/**
 * @author Kyle-Larson https://github.com/Kyle-Larson
 * @author Takahiro https://github.com/takahirox
 * @author Lewy Blue https://github.com/looeee
 *
 * Loader loads FBX file and generates Group representing FBX scene.
 * Requires FBX file to be >= 7.0 and in ASCII or >= 6400 in Binary format
 * Versions lower than this may load but will probably have errors
 *
 * Needs Support:
 *  Morph normals / blend shape normals
 *
 * FBX format references:
 * 	https://wiki.blender.org/index.php/User:Mont29/Foundation/FBX_File_Structure
 * 	http://help.autodesk.com/view/FBX/2017/ENU/?guid=__cpp_ref_index_html (C++ SDK reference)
 *
 * 	Binary format specification:
 *		https://code.blender.org/2013/08/fbx-binary-file-format-specification/
 */


THREE.FBXLoader = (function () {

    var fbxTree;
    var connections;
    var sceneGraph;

    function FBXLoader(manager) {

        this.manager = (manager !== undefined) ? manager : THREE.DefaultLoadingManager;

    }

    FBXLoader.prototype = {

        constructor: FBXLoader,

        crossOrigin: 'anonymous',

        load: function (url, onLoad, onProgress, onError) {
            var self = this;

            var resourceDirectory = THREE.LoaderUtils.extractUrlBase(url);

            var loader = new THREE.FileLoader(this.manager);
            loader.setResponseType('arraybuffer');
            loader.load(url, function (buffer) {

                try {

                    var scene = self.parse(buffer, resourceDirectory);
                    onLoad(scene);

                } catch (error) {

                    setTimeout(function () {

                        if (onError) onError(error);

                        self.manager.itemError(url);

                    }, 0);

                }

            }, onProgress, onError);
        },

        setCrossOrigin: function (value) {

            this.crossOrigin = value;
            return this;

        },

        parse: function (FBXBuffer, resourceDirectory) {

            if (isFbxFormatBinary(FBXBuffer)) {

                fbxTree = new BinaryParser().parse(FBXBuffer);

            } else {

                var FBXText = convertArrayBufferToString(FBXBuffer);

                if (!isFbxFormatASCII(FBXText)) {

                    throw new Error('THREE.FBXLoader: Unknown format.');

                }

                if (getFbxVersion(FBXText) < 7000) {

                    throw new Error('THREE.FBXLoader: FBX version not supported, FileVersion: ' + getFbxVersion(FBXText));

                }

                fbxTree = new TextParser().parse(FBXText);

            }

            //console.log( FBXTree );

            var textureLoader = new THREE.TextureLoader(this.manager).setPath(resourceDirectory).setCrossOrigin(this.crossOrigin);

            return new FBXTreeParser(textureLoader).parse(fbxTree);

        }

    };

    // Parse the FBXTree object returned by the BinaryParser or TextParser and return a THREE.Group
    function FBXTreeParser(textureLoader) {

        this.textureLoader = textureLoader;

    }

    FBXTreeParser.prototype = {

        constructor: FBXTreeParser,

        parse: function () {

            connections = this.parseConnections();

            var images = this.parseImages();
            var textures = this.parseTextures(images);
            var materials = this.parseMaterials(textures);
            var deformers = this.parseDeformers();
            var geometryMap = new GeometryParser().parse(deformers);

            this.parseScene(deformers, geometryMap, materials);

            return sceneGraph;

        },

        // Parses FBXTree.Connections which holds parent-child connections between objects (e.g. material -> texture, model->geometry )
        // and details the connection type
        parseConnections: function () {

            var connectionMap = new Map();

            if ('Connections' in fbxTree) {

                var rawConnections = fbxTree.Connections.connections;

                rawConnections.forEach(function (rawConnection) {

                    var fromID = rawConnection[0];
                    var toID = rawConnection[1];
                    var relationship = rawConnection[2];

                    if (!connectionMap.has(fromID)) {

                        connectionMap.set(fromID, {
                            parents: [],
                            children: []
                        });

                    }

                    var parentRelationship = { ID: toID, relationship: relationship };
                    connectionMap.get(fromID).parents.push(parentRelationship);

                    if (!connectionMap.has(toID)) {

                        connectionMap.set(toID, {
                            parents: [],
                            children: []
                        });

                    }

                    var childRelationship = { ID: fromID, relationship: relationship };
                    connectionMap.get(toID).children.push(childRelationship);

                });

            }

            return connectionMap;

        },

        // Parse FBXTree.Objects.Video for embedded image data
        // These images are connected to textures in FBXTree.Objects.Textures
        // via FBXTree.Connections.
        parseImages: function () {

            var images = {};
            var blobs = {};

            if ('Video' in fbxTree.Objects) {

                var videoNodes = fbxTree.Objects.Video;

                for (var nodeID in videoNodes) {

                    var videoNode = videoNodes[nodeID];

                    var id = parseInt(nodeID);

                    images[id] = videoNode.RelativeFilename || videoNode.Filename;

                    // raw image data is in videoNode.Content
                    if ('Content' in videoNode) {

                        var arrayBufferContent = (videoNode.Content instanceof ArrayBuffer) && (videoNode.Content.byteLength > 0);
                        var base64Content = (typeof videoNode.Content === 'string') && (videoNode.Content !== '');

                        if (arrayBufferContent || base64Content) {

                            var image = this.parseImage(videoNodes[nodeID]);

                            blobs[videoNode.RelativeFilename || videoNode.Filename] = image;

                        }

                    }

                }

            }

            for (var id in images) {

                var filename = images[id];

                if (blobs[filename] !== undefined) images[id] = blobs[filename];
                else images[id] = images[id].split('\\').pop();

            }

            return images;

        },

        // Parse embedded image data in FBXTree.Video.Content
        parseImage: function (videoNode) {

            var content = videoNode.Content;
            var fileName = videoNode.RelativeFilename || videoNode.Filename;
            var extension = fileName.slice(fileName.lastIndexOf('.') + 1).toLowerCase();

            var type;

            switch (extension) {

                case 'bmp':

                    type = 'image/bmp';
                    break;

                case 'jpg':
                case 'jpeg':

                    type = 'image/jpeg';
                    break;

                case 'png':

                    type = 'image/png';
                    break;

                case 'tif':

                    type = 'image/tiff';
                    break;

                case 'tga':

                    if (typeof THREE.TGALoader !== 'function') {

                        console.warn('FBXLoader: THREE.TGALoader is required to load TGA textures');
                        return;

                    } else {

                        if (THREE.Loader.Handlers.get('.tga') === null) {

                            THREE.Loader.Handlers.add(/\.tga$/i, new THREE.TGALoader());

                        }

                        type = 'image/tga';
                        break;

                    }

                default:

                    console.warn('FBXLoader: Image type "' + extension + '" is not supported.');
                    return;

            }

            if (typeof content === 'string') { // ASCII format

                return 'data:' + type + ';base64,' + content;

            } else { // Binary Format

                var array = new Uint8Array(content);
                return window.URL.createObjectURL(new Blob([array], { type: type }));

            }

        },

        // Parse nodes in FBXTree.Objects.Texture
        // These contain details such as UV scaling, cropping, rotation etc and are connected
        // to images in FBXTree.Objects.Video
        parseTextures: function (images) {

            var textureMap = new Map();

            if ('Texture' in fbxTree.Objects) {

                var textureNodes = fbxTree.Objects.Texture;
                for (var nodeID in textureNodes) {

                    var texture = this.parseTexture(textureNodes[nodeID], images);
                    textureMap.set(parseInt(nodeID), texture);

                }

            }

            return textureMap;

        },

        // Parse individual node in FBXTree.Objects.Texture
        parseTexture: function (textureNode, images) {

            var texture = this.loadTexture(textureNode, images);

            texture.ID = textureNode.id;

            texture.name = textureNode.attrName;

            var wrapModeU = textureNode.WrapModeU;
            var wrapModeV = textureNode.WrapModeV;

            var valueU = wrapModeU !== undefined ? wrapModeU.value : 0;
            var valueV = wrapModeV !== undefined ? wrapModeV.value : 0;

            // http://download.autodesk.com/us/fbx/SDKdocs/FBX_SDK_Help/files/fbxsdkref/class_k_fbx_texture.html#889640e63e2e681259ea81061b85143a
            // 0: repeat(default), 1: clamp

            texture.wrapS = valueU === 0 ? THREE.RepeatWrapping : THREE.ClampToEdgeWrapping;
            texture.wrapT = valueV === 0 ? THREE.RepeatWrapping : THREE.ClampToEdgeWrapping;

            if ('Scaling' in textureNode) {

                var values = textureNode.Scaling.value;

                texture.repeat.x = values[0];
                texture.repeat.y = values[1];

            }

            return texture;

        },

        // load a texture specified as a blob or data URI, or via an external URL using THREE.TextureLoader
        loadTexture: function (textureNode, images) {

            var fileName;

            var currentPath = this.textureLoader.path;

            var children = connections.get(textureNode.id).children;

            if (children !== undefined && children.length > 0 && images[children[0].ID] !== undefined) {

                fileName = images[children[0].ID];

                if (fileName.indexOf('blob:') === 0 || fileName.indexOf('data:') === 0) {

                    this.textureLoader.setPath(undefined);

                }

            }

            var texture;

            var extension = textureNode.FileName.slice(-3).toLowerCase();

            if (extension === 'tga') {

                var loader = THREE.Loader.Handlers.get('.tga');

                if (loader === null) {

                    console.warn('FBXLoader: TGALoader not found, creating empty placeholder texture for', fileName);
                    texture = new THREE.Texture();

                } else {

                    texture = loader.load(fileName);

                }

            } else if (extension === 'psd') {

                console.warn('FBXLoader: PSD textures are not supported, creating empty placeholder texture for', fileName);
                texture = new THREE.Texture();

            } else {

                texture = this.textureLoader.load(fileName);

            }

            this.textureLoader.setPath(currentPath);

            return texture;

        },

        // Parse nodes in FBXTree.Objects.Material
        parseMaterials: function (textureMap) {

            var materialMap = new Map();

            if ('Material' in fbxTree.Objects) {

                var materialNodes = fbxTree.Objects.Material;

                for (var nodeID in materialNodes) {

                    var material = this.parseMaterial(materialNodes[nodeID], textureMap);

                    if (material !== null) materialMap.set(parseInt(nodeID), material);

                }

            }

            return materialMap;

        },

        // Parse single node in FBXTree.Objects.Material
        // Materials are connected to texture maps in FBXTree.Objects.Textures
        // FBX format currently only supports Lambert and Phong shading models
        parseMaterial: function (materialNode, textureMap) {

            var ID = materialNode.id;
            var name = materialNode.attrName;
            var type = materialNode.ShadingModel;

            // Case where FBX wraps shading model in property object.
            if (typeof type === 'object') {

                type = type.value;

            }

            // Ignore unused materials which don't have any connections.
            if (!connections.has(ID)) return null;

            var parameters = this.parseParameters(materialNode, textureMap, ID);

            var material;

            switch (type.toLowerCase()) {

                case 'phong':
                    material = new THREE.MeshPhongMaterial();
                    break;
                case 'lambert':
                    material = new THREE.MeshLambertMaterial();
                    break;
                default:
                    console.warn('THREE.FBXLoader: unknown material type "%s". Defaulting to MeshPhongMaterial.', type);
                    material = new THREE.MeshPhongMaterial({ color: 0x3300ff });
                    break;

            }

            material.setValues(parameters);
            material.name = name;

            return material;

