height = Math.min(image.height, options.maxTextureSize);

        if (options.forcePowerOfTwoTextures && !isPowerOfTwo(canvas)) {
          console.warn('GLTFExporter: Resized non-power-of-two image.', image);
          canvas.width = THREE.MathUtils.floorPowerOfTwo(canvas.width);
          canvas.height = THREE.MathUtils.floorPowerOfTwo(canvas.height);
        }

        var ctx = canvas.getContext('2d');

        if (flipY === true) {
          ctx.translate(0, canvas.height);
          ctx.scale(1, -1);
        }

        ctx.drawImage(image, 0, 0, canvas.width, canvas.height);

        if (options.binary === true) {
          pending.push(new _Promise(function (resolve) {
            canvas.toBlob(function (blob) {
              processBufferViewImage(blob).then(function (bufferViewIndex) {
                gltfImage.bufferView = bufferViewIndex;
                resolve();
              });
            }, mimeType);
          }));
        } else {
          gltfImage.uri = canvas.toDataURL(mimeType);
        }
      } else {
        gltfImage.uri = image.src;
      }

      outputJSON.images.push(gltfImage);
      var index = outputJSON.images.length - 1;
      cachedImages[key] = index;
      return index;
    }
    /**
     * Process sampler
     * @param  {Texture} map Texture to process
     * @return {Integer}     Index of the processed texture in the "samplers" array
     */


    function processSampler(map) {
      if (!outputJSON.samplers) {
        outputJSON.samplers = [];
      }

      var gltfSampler = {
        magFilter: THREE_TO_WEBGL[map.magFilter],
        minFilter: THREE_TO_WEBGL[map.minFilter],
        wrapS: THREE_TO_WEBGL[map.wrapS],
        wrapT: THREE_TO_WEBGL[map.wrapT]
      };
      outputJSON.samplers.push(gltfSampler);
      return outputJSON.samplers.length - 1;
    }
    /**
     * Process texture
     * @param  {Texture} map Map to process
     * @return {Integer}     Index of the processed texture in the "textures" array
     */


    function processTexture(map) {
      if (cachedData.textures.has(map)) {
        return cachedData.textures.get(map);
      }

      if (!outputJSON.textures) {
        outputJSON.textures = [];
      }

      var gltfTexture = {
        sampler: processSampler(map),
        source: processImage(map.image, map.format, map.flipY)
      };

      if (map.name) {
        gltfTexture.name = map.name;
      }

      outputJSON.textures.push(gltfTexture);
      var index = outputJSON.textures.length - 1;
      cachedData.textures.set(map, index);
      return index;
    }
    /**
     * Process material
     * @param  {THREE.Material} material Material to process
     * @return {Integer}      Index of the processed material in the "materials" array
     */


    function processMaterial(material) {
      if (cachedData.materials.has(material)) {
        return cachedData.materials.get(material);
      }

      if (material.isShaderMaterial) {
        console.warn('GLTFExporter: THREE.ShaderMaterial not supported.');
        return null;
      }

      if (!outputJSON.materials) {
        outputJSON.materials = [];
      } // @QUESTION Should we avoid including any attribute that has the default value?


      var gltfMaterial = {
        pbrMetallicRoughness: {}
      };

      if (material.isMeshBasicMaterial) {
        gltfMaterial.extensions = {
          KHR_materials_unlit: {}
        };
        extensionsUsed['KHR_materials_unlit'] = true;
      } else if (material.isGLTFSpecularGlossinessMaterial) {
        gltfMaterial.extensions = {
          KHR_materials_pbrSpecularGlossiness: {}
        };
        extensionsUsed['KHR_materials_pbrSpecularGlossiness'] = true;
      } else if (!material.isMeshStandardMaterial) {
        console.warn('GLTFExporter: Use MeshStandardMaterial or MeshBasicMaterial for best results.');
      } // pbrMetallicRoughness.baseColorFactor


      var color = material.color.toArray().concat([material.opacity]);

      if (!equalArray(color, [1, 1, 1, 1])) {
        gltfMaterial.pbrMetallicRoughness.baseColorFactor = color;
      }

      if (material.isMeshStandardMaterial) {
        gltfMaterial.pbrMetallicRoughness.metallicFactor = material.metalness;
        gltfMaterial.pbrMetallicRoughness.roughnessFactor = material.roughness;
      } else if (material.isMeshBasicMaterial) {
        gltfMaterial.pbrMetallicRoughness.metallicFactor = 0.0;
        gltfMaterial.pbrMetallicRoughness.roughnessFactor = 0.9;
      } else {
        gltfMaterial.pbrMetallicRoughness.metallicFactor = 0.5;
        gltfMaterial.pbrMetallicRoughness.roughnessFactor = 0.5;
      } // pbrSpecularGlossiness diffuse, specular and glossiness factor