        },

        // Parse FBX material and return parameters suitable for a three.js material
        // Also parse the texture map and return any textures associated with the material
        parseParameters: function (materialNode, textureMap, ID) {

            var parameters = {};

            if (materialNode.BumpFactor) {

                parameters.bumpScale = materialNode.BumpFactor.value;

            }
            if (materialNode.Diffuse) {

                parameters.color = new THREE.Color().fromArray(materialNode.Diffuse.value);

            } else if (materialNode.DiffuseColor && materialNode.DiffuseColor.type === 'Color') {

                // The blender exporter exports diffuse here instead of in materialNode.Diffuse
                parameters.color = new THREE.Color().fromArray(materialNode.DiffuseColor.value);

            }
            if (materialNode.DisplacementFactor) {

                parameters.displacementScale = materialNode.DisplacementFactor.value;

            }
            if (materialNode.Emissive) {

                parameters.emissive = new THREE.Color().fromArray(materialNode.Emissive.value);

            } else if (materialNode.EmissiveColor && materialNode.EmissiveColor.type === 'Color') {

                // The blender exporter exports emissive color here instead of in materialNode.Emissive
                parameters.emissive = new THREE.Color().fromArray(materialNode.EmissiveColor.value);

            }
            if (materialNode.EmissiveFactor) {

                parameters.emissiveIntensity = parseFloat(materialNode.EmissiveFactor.value);

            }
            if (materialNode.Opacity) {

                parameters.opacity = parseFloat(materialNode.Opacity.value);

            }
            if (parameters.opacity < 1.0) {

                parameters.transparent = true;

            }
            if (materialNode.ReflectionFactor) {

                parameters.reflectivity = materialNode.ReflectionFactor.value;

            }
            if (materialNode.Shininess) {

                parameters.shininess = materialNode.Shininess.value;

            }
            if (materialNode.Specular) {

                parameters.specular = new THREE.Color().fromArray(materialNode.Specular.value);

            } else if (materialNode.SpecularColor && materialNode.SpecularColor.type === 'Color') {

                // The blender exporter exports specular color here instead of in materialNode.Specular
                parameters.specular = new THREE.Color().fromArray(materialNode.SpecularColor.value);

            }

            var self = this;
            connections.get(ID).children.forEach(function (child) {

                var type = child.relationship;

                switch (type) {

                    case 'Bump':
                        parameters.bumpMap = self.getTexture(textureMap, child.ID);
                        break;

                    case 'DiffuseColor':
                        parameters.map = self.getTexture(textureMap, child.ID);
                        break;

                    case 'DisplacementColor':
                        parameters.displacementMap = self.getTexture(textureMap, child.ID);
                        break;


                    case 'EmissiveColor':
                        parameters.emissiveMap = self.getTexture(textureMap, child.ID);
                        break;

                    case 'NormalMap':
                        parameters.normalMap = self.getTexture(textureMap, child.ID);
                        break;

                    case 'ReflectionColor':
                        parameters.envMap = self.getTexture(textureMap, child.ID);
                        parameters.envMap.mapping = THREE.EquirectangularReflectionMapping;
                        break;

                    case 'SpecularColor':
                        parameters.specularMap = self.getTexture(textureMap, child.ID);
                        break;

                    case 'TransparentColor':
                        parameters.alphaMap = self.getTexture(textureMap, child.ID);
                        parameters.transparent = true;
                        break;

                    case 'AmbientColor':
                    case 'ShininessExponent': // AKA glossiness map
                    case 'SpecularFactor': // AKA specularLevel
                    case 'VectorDisplacementColor': // NOTE: Seems to be a copy of DisplacementColor
                    default:
                        console.warn('THREE.FBXLoader: %s map is not supported in three.js, skipping texture.', type);
                        break;

                }

            });

            return parameters;

        },

        // get a texture from the textureMap for use by a material.
        getTexture: function (textureMap, id) {

            // if the texture is a layered texture, just use the first layer and issue a warning
            if ('LayeredTexture' in fbxTree.Objects && id in fbxTree.Objects.LayeredTexture) {

                console.warn('THREE.FBXLoader: layered textures are not supported in three.js. Discarding all but first layer.');
                id = connections.get(id).children[0].ID;

            }

            return textureMap.get(id);

        },

        // Parse nodes in FBXTree.Objects.Deformer
        // Deformer node can contain skinning or Vertex Cache animation data, however only skinning is supported here
        // Generates map of Skeleton-like objects for use later when generating and binding skeletons.
        parseDeformers: function () {

            var skeletons = {};
            var morphTargets = {};

            if ('Deformer' in fbxTree.Objects) {

                var DeformerNodes = fbxTree.Objects.Deformer;

                for (var nodeID in DeformerNodes) {

                    var deformerNode = DeformerNodes[nodeID];

                    var relationships = connections.get(parseInt(nodeID));

                    if (deformerNode.attrType === 'Skin') {

                        var skeleton = this.parseSkeleton(relationships, DeformerNodes);
                        skeleton.ID = nodeID;

                        if (relationships.parents.length > 1) console.warn('THREE.FBXLoader: skeleton attached to more than one geometry is not supported.');
                        skeleton.geometryID = relationships.parents[0].ID;

                        skeletons[nodeID] = skeleton;

                    } else if (deformerNode.attrType === 'BlendShape') {

                        var morphTarget = {
                            id: nodeID,
                        };

                        morphTarget.rawTargets = this.parseMorphTargets(relationships, DeformerNodes);
                        morphTarget.id = nodeID;

                        if (relationships.parents.length > 1) console.warn('THREE.FBXLoader: morph target attached to more than one geometry is not supported.');

                        morphTargets[nodeID] = morphTarget;

                    }

                }

            }

            return {

                skeletons: skeletons,
                morphTargets: morphTargets,

            };

        },

        // Parse single nodes in FBXTree.Objects.Deformer
        // The top level skeleton node has type 'Skin' and sub nodes have type 'Cluster'
        // Each skin node represents a skeleton and each cluster node represents a bone
        parseSkeleton: function (relationships, deformerNodes) {

            var rawBones = [];

            relationships.children.forEach(function (child) {

                var boneNode = deformerNodes[child.ID];

                if (boneNode.attrType !== 'Cluster') return;

                var rawBone = {

                    ID: child.ID,
                    indices: [],
                    weights: [],
                    transform: new THREE.Matrix4().fromArray(boneNode.Transform.a),
                    transformLink: new THREE.Matrix4().fromArray(boneNode.TransformLink.a),
                    linkMode: boneNode.Mode,

                };

                if ('Indexes' in boneNode) {

                    rawBone.indices = boneNode.Indexes.a;
                    rawBone.weights = boneNode.Weights.a;

                }

                rawBones.push(rawBone);

            });

            return {

                rawBones: rawBones,
                bones: []

            };

        },

        // The top level morph deformer node has type "BlendShape" and sub nodes have type "BlendShapeChannel"
        parseMorphTargets: function (relationships, deformerNodes) {

            var rawMorphTargets = [];

            for (var i = 0; i < relationships.children.length; i++) {

                if (i === 8) {

                    console.warn('FBXLoader: maximum of 8 morph targets supported. Ignoring additional targets.');

                    break;

                }

                var child = relationships.children[i];

                var morphTargetNode = deformerNodes[child.ID];

                var rawMorphTarget = {

                    name: morphTargetNode.attrName,
                    initialWeight: morphTargetNode.DeformPercent,
                    id: morphTargetNode.id,
                    fullWeights: morphTargetNode.FullWeights.a

                };

                if (morphTargetNode.attrType !== 'BlendShapeChannel') return;

                var targetRelationships = connections.get(parseInt(child.ID));

                targetRelationships.children.forEach(function (child) {

                    if (child.relationship === undefined) rawMorphTarget.geoID = child.ID;

                });

                rawMorphTargets.push(rawMorphTarget);

            }

            return rawMorphTargets;

        },

        // create the main THREE.Group() to be returned by the loader
        parseScene: function (deformers, geometryMap, materialMap) {

            sceneGraph = new THREE.Group();

            var modelMap = this.parseModels(deformers.skeletons, geometryMap, materialMap);

            var modelNodes = fbxTree.Objects.Model;

            var self = this;
            modelMap.forEach(function (model) {

                var modelNode = modelNodes[model.ID];
                self.setLookAtProperties(model, modelNode);

                var parentConnections = connections.get(model.ID).parents;

                parentConnections.forEach(function (connection) {

                    var parent = modelMap.get(connection.ID);
                    if (parent !== undefined) parent.add(model);

                });

                if (model.parent === null) {

                    sceneGraph.add(model);

                }


            });

            this.bindSkeleton(deformers.skeletons, geometryMap, modelMap);

            this.createAmbientLight();

            this.setupMorphMaterials();

            var animations = new AnimationParser().parse();

            // if all the models where already combined in a single group, just return that
            if (sceneGraph.children.length === 1 && sceneGraph.children[0].isGroup) {

                sceneGraph.children[0].animations = animations;
                sceneGraph = sceneGraph.children[0];

            }

            sceneGraph.animations = animations;

        },

        // parse nodes in FBXTree.Objects.Model
        parseModels: function (skeletons, geometryMap, materialMap) {

            var modelMap = new Map();
            var modelNodes = fbxTree.Objects.Model;

            for (var nodeID in modelNodes) {

                var id = parseInt(nodeID);
                var node = modelNodes[nodeID];
                var relationships = connections.get(id);

                var model = this.buildSkeleton(relationships, skeletons, id, node.attrName);

                if (!model) {

                    switch (node.attrType) {

                        case 'Camera':
                            model = this.createCamera(relationships);
                            break;
                        case 'Light':
                            model = this.createLight(relationships);
                            break;
                        case 'Mesh':
                            model = this.createMesh(relationships, geometryMap, materialMap);
                            break;
                        case 'NurbsCurve':
                            model = this.createCurve(relationships, geometryMap);
                            break;
                        case 'LimbNode': // usually associated with a Bone, however if a Bone was not created we'll make a Group instead
                        case 'Null':
                        default:
                            model = new THREE.Group();
                            break;

                    }

                    model.name = THREE.PropertyBinding.sanitizeNodeName(node.attrName);
                    model.ID = id;

                }

                this.setModelTransforms(model, node);
                modelMap.set(id, model);

            }

            return modelMap;

        },

        buildSkeleton: function (relationships, skeletons, id, name) {

            var bone = null;

            relationships.parents.forEach(function (parent) {

                for (var ID in skeletons) {

                    var skeleton = skeletons[ID];

                    skeleton.rawBones.forEach(function (rawBone, i) {

                        if (rawBone.ID === parent.ID) {

                            var subBone = bone;
                            bone = new THREE.Bone();
                            bone.matrixWorld.copy(rawBone.transformLink);

                            // set name and id here - otherwise in cases where "subBone" is created it will not have a name / id
                            bone.name = THREE.PropertyBinding.sanitizeNodeName(name);
                            bone.ID = id;

                            skeleton.bones[i] = bone;

                            // In cases where a bone is shared between multiple meshes
                            // duplicate the bone here and and it as a child of the first bone
                            if (subBone !== null) {

                                bone.add(subBone);

                            }

                        }

                    });

                }

            });

            return bone;

        },

        // create a THREE.PerspectiveCamera or THREE.OrthographicCamera
        createCamera: function (relationships) {

            var model;
            var cameraAttribute;

            relationships.children.forEach(function (child) {

                var attr = fbxTree.Objects.NodeAttribute[child.ID];

                if (attr !== undefined) {

                    cameraAttribute = attr;