      if (material.isGLTFSpecularGlossinessMaterial) {
        if (gltfMaterial.pbrMetallicRoughness.baseColorFactor) {
          gltfMaterial.extensions.KHR_materials_pbrSpecularGlossiness.diffuseFactor = gltfMaterial.pbrMetallicRoughness.baseColorFactor;
        }

        var specularFactor = [1, 1, 1];
        material.specular.toArray(specularFactor, 0);
        gltfMaterial.extensions.KHR_materials_pbrSpecularGlossiness.specularFactor = specularFactor;
        gltfMaterial.extensions.KHR_materials_pbrSpecularGlossiness.glossinessFactor = material.glossiness;
      } // pbrMetallicRoughness.metallicRoughnessTexture


      if (material.metalnessMap || material.roughnessMap) {
        if (material.metalnessMap === material.roughnessMap) {
          var metalRoughMapDef = {
            index: processTexture(material.metalnessMap)
          };
          applyTextureTransform(metalRoughMapDef, material.metalnessMap);
          gltfMaterial.pbrMetallicRoughness.metallicRoughnessTexture = metalRoughMapDef;
        } else {
          console.warn('THREE.GLTFExporter: Ignoring metalnessMap and roughnessMap because they are not the same Texture.');
        }
      } // pbrMetallicRoughness.baseColorTexture or pbrSpecularGlossiness diffuseTexture


      if (material.map) {
        var baseColorMapDef = {
          index: processTexture(material.map)
        };
        applyTextureTransform(baseColorMapDef, material.map);

        if (material.isGLTFSpecularGlossinessMaterial) {
          gltfMaterial.extensions.KHR_materials_pbrSpecularGlossiness.diffuseTexture = baseColorMapDef;
        }

        gltfMaterial.pbrMetallicRoughness.baseColorTexture = baseColorMapDef;
      } // pbrSpecularGlossiness specular map


      if (material.isGLTFSpecularGlossinessMaterial && material.specularMap) {
        var specularMapDef = {
          index: processTexture(material.specularMap)
        };
        applyTextureTransform(specularMapDef, material.specularMap);
        gltfMaterial.extensions.KHR_materials_pbrSpecularGlossiness.specularGlossinessTexture = specularMapDef;
      }

      if (material.emissive) {
        // emissiveFactor
        var emissive = material.emissive.clone().multiplyScalar(material.emissiveIntensity).toArray();

        if (!equalArray(emissive, [0, 0, 0])) {
          gltfMaterial.emissiveFactor = emissive;
        } // emissiveTexture


        if (material.emissiveMap) {
          var emissiveMapDef = {
            index: processTexture(material.emissiveMap)
          };
          applyTextureTransform(emissiveMapDef, material.emissiveMap);
          gltfMaterial.emissiveTexture = emissiveMapDef;
        }
      } // normalTexture


      if (material.normalMap) {
        var normalMapDef = {
          index: processTexture(material.normalMap)
        };

        if (material.normalScale && material.normalScale.x !== -1) {
          if (material.normalScale.x !== material.normalScale.y) {
            console.warn('THREE.GLTFExporter: Normal scale components are different, ignoring Y and exporting X.');
          }

          normalMapDef.scale = material.normalScale.x;
        }

        applyTextureTransform(normalMapDef, material.normalMap);
        gltfMaterial.normalTexture = normalMapDef;
      } // occlusionTexture


      if (material.aoMap) {
        var occlusionMapDef = {
          index: processTexture(material.aoMap),
          texCoord: 1
        };

        if (material.aoMapIntensity !== 1.0) {
          occlusionMapDef.strength = material.aoMapIntensity;
        }

        applyTextureTransform(occlusionMapDef, material.aoMap);
        gltfMaterial.occlusionTexture = occlusionMapDef;
      } // alphaMode


      if (material.transparent) {
        gltfMaterial.alphaMode = 'BLEND';
      } else {
        if (material.alphaTest > 0.0) {
          gltfMaterial.alphaMode = 'MASK';
          gltfMaterial.alphaCutoff = material.alphaTest;
        }
      } // doubleSided


      if (material.side === THREE.DoubleSide) {
        gltfMaterial.doubleSided = true;
      }

      if (material.name !== '') {
        gltfMaterial.name = material.name;
      }

      serializeUserData(material, gltfMaterial);
      outputJSON.materials.push(gltfMaterial);
      var index = outputJSON.materials.length - 1;
      cachedData.materials.set(material, index);
      return index;
    }
    /**
     * Process mesh
     * @param  {THREE.Mesh} mesh Mesh to process
     * @return {Integer}      Index of the processed mesh in the "meshes" array
     */


    function processMesh(mesh) {
      var meshCacheKeyParts = [mesh.geometry.uuid];

      if (_Array$isArray(mesh.material)) {
        for (var i = 0, l = mesh.material.length; i < l; i++) {
          meshCacheKeyParts.push(mesh.material[i].uuid);
        }
      } else {
        meshCacheKeyParts.push(mesh.material.uuid);
      }

      var meshCacheKey = meshCacheKeyParts.join(':');

      if (cachedData.meshes.has(meshCacheKey)) {
        return cachedData.meshes.get(meshCacheKey);
      }

      var geometry = mesh.geometry;
      var mode; // Use the correct mode

      if (mesh.isLineSegments) {
        mode = WEBGL_CONSTANTS.LINES;
      } else if (mesh.isLineLoop) {
        mode = WEBGL_CONSTANTS.LINE_LOOP;
      } else if (mesh.isLine) {
        mode = WEBGL_CONSTANTS.LINE_STRIP;
      } else if (mesh.isPoints) {
        mode = WEBGL_CONSTANTS.POINTS;
      } else {
        mode = mesh.material.wireframe ? WEBGL_CONSTANTS.LINES : WEBGL_CONSTANTS.TRIANGLES;
      }

      if (!geometry.isBufferGeometry) {
        console.warn('GLTFExporter: Exporting THREE.Geometry will increase file size. Use THREE.BufferGeometry instead.');
        geometry = new THREE.BufferGeometry().setFromObject(mesh);
      }

      var gltfMesh = {};
      var attributes = {};
      var primitives = [];
      var targets = []; // Conversion between attributes names in threejs and gltf spec

      var nameConversion = {
        uv: 'TEXCOORD_0',
        uv2: 'TEXCOORD_1',
        color: 'COLOR_0',
        skinWeight: 'WEIGHTS_0',
        skinIndex: 'JOINTS_0'
      };
      var originalNormal = geometry.getAttribute('normal');

      if (originalNormal !== undefined && !isNormalizedNormalAttribute(originalNormal)) {
        console.warn('THREE.GLTFExporter: Creating normalized normal attribute from the non-normalized one.');
        geometry.setAttribute('normal', createNormalizedNormalAttribute(originalNormal));
      } // @QUESTION Detect if .vertexColors = true?
      // For every attribute create an accessor


      var modifiedAttribute = null;

      for (var attributeName in geometry.attributes) {
        // Ignore morph target attributes, which are exported later.
        if (attributeName.substr(0, 5) === 'morph') continue;
        var attribute = geometry.attributes[attributeName];
        attributeName = nameConversion[attributeName] || attributeName.toUpperCase(); // Prefix all geometry attributes except the ones specifically
        // listed in the spec; non-spec attributes are considered custom.

        var validVertexAttributes = /^(POSITION|NORMAL|TANGENT|TEXCOORD_\d+|COLOR_\d+|JOINTS_\d+|WEIGHTS_\d+)$/;

        if (!validVertexAttributes.test(attributeName)) {
          attributeName = '_' + attributeName;
        }

        if (cachedData.attributes.has(getUID(attribute))) {
          attributes[attributeName] = cachedData.attributes.get(getUID(attribute));
          continue;
        } // JOINTS_0 must be UNSIGNED_BYTE or UNSIGNED_SHORT.


        modifiedAttribute = null;
        var array = attribute.array;

        if (attributeName === 'JOINTS_0' && !(array instanceof Uint16Array) && !(array instanceof Uint8Array)) {
          console.warn('GLTFExporter: Attribute "skinIndex" converted to type UNSIGNED_SHORT.');
          modifiedAttribute = new THREE.BufferAttribute(new Uint16Array(array), attribute.itemSize, attribute.normalized);
        }

        var accessor = processAccessor(modifiedAttribute || attribute, geometry);

        if (accessor !== null) {
          attributes[attributeName] = accessor;
          cachedData.attributes.set(getUID(attribute), accessor);
        }
      }

      if (originalNormal !== undefined) geometry.setAttribute('normal', originalNormal); // Skip if no exportable attributes found

      if (_Object$keys(attributes).length === 0) {
        return null;
      } // Morph targets


      if (mesh.morphTargetInfluences !== undefined && mesh.morphTargetInfluences.length > 0) {
        var weights = [];
        var targetNames = [];
        var reverseDictionary = {};

        if (mesh.morphTargetDictionary !== undefined) {
          for (var key in mesh.morphTargetDictionary) {
            reverseDictionary[mesh.morphTargetDictionary[key]] = key;
          }
        }

        for (var i = 0; i < mesh.morphTargetInfluences.length; ++i) {
          var target = {};
          var warned = false;