                }

            });

            if (cameraAttribute === undefined) {

                model = new THREE.Object3D();

            } else {

                var type = 0;
                if (cameraAttribute.CameraProjectionType !== undefined && cameraAttribute.CameraProjectionType.value === 1) {

                    type = 1;

                }

                var nearClippingPlane = 1;
                if (cameraAttribute.NearPlane !== undefined) {

                    nearClippingPlane = cameraAttribute.NearPlane.value / 1000;

                }

                var farClippingPlane = 1000;
                if (cameraAttribute.FarPlane !== undefined) {

                    farClippingPlane = cameraAttribute.FarPlane.value / 1000;

                }


                var width = window.innerWidth;
                var height = window.innerHeight;

                if (cameraAttribute.AspectWidth !== undefined && cameraAttribute.AspectHeight !== undefined) {

                    width = cameraAttribute.AspectWidth.value;
                    height = cameraAttribute.AspectHeight.value;

                }

                var aspect = width / height;

                var fov = 45;
                if (cameraAttribute.FieldOfView !== undefined) {

                    fov = cameraAttribute.FieldOfView.value;

                }

                var focalLength = cameraAttribute.FocalLength ? cameraAttribute.FocalLength.value : null;

                switch (type) {

                    case 0: // Perspective
                        model = new THREE.PerspectiveCamera(fov, aspect, nearClippingPlane, farClippingPlane);
                        if (focalLength !== null) model.setFocalLength(focalLength);
                        break;

                    case 1: // Orthographic
                        model = new THREE.OrthographicCamera(-width / 2, width / 2, height / 2, -height / 2, nearClippingPlane, farClippingPlane);
                        break;

                    default:
                        console.warn('THREE.FBXLoader: Unknown camera type ' + type + '.');
                        model = new THREE.Object3D();
                        break;

                }

            }

            return model;

        },

        // Create a THREE.DirectionalLight, THREE.PointLight or THREE.SpotLight
        createLight: function (relationships) {

            var model;
            var lightAttribute;

            relationships.children.forEach(function (child) {

                var attr = fbxTree.Objects.NodeAttribute[child.ID];

                if (attr !== undefined) {

                    lightAttribute = attr;

                }

            });

            if (lightAttribute === undefined) {

                model = new THREE.Object3D();

            } else {

                var type;

                // LightType can be undefined for Point lights
                if (lightAttribute.LightType === undefined) {

                    type = 0;

                } else {

                    type = lightAttribute.LightType.value;

                }

                var color = 0xffffff;

                if (lightAttribute.Color !== undefined) {

                    color = new THREE.Color().fromArray(lightAttribute.Color.value);

                }

                var intensity = (lightAttribute.Intensity === undefined) ? 1 : lightAttribute.Intensity.value / 100;

                // light disabled
                if (lightAttribute.CastLightOnObject !== undefined && lightAttribute.CastLightOnObject.value === 0) {

                    intensity = 0;

                }

                var distance = 0;
                if (lightAttribute.FarAttenuationEnd !== undefined) {

                    if (lightAttribute.EnableFarAttenuation !== undefined && lightAttribute.EnableFarAttenuation.value === 0) {

                        distance = 0;

                    } else {

                        distance = lightAttribute.FarAttenuationEnd.value;

                    }

                }

                // TODO: could this be calculated linearly from FarAttenuationStart to FarAttenuationEnd?
                var decay = 1;

                switch (type) {

                    case 0: // Point
                        model = new THREE.PointLight(color, intensity, distance, decay);
                        break;

                    case 1: // Directional
                        model = new THREE.DirectionalLight(color, intensity);
                        break;

                    case 2: // Spot
                        var angle = Math.PI / 3;

                        if (lightAttribute.InnerAngle !== undefined) {

                            angle = THREE.Math.degToRad(lightAttribute.InnerAngle.value);

                        }

                        var penumbra = 0;
                        if (lightAttribute.OuterAngle !== undefined) {

                            // TODO: this is not correct - FBX calculates outer and inner angle in degrees
                            // with OuterAngle > InnerAngle && OuterAngle <= Math.PI
                            // while three.js uses a penumbra between (0, 1) to attenuate the inner angle
                            penumbra = THREE.Math.degToRad(lightAttribute.OuterAngle.value);
                            penumbra = Math.max(penumbra, 1);

                        }

                        model = new THREE.SpotLight(color, intensity, distance, angle, penumbra, decay);
                        break;

                    default:
                        console.warn('THREE.FBXLoader: Unknown light type ' + lightAttribute.LightType.value + ', defaulting to a THREE.PointLight.');
                        model = new THREE.PointLight(color, intensity);
                        break;

                }

                if (lightAttribute.CastShadows !== undefined && lightAttribute.CastShadows.value === 1) {

                    model.castShadow = true;

                }

            }

            return model;

        },

        createMesh: function (relationships, geometryMap, materialMap) {

            var model;
            var geometry = null;
            var material = null;
            var materials = [];

            // get geometry and materials(s) from connections
            relationships.children.forEach(function (child) {

                if (geometryMap.has(child.ID)) {

                    geometry = geometryMap.get(child.ID);

                }

                if (materialMap.has(child.ID)) {

                    materials.push(materialMap.get(child.ID));

                }

            });

            if (materials.length > 1) {

                material = materials;

            } else if (materials.length > 0) {

                material = materials[0];

            } else {

                material = new THREE.MeshPhongMaterial({ color: 0xcccccc });
                materials.push(material);

            }

            if ('color' in geometry.attributes) {

                materials.forEach(function (material) {

                    material.vertexColors = THREE.VertexColors;

                });

            }

            if (geometry.FBX_Deformer) {

                materials.forEach(function (material) {

                    material.skinning = true;

                });

                model = new THREE.SkinnedMesh(geometry, material);

            } else {

                model = new THREE.Mesh(geometry, material);

            }

            return model;

        },

        createCurve: function (relationships, geometryMap) {

            var geometry = relationships.children.reduce(function (geo, child) {

                if (geometryMap.has(child.ID)) geo = geometryMap.get(child.ID);

                return geo;

            }, null);

            // FBX does not list materials for Nurbs lines, so we'll just put our own in here.
            var material = new THREE.LineBasicMaterial({ color: 0x3300ff, linewidth: 1 });
            return new THREE.Line(geometry, material);

        },

        // parse the model node for transform details and apply them to the model
        setModelTransforms: function (model, modelNode) {

            var transformData = {};

            if ('RotationOrder' in modelNode) transformData.eulerOrder = parseInt(modelNode.RotationOrder.value);
            if ('Lcl_Translation' in modelNode) transformData.translation = modelNode.Lcl_Translation.value;
            if ('RotationOffset' in modelNode) transformData.rotationOffset = modelNode.RotationOffset.value;
            if ('Lcl_Rotation' in modelNode) transformData.rotation = modelNode.Lcl_Rotation.value;
            if ('PreRotation' in modelNode) transformData.preRotation = modelNode.PreRotation.value;
            if ('PostRotation' in modelNode) transformData.postRotation = modelNode.PostRotation.value;
            if ('Lcl_Scaling' in modelNode) transformData.scale = modelNode.Lcl_Scaling.value;

            var transform = generateTransform(transformData);

            model.applyMatrix(transform);

        },

        setLookAtProperties: function (model, modelNode) {

            if ('LookAtProperty' in modelNode) {

                var children = connections.get(model.ID).children;

                children.forEach(function (child) {

                    if (child.relationship === 'LookAtProperty') {

                        var lookAtTarget = fbxTree.Objects.Model[child.ID];

                        if ('Lcl_Translation' in lookAtTarget) {

                            var pos = lookAtTarget.Lcl_Translation.value;

                            // DirectionalLight, SpotLight
                            if (model.target !== undefined) {

                                model.target.position.fromArray(pos);
                                sceneGraph.add(model.target);

                            } else { // Cameras and other Object3Ds

                                model.lookAt(new THREE.Vector3().fromArray(pos));

                            }

                        }

                    }

                });

            }

        },

        bindSkeleton: function (skeletons, geometryMap, modelMap) {

            var bindMatrices = this.parsePoseNodes();

            for (var ID in skeletons) {

                var skeleton = skeletons[ID];

                var parents = connections.get(parseInt(skeleton.ID)).parents;

                parents.forEach(function (parent) {

                    if (geometryMap.has(parent.ID)) {

                        var geoID = parent.ID;
                        var geoRelationships = connections.get(geoID);

                        geoRelationships.parents.forEach(function (geoConnParent) {

                            if (modelMap.has(geoConnParent.ID)) {

                                var model = modelMap.get(geoConnParent.ID);

                                model.bind(new THREE.Skeleton(skeleton.bones), bindMatrices[geoConnParent.ID]);

                            }

                        });

                    }

                });

            }

        },

        parsePoseNodes: function () {

            var bindMatrices = {};

            if ('Pose' in fbxTree.Objects) {

                var BindPoseNode = fbxTree.Objects.Pose;

                for (var nodeID in BindPoseNode) {

                    if (BindPoseNode[nodeID].attrType === 'BindPose') {

                        var poseNodes = BindPoseNode[nodeID].PoseNode;

                        if (Array.isArray(poseNodes)) {

                            poseNodes.forEach(function (poseNode) {

                                bindMatrices[poseNode.Node] = new THREE.Matrix4().fromArray(poseNode.Matrix.a);

                            });

                        } else {

                            bindMatrices[poseNodes.Node] = new THREE.Matrix4().fromArray(poseNodes.Matrix.a);

                        }

                    }

                }

            }

            return bindMatrices;

        },

        // Parse ambient color in FBXTree.GlobalSettings - if it's not set to black (default), create an ambient light
        createAmbientLight: function () {

            if ('GlobalSettings' in fbxTree && 'AmbientColor' in fbxTree.GlobalSettings) {

                var ambientColor = fbxTree.GlobalSettings.AmbientColor.value;
                var r = ambientColor[0];
                var g = ambientColor[1];
                var b = ambientColor[2];

                if (r !== 0 || g !== 0 || b !== 0) {

                    var color = new THREE.Color(r, g, b);
                    sceneGraph.add(new THREE.AmbientLight(color, 1));

                }

            }

        },

        setupMorphMaterials: function () {

            sceneGraph.traverse(function (child) {

                if (child.isMesh) {

                    if (child.geometry.morphAttributes.position || child.geometry.morphAttributes.normal) {

                        var uuid = child.uuid;
                        var matUuid = child.material.uuid;

                        // if a geometry has morph targets, it cannot share the material with other geometries
                        var sharedMat = false;

                        sceneGraph.traverse(function (child) {

                            if (child.isMesh) {

                                if (child.material.uuid === matUuid && child.uuid !== uuid) sharedMat = true;

                            }

                        });

                        if (sharedMat === true) child.material = child.material.clone();

                        child.material.morphTargets = true;

                    }

                }

            });

        },

    };

    // parse Geometry data from FBXTree and return map of BufferGeometries
    function GeometryParser() { }

    GeometryParser.prototype = {

        constructor: GeometryParser,

        // Parse nodes in FBXTree.Objects.Geometry
        parse: function (deformers) {

            var geometryMap = new Map();

            if ('Geometry' in fbxTree.Objects) {

                var geoNodes = fbxTree.Objects.Geometry;

                for (var nodeID in geoNodes) {

                    var relationships = connections.get(parseInt(nodeID));
                    var geo = this.parseGeometry(relationships, geoNodes[nodeID], deformers);

                    geometryMap.set(parseInt(nodeID), geo);

                }

            }

            return geometryMap;

        },

        // Parse single node in FBXTree.Objects.Geometry
        parseGeometry: function (relationships, geoNode, deformers) {

            switch (geoNode.attrType) {

                case 'Mesh':
                    return this.parseMeshGeometry(relationships, geoNode, deformers);
                    break;

                case 'NurbsCurve':
                    return this.parseNurbsGeometry(geoNode);
                    break;

            }

        },

        // Parse single node mesh geometry in FBXTree.Objects.Geometry
        parseMeshGeometry: function (relationships, geoNode, deformers) {

            var skeletons = deformers.skeletons;
            var morphTargets = deformers.morphTargets;

            var modelNodes = relationships.parents.map(function (parent) {

                return fbxTree.Objects.Model[parent.ID];

            });

            // don't create geometry if it is not associated with any models
            if (modelNodes.length === 0) return;

            var skeleton = relationships.children.reduce(function (skeleton, child) {

                if (skeletons[child.ID] !== undefined) skeleton = skeletons[child.ID];

                return skeleton;

            }, null);

            var morphTarget = relationships.children.reduce(function (morphTarget, child) {

                if (morphTargets[child.ID] !== undefined) morphTarget = morphTargets[child.ID];

                return morphTarget;

            }, null);

            // TODO: if there is more than one model associated with the geometry, AND the models have
            // different geometric transforms, then this will cause problems
            // if ( modelNodes.length > 1 ) { }

            // For now just assume one model and get the preRotations from that
            var modelNode = modelNodes[0];

            var transformData = {};

            if ('RotationOrder' in modelNode) transformData.eulerOrder = modelNode.RotationOrder.value;
            if ('GeometricTranslation' in modelNode) transformData.translation = modelNode.GeometricTranslation.value;
            if ('GeometricRotation' in modelNode) transformData.rotation = modelNode.GeometricRotation.value;
            if ('GeometricScaling' in modelNode) transformData.scale = modelNode.GeometricScaling.value;

            var transform = generateTransform(transformData);

            return this.genGeometry(geoNode, skeleton, morphTarget, transform);

        },

        // Generate a THREE.BufferGeometry from a node in FBXTree.Objects.Geometry
        genGeometry: function (geoNode, skeleton, morphTarget, preTransform) {

            var geo = new THREE.BufferGeometry();
            if (geoNode.attrName) geo.name = geoNode.attrName;

            var geoInfo = this.parseGeoNode(geoNode, skeleton);
            var buffers = this.genBuffers(geoInfo);

            var positionAttribute = new THREE.Float32BufferAttribute(buffers.vertex, 3);

            preTransform.applyToBufferAttribute(positionAttribute);

            geo.addAttribute('position', positionAttribute);

            if (buffers.colors.length > 0) {

                geo.addAttribute('color', new THREE.Float32BufferAttribute(buffers.colors, 3));

            }

            if (skeleton) {

                geo.addAttribute('skinIndex', new THREE.Uint16BufferAttribute(buffers.weightsIndices, 4));

                geo.addAttribute('skinWeight', new THREE.Float32BufferAttribute(buffers.vertexWeights, 4));

                // used later to bind the skeleton to the model
                geo.FBX_Deformer = skeleton;

            }

            if (buffers.normal.length > 0) {

                var normalAttribute = new THREE.Float32BufferAttribute(buffers.normal, 3);

                var normalMatrix = new THREE.Matrix3().getNormalMatrix(preTransform);
                normalMatrix.applyToBufferAttribute(normalAttribute);

                geo.addAttribute('normal', normalAttribute);

            }

            buffers.uvs.forEach(function (uvBuffer, i) {

                // subsequent uv buffers are called 'uv1', 'uv2', ...
                var name = 'uv' + (i + 1).toString();

                // the first uv buffer is just called 'uv'
                if (i === 0) {

                    name = 'uv';

                }

                geo.addAttribute(name, new THREE.Float32BufferAttribute(buffers.uvs[i], 2));

            });

            if (geoInfo.material && geoInfo.material.mappingType !== 'AllSame') {

                // Convert the material indices of each vertex into rendering groups on the geometry.
                var prevMaterialIndex = buffers.materialIndex[0];
                var startIndex = 0;

                buffers.materialIndex.forEach(function (currentIndex, i) {

                    if (currentIndex !== prevMaterialIndex) {

                        geo.addGroup(startIndex, i - startIndex, prevMaterialIndex);

                        prevMaterialIndex = currentIndex;
                        startIndex = i;

                    }

                });

                // the loop above doesn't add the last group, do that here.
                if (geo.groups.length > 0) {

                    var lastGroup = geo.groups[geo.groups.length - 1];
                    var lastIndex = lastGroup.start + lastGroup.count;

                    if (lastIndex !== buffers.materialIndex.length) {

                        geo.addGroup(lastIndex, buffers.materialIndex.length - lastIndex, prevMaterialIndex);

                    }

                }

                // case where there are multiple materials but the whole geometry is only
                // using one of them
                if (geo.groups.length === 0) {

                    geo.addGroup(0, buffers.materialIndex.length, buffers.materialIndex[0]);

                }

            }

            this.addMorphTargets(geo, geoNode, morphTarget, preTransform);

            return geo;

        },

        parseGeoNode: function (geoNode, skeleton) {

            var geoInfo = {};

            geoInfo.vertexPositions = (geoNode.Vertices !== undefined) ? geoNode.Vertices.a : [];
            geoInfo.vertexIndices = (geoNode.PolygonVertexIndex !== undefined) ? geoNode.PolygonVertexIndex.a : [];

            if (geoNode.LayerElementColor) {

                geoInfo.color = this.parseVertexColors(geoNode.LayerElementColor[0]);

            }

            if (geoNode.LayerElementMaterial) {

                geoInfo.material = this.parseMaterialIndices(geoNode.LayerElementMaterial[0]);

            }

            if (geoNode.LayerElementNormal) {

                geoInfo.normal = this.parseNormals(geoNode.LayerElementNormal[0]);

            }

            if (geoNode.LayerElementUV) {

                geoInfo.uv = [];

                var i = 0;
                while (geoNode.LayerElementUV[i]) {

                    geoInfo.uv.push(this.parseUVs(geoNode.LayerElementUV[i]));
                    i++;

                }

            }

            geoInfo.weightTable = {};

            if (skeleton !== null) {

                geoInfo.skeleton = skeleton;

                skeleton.rawBones.forEach(function (rawBone, i) {

                    // loop over the bone's vertex indices and weights
                    rawBone.indices.forEach(function (index, j) {

                        if (geoInfo.weightTable[index] === undefined) geoInfo.weightTable[index] = [];

                        geoInfo.weightTable[index].push({

                            id: i,
                            weight: rawBone.weights[j],

                        });

                    });

                });

            }

            return geoInfo;

        },

        genBuffers: function (geoInfo) {

            var buffers = {
                vertex: [],
                normal: [],
                colors: [],
                uvs: [],
                materialIndex: [],
                vertexWeights: [],
                weightsIndices: [],
            };

            var polygonIndex = 0;
            var faceLength = 0;
            var displayedWeightsWarning = false;

            // these will hold data for a single face
            var facePositionIndexes = [];
            var faceNormals = [];
            var faceColors = [];
            var faceUVs = [];
            var faceWeights = [];
            var faceWeightIndices = [];

            var self = this;
            geoInfo.vertexIndices.forEach(function (vertexIndex, polygonVertexIndex) {

                var endOfFace = false;

                // Face index and vertex index arrays are combined in a single array
                // A cube with quad faces looks like this:
                // PolygonVertexIndex: *24 {
                //  a: 0, 1, 3, -3, 2, 3, 5, -5, 4, 5, 7, -7, 6, 7, 1, -1, 1, 7, 5, -4, 6, 0, 2, -5
                //  }
                // Negative numbers mark the end of a face - first face here is 0, 1, 3, -3
                // to find index of last vertex bit shift the index: ^ - 1
                if (vertexIndex < 0) {

                    vertexIndex = vertexIndex ^ -1; // equivalent to ( x * -1 ) - 1
                    endOfFace = true;

                }

                var weightIndices = [];
                var weights = [];

                facePositionIndexes.push(vertexIndex * 3, vertexIndex * 3 + 1, vertexIndex * 3 + 2);

                if (geoInfo.color) {

                    var data = getData(polygonVertexIndex, polygonIndex, vertexIndex, geoInfo.color);

                    faceColors.push(data[0], data[1], data[2]);

                }

                if (geoInfo.skeleton) {

                    if (geoInfo.weightTable[vertexIndex] !== undefined) {

                        geoInfo.weightTable[vertexIndex].forEach(function (wt) {

                            weights.push(wt.weight);
                            weightIndices.push(wt.id);

                        });


                    }

                    if (weights.length > 4) {

                        if (!displayedWeightsWarning) {

                            console.warn('THREE.FBXLoader: Vertex has more than 4 skinning weights assigned to vertex. Deleting additional weights.');
                            displayedWeightsWarning = true;

                        }

                        var wIndex = [0, 0, 0, 0];
                        var Weight = [0, 0, 0, 0];

                        weights.forEach(function (weight, weightIndex) {

                            var currentWeight = weight;
                            var currentIndex = weightIndices[weightIndex];

                            Weight.forEach(function (comparedWeight, comparedWeightIndex, comparedWeightArray) {

                                if (currentWeight > comparedWeight) {

                                    comparedWeightArray[comparedWeightIndex] = currentWeight;
                                    currentWeight = comparedWeight;

                                    var tmp = wIndex[comparedWeightIndex];
                                    wIndex[comparedWeightIndex] = currentIndex;
                                    currentIndex = tmp;

                                }

                            });

                        });

                        weightIndices = wIndex;
                        weights = Weight;

                    }

                    // if the weight array is shorter than 4 pad with 0s
                    while (weights.length < 4) {

                        weights.push(0);
                        weightIndices.push(0);

                    }

                    for (var i = 0; i < 4; ++i) {

                        faceWeights.push(weights[i]);
                        faceWeightIndices.push(weightIndices[i]);

                    }

                }

                if (geoInfo.normal) {

                    var data = getData(polygonVertexIndex, polygonIndex, vertexIndex, geoInfo.normal);

                    faceNormals.push(data[0], data[1], data[2]);

                }

                if (geoInfo.material && geoInfo.material.mappingType !== 'AllSame') {

                    var materialIndex = getData(polygonVertexIndex, polygonIndex, vertexIndex, geoInfo.material)[0];

                }

                if (geoInfo.uv) {

                    geoInfo.uv.forEach(function (uv, i) {

                        var data = getData(polygonVertexIndex, polygonIndex, vertexIndex, uv);

                        if (faceUVs[i] === undefined) {

                            faceUVs[i] = [];

                        }

                        faceUVs[i].push(data[0]);
                        faceUVs[i].push(data[1]);

                    });

                }

                faceLength++;

                if (endOfFace) {

                    self.genFace(buffers, geoInfo, facePositionIndexes, materialIndex, faceNormals, faceColors, faceUVs, faceWeights, faceWeightIndices, faceLength);

                    polygonIndex++;
                    faceLength = 0;

                    // reset arrays for the next face
                    facePositionIndexes = [];
                    faceNormals = [];
                    faceColors = [];
                    faceUVs = [];
                    faceWeights = [];
                    faceWeightIndices = [];

                }

            });

            return buffers;

        },

        // Generate data for a single face in a geometry. If the face is a quad then split it into 2 tris
        genFace: function (buffers, geoInfo, facePositionIndexes, materialIndex, faceNormals, faceColors, faceUVs, faceWeights, faceWeightIndices, faceLength) {

            for (var i = 2; i < faceLength; i++) {

                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[0]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[1]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[2]]);