          for (var attributeName in geometry.morphAttributes) {
            // glTF 2.0 morph supports only POSITION/NORMAL/TANGENT.
            // Three.js doesn't support TANGENT yet.
            if (attributeName !== 'position' && attributeName !== 'normal') {
              if (!warned) {
                console.warn('GLTFExporter: Only POSITION and NORMAL morph are supported.');
                warned = true;
              }

              continue;
            }

            var attribute = geometry.morphAttributes[attributeName][i];
            var gltfAttributeName = attributeName.toUpperCase(); // Three.js morph attribute has absolute values while the one of glTF has relative values.
            //
            // glTF 2.0 Specification:
            // https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#morph-targets

            var baseAttribute = geometry.attributes[attributeName];

            if (cachedData.attributes.has(getUID(attribute))) {
              target[gltfAttributeName] = cachedData.attributes.get(getUID(attribute));
              continue;
            } // Clones attribute not to override


            var relativeAttribute = attribute.clone();

            if (!geometry.morphTargetsRelative) {
              for (var j = 0, jl = attribute.count; j < jl; j++) {
                relativeAttribute.setXYZ(j, attribute.getX(j) - baseAttribute.getX(j), attribute.getY(j) - baseAttribute.getY(j), attribute.getZ(j) - baseAttribute.getZ(j));
              }
            }

            target[gltfAttributeName] = processAccessor(relativeAttribute, geometry);
            cachedData.attributes.set(getUID(baseAttribute), target[gltfAttributeName]);
          }

          targets.push(target);
          weights.push(mesh.morphTargetInfluences[i]);
          if (mesh.morphTargetDictionary !== undefined) targetNames.push(reverseDictionary[i]);
        }

        gltfMesh.weights = weights;

        if (targetNames.length > 0) {
          gltfMesh.extras = {};
          gltfMesh.extras.targetNames = targetNames;
        }
      }

      var isMultiMaterial = _Array$isArray(mesh.material);

      if (isMultiMaterial && geometry.groups.length === 0) return null;
      var materials = isMultiMaterial ? mesh.material : [mesh.material];
      var groups = isMultiMaterial ? geometry.groups : [{
        materialIndex: 0,
        start: undefined,
        count: undefined
      }];

      for (var i = 0, il = groups.length; i < il; i++) {
        var primitive = {
          mode: mode,
          attributes: attributes
        };
        serializeUserData(geometry, primitive);
        if (targets.length > 0) primitive.targets = targets;

        if (geometry.index !== null) {
          var cacheKey = getUID(geometry.index);

          if (groups[i].start !== undefined || groups[i].count !== undefined) {
            cacheKey += ':' + groups[i].start + ':' + groups[i].count;
          }

          if (cachedData.attributes.has(cacheKey)) {
            primitive.indices = cachedData.attributes.get(cacheKey);
          } else {
            primitive.indices = processAccessor(geometry.index, geometry, groups[i].start, groups[i].count);
            cachedData.attributes.set(cacheKey, primitive.indices);
          }

          if (primitive.indices === null) delete primitive.indices;
        }

        var material = processMaterial(materials[groups[i].materialIndex]);

        if (material !== null) {
          primitive.material = material;
        }

        primitives.push(primitive);
      }

      gltfMesh.primitives = primitives;

      if (!outputJSON.meshes) {
        outputJSON.meshes = [];
      }

      outputJSON.meshes.push(gltfMesh);
      var index = outputJSON.meshes.length - 1;
      cachedData.meshes.set(meshCacheKey, index);
      return index;
    }
    /**
     * Process camera
     * @param  {THREE.Camera} camera Camera to process
     * @return {Integer}      Index of the processed mesh in the "camera" array
     */


    function processCamera(camera) {
      if (!outputJSON.cameras) {
        outputJSON.cameras = [];
      }

      var isOrtho = camera.isOrthographicCamera;
      var gltfCamera = {
        type: isOrtho ? 'orthographic' : 'perspective'
      };

      if (isOrtho) {
        gltfCamera.orthographic = {
          xmag: camera.right * 2,
          ymag: camera.top * 2,
          zfar: camera.far <= 0 ? 0.001 : camera.far,
          znear: camera.near < 0 ? 0 : camera.near
        };
      } else {
        gltfCamera.perspective = {
          aspectRatio: camera.aspect,
          yfov: THREE.MathUtils.degToRad(camera.fov),
          zfar: camera.far <= 0 ? 0.001 : camera.far,
          znear: camera.near < 0 ? 0 : camera.near
        };
      }