                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3 + 1]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[(i - 1) * 3 + 2]]);

                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[i * 3]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[i * 3 + 1]]);
                buffers.vertex.push(geoInfo.vertexPositions[facePositionIndexes[i * 3 + 2]]);

                if (geoInfo.skeleton) {

                    buffers.vertexWeights.push(faceWeights[0]);
                    buffers.vertexWeights.push(faceWeights[1]);
                    buffers.vertexWeights.push(faceWeights[2]);
                    buffers.vertexWeights.push(faceWeights[3]);

                    buffers.vertexWeights.push(faceWeights[(i - 1) * 4]);
                    buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 1]);
                    buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 2]);
                    buffers.vertexWeights.push(faceWeights[(i - 1) * 4 + 3]);

                    buffers.vertexWeights.push(faceWeights[i * 4]);
                    buffers.vertexWeights.push(faceWeights[i * 4 + 1]);
                    buffers.vertexWeights.push(faceWeights[i * 4 + 2]);
                    buffers.vertexWeights.push(faceWeights[i * 4 + 3]);

                    buffers.weightsIndices.push(faceWeightIndices[0]);
                    buffers.weightsIndices.push(faceWeightIndices[1]);
                    buffers.weightsIndices.push(faceWeightIndices[2]);
                    buffers.weightsIndices.push(faceWeightIndices[3]);

                    buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4]);
                    buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 1]);
                    buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 2]);
                    buffers.weightsIndices.push(faceWeightIndices[(i - 1) * 4 + 3]);

                    buffers.weightsIndices.push(faceWeightIndices[i * 4]);
                    buffers.weightsIndices.push(faceWeightIndices[i * 4 + 1]);
                    buffers.weightsIndices.push(faceWeightIndices[i * 4 + 2]);
                    buffers.weightsIndices.push(faceWeightIndices[i * 4 + 3]);

                }

                if (geoInfo.color) {

                    buffers.colors.push(faceColors[0]);
                    buffers.colors.push(faceColors[1]);
                    buffers.colors.push(faceColors[2]);

                    buffers.colors.push(faceColors[(i - 1) * 3]);
                    buffers.colors.push(faceColors[(i - 1) * 3 + 1]);
                    buffers.colors.push(faceColors[(i - 1) * 3 + 2]);

                    buffers.colors.push(faceColors[i * 3]);
                    buffers.colors.push(faceColors[i * 3 + 1]);
                    buffers.colors.push(faceColors[i * 3 + 2]);

                }

                if (geoInfo.material && geoInfo.material.mappingType !== 'AllSame') {

                    buffers.materialIndex.push(materialIndex);
                    buffers.materialIndex.push(materialIndex);
                    buffers.materialIndex.push(materialIndex);

                }

                if (geoInfo.normal) {

                    buffers.normal.push(faceNormals[0]);
                    buffers.normal.push(faceNormals[1]);
                    buffers.normal.push(faceNormals[2]);

                    buffers.normal.push(faceNormals[(i - 1) * 3]);
                    buffers.normal.push(faceNormals[(i - 1) * 3 + 1]);
                    buffers.normal.push(faceNormals[(i - 1) * 3 + 2]);

                    buffers.normal.push(faceNormals[i * 3]);
                    buffers.normal.push(faceNormals[i * 3 + 1]);
                    buffers.normal.push(faceNormals[i * 3 + 2]);

                }

                if (geoInfo.uv) {

                    geoInfo.uv.forEach(function (uv, j) {

                        if (buffers.uvs[j] === undefined) buffers.uvs[j] = [];

                        buffers.uvs[j].push(faceUVs[j][0]);
                        buffers.uvs[j].push(faceUVs[j][1]);

                        buffers.uvs[j].push(faceUVs[j][(i - 1) * 2]);
                        buffers.uvs[j].push(faceUVs[j][(i - 1) * 2 + 1]);

                        buffers.uvs[j].push(faceUVs[j][i * 2]);
                        buffers.uvs[j].push(faceUVs[j][i * 2 + 1]);

                    });

                }

            }

        },

        addMorphTargets: function (parentGeo, parentGeoNode, morphTarget, preTransform) {

            if (morphTarget === null) return;

            parentGeo.morphAttributes.position = [];
            parentGeo.morphAttributes.normal = [];

            var self = this;
            morphTarget.rawTargets.forEach(function (rawTarget) {

                var morphGeoNode = fbxTree.Objects.Geometry[rawTarget.geoID];

                if (morphGeoNode !== undefined) {

                    self.genMorphGeometry(parentGeo, parentGeoNode, morphGeoNode, preTransform);

                }

            });

        },

        // a morph geometry node is similar to a standard  node, and the node is also contained
        // in FBXTree.Objects.Geometry, however it can only have attributes for position, normal
        // and a special attribute Index defining which vertices of the original geometry are affected
        // Normal and position attributes only have data for the vertices that are affected by the morph
        genMorphGeometry: function (parentGeo, parentGeoNode, morphGeoNode, preTransform) {

            var morphGeo = new THREE.BufferGeometry();
            if (morphGeoNode.attrName) morphGeo.name = morphGeoNode.attrName;

            var vertexIndices = (parentGeoNode.PolygonVertexIndex !== undefined) ? parentGeoNode.PolygonVertexIndex.a : [];

            // make a copy of the parent's vertex positions
            var vertexPositions = (parentGeoNode.Vertices !== undefined) ? parentGeoNode.Vertices.a.slice() : [];

            var morphPositions = (morphGeoNode.Vertices !== undefined) ? morphGeoNode.Vertices.a : [];
            var indices = (morphGeoNode.Indexes !== undefined) ? morphGeoNode.Indexes.a : [];

            for (var i = 0; i < indices.length; i++) {

                var morphIndex = indices[i] * 3;

                // FBX format uses blend shapes rather than morph targets. This can be converted
                // by additively combining the blend shape positions with the original geometry's positions
                vertexPositions[morphIndex] += morphPositions[i * 3];
                vertexPositions[morphIndex + 1] += morphPositions[i * 3 + 1];
                vertexPositions[morphIndex + 2] += morphPositions[i * 3 + 2];

            }

            // TODO: add morph normal support
            var morphGeoInfo = {
                vertexIndices: vertexIndices,
                vertexPositions: vertexPositions,
            };

            var morphBuffers = this.genBuffers(morphGeoInfo);

            var positionAttribute = new THREE.Float32BufferAttribute(morphBuffers.vertex, 3);
            positionAttribute.name = morphGeoNode.attrName;

            preTransform.applyToBufferAttribute(positionAttribute);

            parentGeo.morphAttributes.position.push(positionAttribute);

        },

        // Parse normal from FBXTree.Objects.Geometry.LayerElementNormal if it exists
        parseNormals: function (NormalNode) {

            var mappingType = NormalNode.MappingInformationType;
            var referenceType = NormalNode.ReferenceInformationType;
            var buffer = NormalNode.Normals.a;
            var indexBuffer = [];
            if (referenceType === 'IndexToDirect') {

                if ('NormalIndex' in NormalNode) {

                    indexBuffer = NormalNode.NormalIndex.a;

                } else if ('NormalsIndex' in NormalNode) {

                    indexBuffer = NormalNode.NormalsIndex.a;

                }

            }

            return {
                dataSize: 3,
                buffer: buffer,
                indices: indexBuffer,
                mappingType: mappingType,
                referenceType: referenceType
            };

        },

        // Parse UVs from FBXTree.Objects.Geometry.LayerElementUV if it exists
        parseUVs: function (UVNode) {

            var mappingType = UVNode.MappingInformationType;
            var referenceType = UVNode.ReferenceInformationType;
            var buffer = UVNode.UV.a;
            var indexBuffer = [];
            if (referenceType === 'IndexToDirect') {

                indexBuffer = UVNode.UVIndex.a;

            }

            return {
                dataSize: 2,
                buffer: buffer,
                indices: indexBuffer,
                mappingType: mappingType,
                referenceType: referenceType
            };

        },

        // Parse Vertex Colors from FBXTree.Objects.Geometry.LayerElementColor if it exists
        parseVertexColors: function (ColorNode) {

            var mappingType = ColorNode.MappingInformationType;
            var referenceType = ColorNode.ReferenceInformationType;
            var buffer = ColorNode.Colors.a;
            var indexBuffer = [];
            if (referenceType === 'IndexToDirect') {

                indexBuffer = ColorNode.ColorIndex.a;

            }

            return {
                dataSize: 4,
                buffer: buffer,
                indices: indexBuffer,
                mappingType: mappingType,
                referenceType: referenceType
            };

        },

        // Parse mapping and material data in FBXTree.Objects.Geometry.LayerElementMaterial if it exists
        parseMaterialIndices: function (MaterialNode) {

            var mappingType = MaterialNode.MappingInformationType;
            var referenceType = MaterialNode.ReferenceInformationType;

            if (mappingType === 'NoMappingInformation') {

                return {
                    dataSize: 1,
                    buffer: [0],
                    indices: [0],
                    mappingType: 'AllSame',
                    referenceType: referenceType
                };

            }

            var materialIndexBuffer = MaterialNode.Materials.a;

            // Since materials are stored as indices, there's a bit of a mismatch between FBX and what
            // we expect.So we create an intermediate buffer that points to the index in the buffer,
            // for conforming with the other functions we've written for other data.
            var materialIndices = [];

            for (var i = 0; i < materialIndexBuffer.length; ++i) {

                materialIndices.push(i);

            }

            return {
                dataSize: 1,
                buffer: materialIndexBuffer,
                indices: materialIndices,
                mappingType: mappingType,
                referenceType: referenceType
            };

        },

        // Generate a NurbGeometry from a node in FBXTree.Objects.Geometry
        parseNurbsGeometry: function (geoNode) {

            if (THREE.NURBSCurve === undefined) {

                console.error('THREE.FBXLoader: The loader relies on THREE.NURBSCurve for any nurbs present in the model. Nurbs will show up as empty geometry.');
                return new THREE.BufferGeometry();

            }

            var order = parseInt(geoNode.Order);

            if (isNaN(order)) {

                console.error('THREE.FBXLoader: Invalid Order %s given for geometry ID: %s', geoNode.Order, geoNode.id);
                return new THREE.BufferGeometry();

            }

            var degree = order - 1;

            var knots = geoNode.KnotVector.a;
            var controlPoints = [];
            var pointsValues = geoNode.Points.a;

            for (var i = 0, l = pointsValues.length; i < l; i += 4) {

                controlPoints.push(new THREE.Vector4().fromArray(pointsValues, i));

            }

            var startKnot, endKnot;

            if (geoNode.Form === 'Closed') {

                controlPoints.push(controlPoints[0]);

            } else if (geoNode.Form === 'Periodic') {

                startKnot = degree;
                endKnot = knots.length - 1 - startKnot;

                for (var i = 0; i < degree; ++i) {

                    controlPoints.push(controlPoints[i]);

                }

            }

            var curve = new THREE.NURBSCurve(degree, knots, controlPoints, startKnot, endKnot);
            var vertices = curve.getPoints(controlPoints.length * 7);

            var positions = new Float32Array(vertices.length * 3);

            vertices.forEach(function (vertex, i) {

                vertex.toArray(positions, i * 3);

            });

            var geometry = new THREE.BufferGeometry();
            geometry.addAttribute('position', new THREE.BufferAttribute(positions, 3));

            return geometry;

        },

    };

    // parse animation data from FBXTree
    function AnimationParser() { }

    AnimationParser.prototype = {

        constructor: AnimationParser,

        // take raw animation clips and turn them into three.js animation clips
        parse: function () {

            var animationClips = [];


            var rawClips = this.parseClips();

            if (rawClips === undefined) return;

            for (var key in rawClips) {

                var rawClip = rawClips[key];

                var clip = this.addClip(rawClip);

                animationClips.push(clip);

            }

            return animationClips;

        },

        parseClips: function () {

            // since the actual transformation data is stored in FBXTree.Objects.AnimationCurve,
            // if this is undefined we can safely assume there are no animations
            if (fbxTree.Objects.AnimationCurve === undefined) return undefined;

            var curveNodesMap = this.parseAnimationCurveNodes();

            this.parseAnimationCurves(curveNodesMap);

            var layersMap = this.parseAnimationLayers(curveNodesMap);
            var rawClips = this.parseAnimStacks(layersMap);

            return rawClips;

        },

        // parse nodes in FBXTree.Objects.AnimationCurveNode
        // each AnimationCurveNode holds data for an animation transform for a model (e.g. left arm rotation )
        // and is referenced by an AnimationLayer
        parseAnimationCurveNodes: function () {

            var rawCurveNodes = fbxTree.Objects.AnimationCurveNode;

            var curveNodesMap = new Map();

            for (var nodeID in rawCurveNodes) {

                var rawCurveNode = rawCurveNodes[nodeID];

                if (rawCurveNode.attrName.match(/S|R|T|DeformPercent/) !== null) {

                    var curveNode = {

                        id: rawCurveNode.id,
                        attr: rawCurveNode.attrName,
                        curves: {},

                    };

                    curveNodesMap.set(curveNode.id, curveNode);

                }

            }

            return curveNodesMap;

        },

        // parse nodes in FBXTree.Objects.AnimationCurve and connect them up to
        // previously parsed AnimationCurveNodes. Each AnimationCurve holds data for a single animated
        // axis ( e.g. times and values of x rotation)
        parseAnimationCurves: function (curveNodesMap) {

            var rawCurves = fbxTree.Objects.AnimationCurve;

            // TODO: Many values are identical up to roundoff error, but won't be optimised
            // e.g. position times: [0, 0.4, 0. 8]
            // position values: [7.23538335023477e-7, 93.67518615722656, -0.9982695579528809, 7.23538335023477e-7, 93.67518615722656, -0.9982695579528809, 7.235384487103147e-7, 93.67520904541016, -0.9982695579528809]
            // clearly, this should be optimised to
            // times: [0], positions [7.23538335023477e-7, 93.67518615722656, -0.9982695579528809]
            // this shows up in nearly every FBX file, and generally time array is length > 100

            for (var nodeID in rawCurves) {

                var animationCurve = {

                    id: rawCurves[nodeID].id,
                    times: rawCurves[nodeID].KeyTime.a.map(convertFBXTimeToSeconds),
                    values: rawCurves[nodeID].KeyValueFloat.a,

                };

                var relationships = connections.get(animationCurve.id);

                if (relationships !== undefined) {

                    var animationCurveID = relationships.parents[0].ID;
                    var animationCurveRelationship = relationships.parents[0].relationship;

                    if (animationCurveRelationship.match(/X/)) {

                        curveNodesMap.get(animationCurveID).curves['x'] = animationCurve;

                    } else if (animationCurveRelationship.match(/Y/)) {

                        curveNodesMap.get(animationCurveID).curves['y'] = animationCurve;

                    } else if (animationCurveRelationship.match(/Z/)) {

                        curveNodesMap.get(animationCurveID).curves['z'] = animationCurve;

                    } else if (animationCurveRelationship.match(/d|DeformPercent/) && curveNodesMap.has(animationCurveID)) {

                        curveNodesMap.get(animationCurveID).curves['morph'] = animationCurve;

                    }

                }

            }

        },

        // parse nodes in FBXTree.Objects.AnimationLayer. Each layers holds references
        // to various AnimationCurveNodes and is referenced by an AnimationStack node
        // note: theoretically a stack can have multiple layers, however in practice there always seems to be one per stack
        parseAnimationLayers: function (curveNodesMap) {

            var rawLayers = fbxTree.Objects.AnimationLayer;

            var layersMap = new Map();

            for (var nodeID in rawLayers) {

                var layerCurveNodes = [];

                var connection = connections.get(parseInt(nodeID));

                if (connection !== undefined) {

                    // all the animationCurveNodes used in the layer
                    var children = connection.children;

                    var self = this;
                    children.forEach(function (child, i) {

                        if (curveNodesMap.has(child.ID)) {

                            var curveNode = curveNodesMap.get(child.ID);

                            // check that the curves are defined for at least one axis, otherwise ignore the curveNode
                            if (curveNode.curves.x !== undefined || curveNode.curves.y !== undefined || curveNode.curves.z !== undefined) {

                                if (layerCurveNodes[i] === undefined) {

                                    var modelID;

                                    connections.get(child.ID).parents.forEach(function (parent) {

                                        if (parent.relationship !== undefined) modelID = parent.ID;

                                    });

                                    var rawModel = fbxTree.Objects.Model[modelID.toString()];

                                    var node = {

                                        modelName: THREE.PropertyBinding.sanitizeNodeName(rawModel.attrName),
                                        initialPosition: [0, 0, 0],
                                        initialRotation: [0, 0, 0],
                                        initialScale: [1, 1, 1],
                                        transform: self.getModelAnimTransform(rawModel),

                                    };

                                    // if the animated model is pre rotated, we'll have to apply the pre rotations to every
                                    // animation value as well
                                    if ('PreRotation' in rawModel) node.preRotations = rawModel.PreRotation.value;
                                    if ('PostRotation' in rawModel) node.postRotations = rawModel.PostRotation.value;

                                    layerCurveNodes[i] = node;

                                }

                                layerCurveNodes[i][curveNode.attr] = curveNode;

                            } else if (curveNode.curves.morph !== undefined) {

                                if (layerCurveNodes[i] === undefined) {

                                    var deformerID;

                                    connections.get(child.ID).parents.forEach(function (parent) {

                                        if (parent.relationship !== undefined) deformerID = parent.ID;

                                    });

                                    var morpherID = connections.get(deformerID).parents[0].ID;
                                    var geoID = connections.get(morpherID).parents[0].ID;

                                    // assuming geometry is not used in more than one model
                                    var modelID = connections.get(geoID).parents[0].ID;

                                    var rawModel = fbxTree.Objects.Model[modelID];

                                    var node = {

                                        modelName: THREE.PropertyBinding.sanitizeNodeName(rawModel.attrName),
                                        morphName: fbxTree.Objects.Deformer[deformerID].attrName,

                                    };

                                    layerCurveNodes[i] = node;

                                }

                                layerCurveNodes[i][curveNode.attr] = curveNode;

                            }

                        }

                    });

                    layersMap.set(parseInt(nodeID), layerCurveNodes);

                }

            }

            return layersMap;

        },

        getModelAnimTransform: function (modelNode) {

            var transformData = {};

            if ('RotationOrder' in modelNode) transformData.eulerOrder = parseInt(modelNode.RotationOrder.value);

            if ('Lcl_Translation' in modelNode) transformData.translation = modelNode.Lcl_Translation.value;
            if ('RotationOffset' in modelNode) transformData.rotationOffset = modelNode.RotationOffset.value;

            if ('Lcl_Rotation' in modelNode) transformData.rotation = modelNode.Lcl_Rotation.value;
            if ('PreRotation' in modelNode) transformData.preRotation = modelNode.PreRotation.value;

            if ('PostRotation' in modelNode) transformData.postRotation = modelNode.PostRotation.value;

            if ('Lcl_Scaling' in modelNode) transformData.scale = modelNode.Lcl_Scaling.value;

            return generateTransform(transformData);

        },

        // parse nodes in FBXTree.Objects.AnimationStack. These are the top level node in the animation
        // hierarchy. Each Stack node will be used to create a THREE.AnimationClip
        parseAnimStacks: function (layersMap) {

            var rawStacks = fbxTree.Objects.AnimationStack;

            // connect the stacks (clips) up to the layers
            var rawClips = {};

            for (var nodeID in rawStacks) {

                var children = connections.get(parseInt(nodeID)).children;

                if (children.length > 1) {

                    // it seems like stacks will always be associated with a single layer. But just in case there are files
                    // where there are multiple layers per stack, we'll display a warning
                    console.warn('THREE.FBXLoader: Encountered an animation stack with multiple layers, this is currently not supported. Ignoring subsequent layers.');

                }

                var layer = layersMap.get(children[0].ID);

                rawClips[nodeID] = {

                    name: rawStacks[nodeID].attrName,
                    layer: layer,

                };

            }

            return rawClips;

        },

        addClip: function (rawClip) {

            var tracks = [];

            var self = this;
            rawClip.layer.forEach(function (rawTracks) {

                tracks = tracks.concat(self.generateTracks(rawTracks));

            });

            return new THREE.AnimationClip(rawClip.name, -1, tracks);

        },

        generateTracks: function (rawTracks) {

            var tracks = [];

            var initialPosition = new THREE.Vector3();
            var initialRotation = new THREE.Quaternion();
            var initialScale = new THREE.Vector3();

            if (rawTracks.transform) rawTracks.transform.decompose(initialPosition, initialRotation, initialScale);

            initialPosition = initialPosition.toArray();
            initialRotation = new THREE.Euler().setFromQuaternion(initialRotation).toArray(); // todo: euler order
            initialScale = initialScale.toArray();

            if (rawTracks.T !== undefined && Object.keys(rawTracks.T.curves).length > 0) {

                var positionTrack = this.generateVectorTrack(rawTracks.modelName, rawTracks.T.curves, initialPosition, 'position');
                if (positionTrack !== undefined) tracks.push(positionTrack);

            }

            if (rawTracks.R !== undefined && Object.keys(rawTracks.R.curves).length > 0) {

                var rotationTrack = this.generateRotationTrack(rawTracks.modelName, rawTracks.R.curves, initialRotation, rawTracks.preRotations, rawTracks.postRotations);
                if (rotationTrack !== undefined) tracks.push(rotationTrack);

            }

            if (rawTracks.S !== undefined && Object.keys(rawTracks.S.curves).length > 0) {

                var scaleTrack = this.generateVectorTrack(rawTracks.modelName, rawTracks.S.curves, initialScale, 'scale');
                if (scaleTrack !== undefined) tracks.push(scaleTrack);

            }

            if (rawTracks.DeformPercent !== undefined) {

                var morphTrack = this.generateMorphTrack(rawTracks);
                if (morphTrack !== undefined) tracks.push(morphTrack);

            }

            return tracks;

        },

        generateVectorTrack: function (modelName, curves, initialValue, type) {

            var times = this.getTimesForAllAxes(curves);
            var values = this.getKeyframeTrackValues(times, curves, initialValue);

            return new THREE.VectorKeyframeTrack(modelName + '.' + type, times, values);

        },

        generateRotationTrack: function (modelName, curves, initialValue, preRotations, postRotations) {

            if (curves.x !== undefined) {

                this.interpolateRotations(curves.x);
                curves.x.values = curves.x.values.map(THREE.Math.degToRad);

            }
            if (curves.y !== undefined) {

                this.interpolateRotations(curves.y);
                curves.y.values = curves.y.values.map(THREE.Math.degToRad);