      if (camera.name !== '') {
        gltfCamera.name = camera.type;
      }

      outputJSON.cameras.push(gltfCamera);
      return outputJSON.cameras.length - 1;
    }
    /**
     * Creates glTF animation entry from AnimationClip object.
     *
     * Status:
     * - Only properties listed in PATH_PROPERTIES may be animated.
     *
     * @param {THREE.AnimationClip} clip
     * @param {THREE.Object3D} root
     * @return {number}
     */


    function processAnimation(clip, root) {
      if (!outputJSON.animations) {
        outputJSON.animations = [];
      }

      clip = THREE.GLTFExporter.Utils.mergeMorphTargetTracks(clip.clone(), root);
      var tracks = clip.tracks;
      var channels = [];
      var samplers = [];

      for (var i = 0; i < tracks.length; ++i) {
        var track = tracks[i];
        var trackBinding = THREE.PropertyBinding.parseTrackName(track.name);
        var trackNode = THREE.PropertyBinding.findNode(root, trackBinding.nodeName);
        var trackProperty = PATH_PROPERTIES[trackBinding.propertyName];

        if (trackBinding.objectName === 'bones') {
          if (trackNode.isSkinnedMesh === true) {
            trackNode = trackNode.skeleton.getBoneByName(trackBinding.objectIndex);
          } else {
            trackNode = undefined;
          }
        }

        if (!trackNode || !trackProperty) {
          console.warn('THREE.GLTFExporter: Could not export animation track "%s".', track.name);
          return null;
        }

        var inputItemSize = 1;
        var outputItemSize = track.values.length / track.times.length;

        if (trackProperty === PATH_PROPERTIES.morphTargetInfluences) {
          outputItemSize /= trackNode.morphTargetInfluences.length;
        }

        var interpolation; // @TODO export CubicInterpolant(InterpolateSmooth) as CUBICSPLINE
        // Detecting glTF cubic spline interpolant by checking factory method's special property
        // GLTFCubicSplineInterpolant is a custom interpolant and track doesn't return
        // valid value from .getInterpolation().

        if (track.createInterpolant.isInterpolantFactoryMethodGLTFCubicSpline === true) {
          interpolation = 'CUBICSPLINE'; // itemSize of CUBICSPLINE keyframe is 9
          // (VEC3 * 3: inTangent, splineVertex, and outTangent)
          // but needs to be stored as VEC3 so dividing by 3 here.

          outputItemSize /= 3;
        } else if (track.getInterpolation() === THREE.InterpolateDiscrete) {
          interpolation = 'STEP';
        } else {
          interpolation = 'LINEAR';
        }

        samplers.push({
          input: processAccessor(new THREE.BufferAttribute(track.times, inputItemSize)),
          output: processAccessor(new THREE.BufferAttribute(track.values, outputItemSize)),
          interpolation: interpolation
        });
        channels.push({
          sampler: samplers.length - 1,
          target: {
            node: nodeMap.get(trackNode),
            path: trackProperty
          }
        });
      }

      outputJSON.animations.push({
        name: clip.name || 'clip_' + outputJSON.animations.length,
        samplers: samplers,
        channels: channels
      });
      return outputJSON.animations.length - 1;
    }

    function processSkin(object) {
      var node = outputJSON.nodes[nodeMap.get(object)];
      var skeleton = object.skeleton;
      if (skeleton === undefined) return null;
      var rootJoint = object.skeleton.bones[0];
      if (rootJoint === undefined) return null;
      var joints = [];
      var inverseBindMatrices = new Float32Array(skeleton.bones.length * 16);

      for (var i = 0; i < skeleton.bones.length; ++i) {
        joints.push(nodeMap.get(skeleton.bones[i]));
        skeleton.boneInverses[i].toArray(inverseBindMatrices, i * 16);
      }

      if (outputJSON.skins === undefined) {
        outputJSON.skins = [];
      }

      outputJSON.skins.push({
        inverseBindMatrices: processAccessor(new THREE.BufferAttribute(inverseBindMatrices, 16)),
        joints: joints,
        skeleton: nodeMap.get(rootJoint)
      });
      var skinIndex = node.skin = outputJSON.skins.length - 1;
      return skinIndex;
    }

    function processLight(light) {
      var lightDef = {};
      if (light.name) lightDef.name = light.name;
      lightDef.color = light.color.toArray();
      lightDef.intensity = light.intensity;

      if (light.isDirectionalLight) {
        lightDef.type = 'directional';
      } else if (light.isPointLight) {
        lightDef.type = 'point';
        if (light.distance > 0) lightDef.range = light.distance;
      } else if (light.isSpotLight) {
        lightDef.type = 'spot';
        if (light.distance > 0) lightDef.range = light.distance;
        lightDef.spot = {};
        lightDef.spot.innerConeAngle = (light.penumbra - 1.0) * light.angle * -1.0;
        lightDef.spot.outerConeAngle = light.angle;
      }