            }
            if (curves.z !== undefined) {

                this.interpolateRotations(curves.z);
                curves.z.values = curves.z.values.map(THREE.Math.degToRad);

            }

            var times = this.getTimesForAllAxes(curves);
            var values = this.getKeyframeTrackValues(times, curves, initialValue);

            if (preRotations !== undefined) {

                preRotations = preRotations.map(THREE.Math.degToRad);
                preRotations.push('ZYX');

                preRotations = new THREE.Euler().fromArray(preRotations);
                preRotations = new THREE.Quaternion().setFromEuler(preRotations);

            }

            if (postRotations !== undefined) {

                postRotations = postRotations.map(THREE.Math.degToRad);
                postRotations.push('ZYX');

                postRotations = new THREE.Euler().fromArray(postRotations);
                postRotations = new THREE.Quaternion().setFromEuler(postRotations).inverse();

            }

            var quaternion = new THREE.Quaternion();
            var euler = new THREE.Euler();

            var quaternionValues = [];

            for (var i = 0; i < values.length; i += 3) {

                euler.set(values[i], values[i + 1], values[i + 2], 'ZYX');

                quaternion.setFromEuler(euler);

                if (preRotations !== undefined) quaternion.premultiply(preRotations);
                if (postRotations !== undefined) quaternion.multiply(postRotations);

                quaternion.toArray(quaternionValues, (i / 3) * 4);

            }

            return new THREE.QuaternionKeyframeTrack(modelName + '.quaternion', times, quaternionValues);

        },

        generateMorphTrack: function (rawTracks) {

            var curves = rawTracks.DeformPercent.curves.morph;
            var values = curves.values.map(function (val) {

                return val / 100;

            });

            var morphNum = sceneGraph.getObjectByName(rawTracks.modelName).morphTargetDictionary[rawTracks.morphName];

            return new THREE.NumberKeyframeTrack(rawTracks.modelName + '.morphTargetInfluences[' + morphNum + ']', curves.times, values);

        },

        // For all animated objects, times are defined separately for each axis
        // Here we'll combine the times into one sorted array without duplicates
        getTimesForAllAxes: function (curves) {

            var times = [];

            // first join together the times for each axis, if defined
            if (curves.x !== undefined) times = times.concat(curves.x.times);
            if (curves.y !== undefined) times = times.concat(curves.y.times);
            if (curves.z !== undefined) times = times.concat(curves.z.times);

            // then sort them and remove duplicates
            times = times.sort(function (a, b) {

                return a - b;

            }).filter(function (elem, index, array) {

                return array.indexOf(elem) == index;

            });

            return times;

        },

        getKeyframeTrackValues: function (times, curves, initialValue) {

            var prevValue = initialValue;

            var values = [];

            var xIndex = -1;
            var yIndex = -1;
            var zIndex = -1;

            times.forEach(function (time) {

                if (curves.x) xIndex = curves.x.times.indexOf(time);
                if (curves.y) yIndex = curves.y.times.indexOf(time);
                if (curves.z) zIndex = curves.z.times.indexOf(time);

                // if there is an x value defined for this frame, use that
                if (xIndex !== -1) {

                    var xValue = curves.x.values[xIndex];
                    values.push(xValue);
                    prevValue[0] = xValue;

                } else {

                    // otherwise use the x value from the previous frame
                    values.push(prevValue[0]);

                }

                if (yIndex !== -1) {

                    var yValue = curves.y.values[yIndex];
                    values.push(yValue);
                    prevValue[1] = yValue;

                } else {

                    values.push(prevValue[1]);

                }

                if (zIndex !== -1) {

                    var zValue = curves.z.values[zIndex];
                    values.push(zValue);
                    prevValue[2] = zValue;

                } else {

                    values.push(prevValue[2]);

                }

            });

            return values;

        },

        // Rotations are defined as Euler angles which can have values  of any size
        // These will be converted to quaternions which don't support values greater than
        // PI, so we'll interpolate large rotations
        interpolateRotations: function (curve) {

            for (var i = 1; i < curve.values.length; i++) {

                var initialValue = curve.values[i - 1];
                var valuesSpan = curve.values[i] - initialValue;

                var absoluteSpan = Math.abs(valuesSpan);

                if (absoluteSpan >= 180) {

                    var numSubIntervals = absoluteSpan / 180;

                    var step = valuesSpan / numSubIntervals;
                    var nextValue = initialValue + step;

                    var initialTime = curve.times[i - 1];
                    var timeSpan = curve.times[i] - initialTime;
                    var interval = timeSpan / numSubIntervals;
                    var nextTime = initialTime + interval;

                    var interpolatedTimes = [];
                    var interpolatedValues = [];

                    while (nextTime < curve.times[i]) {

                        interpolatedTimes.push(nextTime);
                        nextTime += interval;

                        interpolatedValues.push(nextValue);
                        nextValue += step;

                    }

                    curve.times = inject(curve.times, i, interpolatedTimes);
                    curve.values = inject(curve.values, i, interpolatedValues);

                }

            }

        },

    };

    // parse an FBX file in ASCII format
    function TextParser() { }

    TextParser.prototype = {

        constructor: TextParser,

        getPrevNode: function () {

            return this.nodeStack[this.currentIndent - 2];

        },

        getCurrentNode: function () {

            return this.nodeStack[this.currentIndent - 1];

        },

        getCurrentProp: function () {

            return this.currentProp;

        },

        pushStack: function (node) {

            this.nodeStack.push(node);
            this.currentIndent += 1;

        },

        popStack: function () {

            this.nodeStack.pop();
            this.currentIndent -= 1;

        },

        setCurrentProp: function (val, name) {

            this.currentProp = val;
            this.currentPropName = name;

        },

        parse: function (text) {

            this.currentIndent = 0;
            console.log("FBXTree: ", FBXTree);
            this.allNodes = new FBXTree();
            this.nodeStack = [];
            this.currentProp = [];
            this.currentPropName = '';

            var self = this;

            var split = text.split(/[\r\n]+/);

            split.forEach(function (line, i) {

                var matchComment = line.match(/^[\s\t]*;/);
                var matchEmpty = line.match(/^[\s\t]*$/);

                if (matchComment || matchEmpty) return;

                var matchBeginning = line.match('^\\t{' + self.currentIndent + '}(\\w+):(.*){', '');
                var matchProperty = line.match('^\\t{' + (self.currentIndent) + '}(\\w+):[\\s\\t\\r\\n](.*)');
                var matchEnd = line.match('^\\t{' + (self.currentIndent - 1) + '}}');

                if (matchBeginning) {

                    self.parseNodeBegin(line, matchBeginning);

                } else if (matchProperty) {

                    self.parseNodeProperty(line, matchProperty, split[++i]);

                } else if (matchEnd) {

                    self.popStack();

                } else if (line.match(/^[^\s\t}]/)) {

                    // large arrays are split over multiple lines terminated with a ',' character
                    // if this is encountered the line needs to be joined to the previous line
                    self.parseNodePropertyContinued(line);

                }

            });

            return this.allNodes;

        },

        parseNodeBegin: function (line, property) {

            var nodeName = property[1].trim().replace(/^"/, '').replace(/"$/, '');

            var nodeAttrs = property[2].split(',').map(function (attr) {

                return attr.trim().replace(/^"/, '').replace(/"$/, '');

            });

            var node = { name: nodeName };
            var attrs = this.parseNodeAttr(nodeAttrs);

            var currentNode = this.getCurrentNode();

            // a top node
            if (this.currentIndent === 0) {

                this.allNodes.add(nodeName, node);

            } else { // a subnode

                // if the subnode already exists, append it
                if (nodeName in currentNode) {

                    // special case Pose needs PoseNodes as an array
                    if (nodeName === 'PoseNode') {

                        currentNode.PoseNode.push(node);

                    } else if (currentNode[nodeName].id !== undefined) {

                        currentNode[nodeName] = {};
                        currentNode[nodeName][currentNode[nodeName].id] = currentNode[nodeName];

                    }

                    if (attrs.id !== '') currentNode[nodeName][attrs.id] = node;

                } else if (typeof attrs.id === 'number') {

                    currentNode[nodeName] = {};
                    currentNode[nodeName][attrs.id] = node;

                } else if (nodeName !== 'Properties70') {

                    if (nodeName === 'PoseNode') currentNode[nodeName] = [node];
                    else currentNode[nodeName] = node;

                }

            }

            if (typeof attrs.id === 'number') node.id = attrs.id;
            if (attrs.name !== '') node.attrName = attrs.name;
            if (attrs.type !== '') node.attrType = attrs.type;

            this.pushStack(node);

        },

        parseNodeAttr: function (attrs) {

            var id = attrs[0];

            if (attrs[0] !== '') {

                id = parseInt(attrs[0]);

                if (isNaN(id)) {

                    id = attrs[0];

                }

            }

            var name = '', type = '';

            if (attrs.length > 1) {

                name = attrs[1].replace(/^(\w+)::/, '');
                type = attrs[2];

            }

            return { id: id, name: name, type: type };

        },

        parseNodeProperty: function (line, property, contentLine) {

            var propName = property[1].replace(/^"/, '').replace(/"$/, '').trim();
            var propValue = property[2].replace(/^"/, '').replace(/"$/, '').trim();

            // for special case: base64 image data follows "Content: ," line
            //	Content: ,
            //	 "/9j/4RDaRXhpZgAATU0A..."
            if (propName === 'Content' && propValue === ',') {

                propValue = contentLine.replace(/"/g, '').replace(/,$/, '').trim();

            }

            var currentNode = this.getCurrentNode();
            var parentName = currentNode.name;

            if (parentName === 'Properties70') {

                this.parseNodeSpecialProperty(line, propName, propValue);
                return;

            }

            // Connections
            if (propName === 'C') {

                var connProps = propValue.split(',').slice(1);
                var from = parseInt(connProps[0]);
                var to = parseInt(connProps[1]);

                var rest = propValue.split(',').slice(3);

                rest = rest.map(function (elem) {

                    return elem.trim().replace(/^"/, '');

                });

                propName = 'connections';
                propValue = [from, to];
                append(propValue, rest);

                if (currentNode[propName] === undefined) {

                    currentNode[propName] = [];

                }

            }

            // Node
            if (propName === 'Node') currentNode.id = propValue;

            // connections
            if (propName in currentNode && Array.isArray(currentNode[propName])) {

                currentNode[propName].push(propValue);

            } else {

                if (propName !== 'a') currentNode[propName] = propValue;
                else currentNode.a = propValue;

            }

            this.setCurrentProp(currentNode, propName);

            // convert string to array, unless it ends in ',' in which case more will be added to it
            if (propName === 'a' && propValue.slice(-1) !== ',') {

                currentNode.a = parseNumberArray(propValue);

            }

        },

        parseNodePropertyContinued: function (line) {

            var currentNode = this.getCurrentNode();

            currentNode.a += line;

            // if the line doesn't end in ',' we have reached the end of the property value
            // so convert the string to an array
            if (line.slice(-1) !== ',') {

                currentNode.a = parseNumberArray(currentNode.a);

            }

        },

        // parse "Property70"
        parseNodeSpecialProperty: function (line, propName, propValue) {

            // split this
            // P: "Lcl Scaling", "Lcl Scaling", "", "A",1,1,1
            // into array like below
            // ["Lcl Scaling", "Lcl Scaling", "", "A", "1,1,1" ]
            var props = propValue.split('",').map(function (prop) {

                return prop.trim().replace(/^\"/, '').replace(/\s/, '_');