      if (light.decay !== undefined && light.decay !== 2) {
        console.warn('THREE.GLTFExporter: Light decay may be lost. glTF is physically-based, ' + 'and expects light.decay=2.');
      }

      if (light.target && (light.target.parent !== light || light.target.position.x !== 0 || light.target.position.y !== 0 || light.target.position.z !== -1)) {
        console.warn('THREE.GLTFExporter: Light direction may be lost. For best results, ' + 'make light.target a child of the light with position 0,0,-1.');
      }

      var lights = outputJSON.extensions['KHR_lights_punctual'].lights;
      lights.push(lightDef);
      return lights.length - 1;
    }
    /**
     * Process Object3D node
     * @param  {THREE.Object3D} node Object3D to processNode
     * @return {Integer}      Index of the node in the nodes list
     */


    function processNode(object) {
      if (!outputJSON.nodes) {
        outputJSON.nodes = [];
      }

      var gltfNode = {};

      if (options.trs) {
        var rotation = object.quaternion.toArray();
        var position = object.position.toArray();
        var scale = object.scale.toArray();

        if (!equalArray(rotation, [0, 0, 0, 1])) {
          gltfNode.rotation = rotation;
        }

        if (!equalArray(position, [0, 0, 0])) {
          gltfNode.translation = position;
        }

        if (!equalArray(scale, [1, 1, 1])) {
          gltfNode.scale = scale;
        }
      } else {
        if (object.matrixAutoUpdate) {
          object.updateMatrix();
        }

        if (!equalArray(object.matrix.elements, [1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1])) {
          gltfNode.matrix = object.matrix.elements;
        }
      } // We don't export empty strings name because it represents no-name in Three.js.


      if (object.name !== '') {
        gltfNode.name = String(object.name);
      }

      serializeUserData(object, gltfNode);

      if (object.isMesh || object.isLine || object.isPoints) {
        var mesh = processMesh(object);

        if (mesh !== null) {
          gltfNode.mesh = mesh;
        }
      } else if (object.isCamera) {
        gltfNode.camera = processCamera(object);
      } else if (object.isDirectionalLight || object.isPointLight || object.isSpotLight) {
        if (!extensionsUsed['KHR_lights_punctual']) {
          outputJSON.extensions = outputJSON.extensions || {};
          outputJSON.extensions['KHR_lights_punctual'] = {
            lights: []
          };
          extensionsUsed['KHR_lights_punctual'] = true;
        }

        gltfNode.extensions = gltfNode.extensions || {};
        gltfNode.extensions['KHR_lights_punctual'] = {
          light: processLight(object)
        };
      } else if (object.isLight) {
        console.warn('THREE.GLTFExporter: Only directional, point, and spot lights are supported.', object);
        return null;
      }

      if (object.isSkinnedMesh) {
        skins.push(object);
      }

      if (object.children.length > 0) {
        var children = [];

        for (var i = 0, l = object.children.length; i < l; i++) {
          var child = object.children[i];

          if (child.visible || options.onlyVisible === false) {
            var node = processNode(child);

            if (node !== null) {
              children.push(node);
            }
          }
        }

        if (children.length > 0) {
          gltfNode.children = children;
        }
      }

      outputJSON.nodes.push(gltfNode);
      var nodeIndex = outputJSON.nodes.length - 1;
      nodeMap.set(object, nodeIndex);
      return nodeIndex;
    }
    /**
     * Process Scene
     * @param  {THREE.Scene} node Scene to process
     */


    function processScene(scene) {
      if (!outputJSON.scenes) {
        outputJSON.scenes = [];
        outputJSON.scene = 0;
      }

      var gltfScene = {};

      if (scene.name !== '') {
        gltfScene.name = scene.name;
      }

      outputJSON.scenes.push(gltfScene);
      var nodes = [];

      for (var i = 0, l = scene.children.length; i < l; i++) {
        var child = scene.children[i];

        if (child.visible || options.onlyVisible === false) {
          var node = processNode(child);

          if (node !== null) {
            nodes.push(node);
          }
        }
      }

      if (nodes.length > 0) {
        gltfScene.nodes = nodes;
      }

      serializeUserData(scene, gltfScene);
    }
    /**
     * Creates a THREE.Scene to hold a list of objects and parse it
     * @param  {Array} objects List of objects to process
     */


    function processObjects(objects) {
      var scene = new THREE.Scene();
      scene.name = 'AuxScene';

      for (var i = 0; i < objects.length; i++) {
        // We push directly to children instead of calling `add` to prevent
        // modify the .parent and break its original scene and hierarchy
        scene.children.push(objects[i]);
      }

      processScene(scene);
    }

    function processInput(input) {
      input = input instanceof Array ? input : [input];
      var objectsWithoutScene = [];

      for (var i = 0; i < input.length; i++) {
        if (input[i] instanceof THREE.Scene) {
          processScene(input[i]);
        } else {
          objectsWithoutScene.push(input[i]);
        }
      }

      if (objectsWithoutScene.length > 0) {
        processObjects(objectsWithoutScene);
      }

      for (var i = 0; i < skins.length; ++i) {
        processSkin(skins[i]);
      }

      for (var i = 0; i < options.animations.length; ++i) {
        processAnimation(options.animations[i], input[0]);
      }
    }

    processInput(input);

    _Promise.all(pending).then(function () {
      // Merge buffers.
      var blob = new Blob(buffers, {
        type: 'application/octet-stream'
      }); // Declare extensions.

      var extensionsUsedList = _Object$keys(extensionsUsed);

      if (extensionsUsedList.length > 0) outputJSON.extensionsUsed = extensionsUsedList; // Update bytelength of the single buffer.

      if (outputJSON.buffers && outputJSON.buffers.length > 0) outputJSON.buffers[0].byteLength = blob.size;

      if (options.binary === true) {
        // https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#glb-file-format-specification
        var GLB_HEADER_BYTES = 12;
        var GLB_HEADER_MAGIC = 0x46546C67;
        var GLB_VERSION = 2;
        var GLB_CHUNK_PREFIX_BYTES = 8;
        var GLB_CHUNK_TYPE_JSON = 0x4E4F534A;
        var GLB_CHUNK_TYPE_BIN = 0x004E4942;
        var reader = new window.FileReader();
        reader.readAsArrayBuffer(blob);

        reader.onloadend = function () {
          // Binary chunk.
          var binaryChunk = getPaddedArrayBuffer(reader.result);
          var binaryChunkPrefix = new DataView(new ArrayBuffer(GLB_CHUNK_PREFIX_BYTES));
          binaryChunkPrefix.setUint32(0, binaryChunk.byteLength, true);
          binaryChunkPrefix.setUint32(4, GLB_CHUNK_TYPE_BIN, true); // JSON chunk.

          var jsonChunk = getPaddedArrayBuffer(stringToArrayBuffer(_JSON$stringify(outputJSON)), 0x20);
          var jsonChunkPrefix = new DataView(new ArrayBuffer(GLB_CHUNK_PREFIX_BYTES));
          jsonChunkPrefix.setUint32(0, jsonChunk.byteLength, true);
          jsonChunkPrefix.setUint32(4, GLB_CHUNK_TYPE_JSON, true); // GLB header.

          var header = new ArrayBuffer(GLB_HEADER_BYTES);
          var headerView = new DataView(header);
          headerView.setUint32(0, GLB_HEADER_MAGIC, true);
          headerView.setUint32(4, GLB_VERSION, true);
          var totalByteLength = GLB_HEADER_BYTES + jsonChunkPrefix.byteLength + jsonChunk.byteLength + binaryChunkPrefix.byteLength + binaryChunk.byteLength;
          headerView.setUint32(8, totalByteLength, true);
          var glbBlob = new Blob([header, jsonChunkPrefix, jsonChunk, binaryChunkPrefix, binaryChunk], {
            type: 'application/octet-stream'
          });
          var glbReader = new window.FileReader();
          glbReader.readAsArrayBuffer(glbBlob);

          glbReader.onloadend = function () {
            onDone(glbReader.result);
          };
        };
      } else {
        if (outputJSON.buffers && outputJSON.buffers.length > 0) {
          var reader = new window.FileReader();
          reader.readAsDataURL(blob);

          reader.onloadend = function () {
            var base64data = reader.result;
            outputJSON.buffers[0].uri = base64data;
            onDone(outputJSON);
          };
        } else {
          onDone(outputJSON);
        }
      }
    });
  }
};
THREE.GLTFExporter.Utils = {
  insertKeyframe: function insertKeyframe(track, time) {
    var tolerance = 0.001; // 1ms

    var valueSize = track.getValueSize();
    var times = new track.TimeBufferType(track.times.length + 1);
    var values = new track.ValueBufferType(track.values.length + valueSize);
    var interpolant = track.createInterpolant(new track.ValueBufferType(valueSize));
    var index;

    if (track.times.length === 0) {
      times[0] = time;

      for (var i = 0; i < valueSize; i++) {
        values[i] = 0;
      }

      index = 0;
    } else if (time < track.times[0]) {
      if (Math.abs(track.times[0] - time) < tolerance) return 0;
      times[0] = time;
      times.set(track.times, 1);
      values.set(interpolant.evaluate(time), 0);
      values.set(track.values, valueSize);
      index = 0;
    } else if (time > track.times[track.times.length - 1]) {
      if (Math.abs(track.times[track.times.length - 1] - time) < tolerance) {
        return track.times.length - 1;
      }

      times[times.length - 1] = time;
      times.set(track.times, 0);
      values.set(track.values, 0);
      values.set(interpolant.evaluate(time), track.values.length);
      index = times.length - 1;
    } else {
      for (var i = 0; i < track.times.length; i++) {
        if (Math.abs(track.times[i] - time) < tolerance) return i;

        if (track.times[i] < time && track.times[i + 1] > time) {
          times.set(track.times.slice(0, i + 1), 0);
          times[i + 1] = time;
          times.set(track.times.slice(i + 1), i + 2);
          values.set(track.values.slice(0, (i + 1) * valueSize), 0);
          values.set(interpolant.evaluate(time), (i + 1) * valueSize);
          values.set(track.values.slice((i + 1) * valueSize), (i + 2) * valueSize);
          index = i + 1;
          break;
        }
      }
    }

    track.times = times;
    track.values = values;
    return index;
  },
  mergeMorphTargetTracks: function mergeMorphTargetTracks(clip, root) {
    var tracks = [];
    var mergedTracks = {};
    var sourceTracks = clip.tracks;

    for (var i = 0; i < sourceTracks.length; ++i) {
      var sourceTrack = sourceTracks[i];
      var sourceTrackBinding = THREE.PropertyBinding.parseTrackName(sourceTrack.name);
      var sourceTrackNode = THREE.PropertyBinding.findNode(root, sourceTrackBinding.nodeName);

      if (sourceTrackBinding.propertyName !== 'morphTargetInfluences' || sourceTrackBinding.propertyIndex === undefined) {
        // Tracks that don't affect morph targets, or that affect all morph targets together, can be left as-is.
        tracks.push(sourceTrack);
        continue;
      }

      if (sourceTrack.createInterpolant !== sourceTrack.InterpolantFactoryMethodDiscrete && sourceTrack.createInterpolant !== sourceTrack.InterpolantFactoryMethodLinear) {
        if (sourceTrack.createInterpolant.isInterpolantFactoryMethodGLTFCubicSpline) {
          // This should never happen, because glTF morph target animations
          // affect all targets already.
          throw new Error('THREE.GLTFExporter: Cannot merge tracks with glTF CUBICSPLINE interpolation.');
        }

        console.warn('THREE.GLTFExporter: Morph target interpolation mode not yet supported. Using LINEAR instead.');
        sourceTrack = sourceTrack.clone();
        sourceTrack.setInterpolation(THREE.InterpolateLinear);
      }

      var targetCount = sourceTrackNode.morphTargetInfluences.length;
      var targetIndex = sourceTrackNode.morphTargetDictionary[sourceTrackBinding.propertyIndex];

      if (targetIndex === undefined) {
        throw new Error('THREE.GLTFExporter: Morph target name not found: ' + sourceTrackBinding.propertyIndex);
      }

      var mergedTrack; // If this is the first time we've seen this object, create a new
      // track to store merged keyframe data for each morph target.

      if (mergedTracks[sourceTrackNode.uuid] === undefined) {
        mergedTrack = sourceTrack.clone();
        var values = new mergedTrack.ValueBufferType(targetCount * mergedTrack.times.length);

        for (var j = 0; j < mergedTrack.times.length; j++) {
          values[j * targetCount + targetIndex] = mergedTrack.values[j];
        } // We need to take into consideration the intended target node
        // of our original un-merged morphTarget animation.


        mergedTrack.name = sourceTrackBinding.nodeName + '.morphTargetInfluences';
        mergedTrack.values = values;
        mergedTracks[sourceTrackNode.uuid] = mergedTrack;
        tracks.push(mergedTrack);
        continue;
      }

      var sourceInterpolant = sourceTrack.createInterpolant(new sourceTrack.ValueBufferType(1));
      mergedTrack = mergedTracks[sourceTrackNode.uuid]; // For every existing keyframe of the merged track, write a (possibly
      // interpolated) value from the source track.

      for (var j = 0; j < mergedTrack.times.length; j++) {
        mergedTrack.values[j * targetCount + targetIndex] = sourceInterpolant.evaluate(mergedTrack.times[j]);
      } // For every existing keyframe of the source track, write a (possibly
      // new) keyframe to the merged track. Values from the previous loop may
      // be written again, but keyframes are de-duplicated.


      for (var j = 0; j < sourceTrack.times.length; j++) {
        var keyframeIndex = this.insertKeyframe(mergedTrack, sourceTrack.times[j]);
        mergedTrack.values[keyframeIndex * targetCount + targetIndex] = sourceTrack.values[j];
      }
    }

    clip.tracks = tracks;
    return clip;
  }
};