            });

            var innerPropName = props[0];
            var innerPropType1 = props[1];
            var innerPropType2 = props[2];
            var innerPropFlag = props[3];
            var innerPropValue = props[4];

            // cast values where needed, otherwise leave as strings
            switch (innerPropType1) {

                case 'int':
                case 'enum':
                case 'bool':
                case 'ULongLong':
                case 'double':
                case 'Number':
                case 'FieldOfView':
                    innerPropValue = parseFloat(innerPropValue);
                    break;

                case 'Color':
                case 'ColorRGB':
                case 'Vector3D':
                case 'Lcl_Translation':
                case 'Lcl_Rotation':
                case 'Lcl_Scaling':
                    innerPropValue = parseNumberArray(innerPropValue);
                    break;

            }

            // CAUTION: these props must append to parent's parent
            this.getPrevNode()[innerPropName] = {

                'type': innerPropType1,
                'type2': innerPropType2,
                'flag': innerPropFlag,
                'value': innerPropValue

            };

            this.setCurrentProp(this.getPrevNode(), innerPropName);

        },

    };

    // Parse an FBX file in Binary format
    function BinaryParser() { }

    BinaryParser.prototype = {

        constructor: BinaryParser,

        parse: function (buffer) {

            var reader = new BinaryReader(buffer);
            reader.skip(23); // skip magic 23 bytes

            var version = reader.getUint32();

            console.log('THREE.FBXLoader: FBX binary version: ' + version);

            var allNodes = new FBXTree();

            while (!this.endOfContent(reader)) {

                var node = this.parseNode(reader, version);
                if (node !== null) allNodes.add(node.name, node);

            }

            return allNodes;

        },

        // Check if reader has reached the end of content.
        endOfContent: function (reader) {

            // footer size: 160bytes + 16-byte alignment padding
            // - 16bytes: magic
            // - padding til 16-byte alignment (at least 1byte?)
            //	(seems like some exporters embed fixed 15 or 16bytes?)
            // - 4bytes: magic
            // - 4bytes: version
            // - 120bytes: zero
            // - 16bytes: magic
            if (reader.size() % 16 === 0) {

                return ((reader.getOffset() + 160 + 16) & ~0xf) >= reader.size();

            } else {

                return reader.getOffset() + 160 + 16 >= reader.size();

            }

        },

        // recursively parse nodes until the end of the file is reached
        parseNode: function (reader, version) {

            var node = {};

            // The first three data sizes depends on version.
            var endOffset = (version >= 7500) ? reader.getUint64() : reader.getUint32();
            var numProperties = (version >= 7500) ? reader.getUint64() : reader.getUint32();

            // note: do not remove this even if you get a linter warning as it moves the buffer forward
            var propertyListLen = (version >= 7500) ? reader.getUint64() : reader.getUint32();

            var nameLen = reader.getUint8();
            var name = reader.getString(nameLen);

            // Regards this node as NULL-record if endOffset is zero
            if (endOffset === 0) return null;

            var propertyList = [];

            for (var i = 0; i < numProperties; i++) {

                propertyList.push(this.parseProperty(reader));

            }

            // Regards the first three elements in propertyList as id, attrName, and attrType
            var id = propertyList.length > 0 ? propertyList[0] : '';
            var attrName = propertyList.length > 1 ? propertyList[1] : '';
            var attrType = propertyList.length > 2 ? propertyList[2] : '';

            // check if this node represents just a single property
            // like (name, 0) set or (name2, [0, 1, 2]) set of {name: 0, name2: [0, 1, 2]}
            node.singleProperty = (numProperties === 1 && reader.getOffset() === endOffset) ? true : false;

            while (endOffset > reader.getOffset()) {

                var subNode = this.parseNode(reader, version);

                if (subNode !== null) this.parseSubNode(name, node, subNode);

            }

            node.propertyList = propertyList; // raw property list used by parent

            if (typeof id === 'number') node.id = id;
            if (attrName !== '') node.attrName = attrName;
            if (attrType !== '') node.attrType = attrType;
            if (name !== '') node.name = name;

            return node;

        },

        parseSubNode: function (name, node, subNode) {

            // special case: child node is single property
            if (subNode.singleProperty === true) {

                var value = subNode.propertyList[0];

                if (Array.isArray(value)) {

                    node[subNode.name] = subNode;

                    subNode.a = value;

                } else {

                    node[subNode.name] = value;

                }

            } else if (name === 'Connections' && subNode.name === 'C') {

                var array = [];

                subNode.propertyList.forEach(function (property, i) {

                    // first Connection is FBX type (OO, OP, etc.). We'll discard these
                    if (i !== 0) array.push(property);

                });

                if (node.connections === undefined) {

                    node.connections = [];

                }

                node.connections.push(array);

            } else if (subNode.name === 'Properties70') {

                var keys = Object.keys(subNode);

                keys.forEach(function (key) {

                    node[key] = subNode[key];

                });

            } else if (name === 'Properties70' && subNode.name === 'P') {

                var innerPropName = subNode.propertyList[0];
                var innerPropType1 = subNode.propertyList[1];
                var innerPropType2 = subNode.propertyList[2];
                var innerPropFlag = subNode.propertyList[3];
                var innerPropValue;

                if (innerPropName.indexOf('Lcl ') === 0) innerPropName = innerPropName.replace('Lcl ', 'Lcl_');
                if (innerPropType1.indexOf('Lcl ') === 0) innerPropType1 = innerPropType1.replace('Lcl ', 'Lcl_');

                if (innerPropType1 === 'Color' || innerPropType1 === 'ColorRGB' || innerPropType1 === 'Vector' || innerPropType1 === 'Vector3D' || innerPropType1.indexOf('Lcl_') === 0) {

                    innerPropValue = [
						subNode.propertyList[4],
						subNode.propertyList[5],
						subNode.propertyList[6]
                    ];

                } else {

                    innerPropValue = subNode.propertyList[4];

                }

                // this will be copied to parent, see above
                node[innerPropName] = {

                    'type': innerPropType1,
                    'type2': innerPropType2,
                    'flag': innerPropFlag,
                    'value': innerPropValue

                };

            } else if (node[subNode.name] === undefined) {

                if (typeof subNode.id === 'number') {

                    node[subNode.name] = {};
                    node[subNode.name][subNode.id] = subNode;

                } else {

                    node[subNode.name] = subNode;

                }

            } else {

                if (subNode.name === 'PoseNode') {

                    if (!Array.isArray(node[subNode.name])) {

                        node[subNode.name] = [node[subNode.name]];

                    }

                    node[subNode.name].push(subNode);

                } else if (node[subNode.name][subNode.id] === undefined) {

                    node[subNode.name][subNode.id] = subNode;

                }

            }

        },

        parseProperty: function (reader) {

            var type = reader.getString(1);

            switch (type) {

                case 'C':
                    return reader.getBoolean();

                case 'D':
                    return reader.getFloat64();

                case 'F':
                    return reader.getFloat32();

                case 'I':
                    return reader.getInt32();

                case 'L':
                    return reader.getInt64();

                case 'R':
                    var length = reader.getUint32();
                    return reader.getArrayBuffer(length);

                case 'S':
                    var length = reader.getUint32();
                    return reader.getString(length);

                case 'Y':
                    return reader.getInt16();

                case 'b':
                case 'c':
                case 'd':
                case 'f':
                case 'i':
                case 'l':

                    var arrayLength = reader.getUint32();
                    var encoding = reader.getUint32(); // 0: non-compressed, 1: compressed
                    var compressedLength = reader.getUint32();

                    if (encoding === 0) {

                        switch (type) {

                            case 'b':
                            case 'c':
                                return reader.getBooleanArray(arrayLength);

                            case 'd':
                                return reader.getFloat64Array(arrayLength);

                            case 'f':
                                return reader.getFloat32Array(arrayLength);

                            case 'i':
                                return reader.getInt32Array(arrayLength);

                            case 'l':
                                return reader.getInt64Array(arrayLength);

                        }

                    }

                    if (typeof Zlib === 'undefined') {

                        console.error('THREE.FBXLoader: External library Inflate.min.js required, obtain or import from https://github.com/imaya/zlib.js');

                    }

                    var inflate = new Zlib.Inflate(new Uint8Array(reader.getArrayBuffer(compressedLength))); // eslint-disable-line no-undef
                    var reader2 = new BinaryReader(inflate.decompress().buffer);

                    switch (type) {

                        case 'b':
                        case 'c':
                            return reader2.getBooleanArray(arrayLength);

                        case 'd':
                            return reader2.getFloat64Array(arrayLength);

                        case 'f':
                            return reader2.getFloat32Array(arrayLength);

                        case 'i':
                            return reader2.getInt32Array(arrayLength);

                        case 'l':
                            return reader2.getInt64Array(arrayLength);

                    }

                default:
                    throw new Error('THREE.FBXLoader: Unknown property type ' + type);

            }

        }

    };

    function BinaryReader(buffer, littleEndian) {

        this.dv = new DataView(buffer);
        this.offset = 0;
        this.littleEndian = (littleEndian !== undefined) ? littleEndian : true;

    }

    BinaryReader.prototype = {

        constructor: BinaryReader,

        getOffset: function () {

            return this.offset;

        },

        size: function () {

            return this.dv.buffer.byteLength;

        },

        skip: function (length) {

            this.offset += length;

        },

        // seems like true/false representation depends on exporter.
        // true: 1 or 'Y'(=0x59), false: 0 or 'T'(=0x54)
        // then sees LSB.
        getBoolean: function () {

            return (this.getUint8() & 1) === 1;

        },

        getBooleanArray: function (size) {

            var a = [];

            for (var i = 0; i < size; i++) {

                a.push(this.getBoolean());

            }

            return a;

        },

        getUint8: function () {

            var value = this.dv.getUint8(this.offset);
            this.offset += 1;
            return value;

        },

        getInt16: function () {

            var value = this.dv.getInt16(this.offset, this.littleEndian);
            this.offset += 2;
            return value;

        },

        getInt32: function () {

            var value = this.dv.getInt32(this.offset, this.littleEndian);
            this.offset += 4;
            return value;

        },

        getInt32Array: function (size) {

            var a = [];

            for (var i = 0; i < size; i++) {

                a.push(this.getInt32());

            }

            return a;

        },

        getUint32: function () {

            var value = this.dv.getUint32(this.offset, this.littleEndian);
            this.offset += 4;
            return value;

        },

        // JavaScript doesn't support 64-bit integer so calculate this here
        // 1 << 32 will return 1 so using multiply operation instead here.
        // There's a possibility that this method returns wrong value if the value
        // is out of the range between Number.MAX_SAFE_INTEGER and Number.MIN_SAFE_INTEGER.
        // TODO: safely handle 64-bit integer
        getInt64: function () {

            var low, high;

            if (this.littleEndian) {

                low = this.getUint32();
                high = this.getUint32();

            } else {

                high = this.getUint32();
                low = this.getUint32();

            }

            // calculate negative value
            if (high & 0x80000000) {

                high = ~high & 0xFFFFFFFF;
                low = ~low & 0xFFFFFFFF;

                if (low === 0xFFFFFFFF) high = (high + 1) & 0xFFFFFFFF;

                low = (low + 1) & 0xFFFFFFFF;

                return -(high * 0x100000000 + low);

            }

            return high * 0x100000000 + low;

        },

        getInt64Array: function (size) {

            var a = [];

            for (var i = 0; i < size; i++) {

                a.push(this.getInt64());

            }

            return a;

        },

        // Note: see getInt64() comment
        getUint64: function () {

            var low, high;

            if (this.littleEndian) {

                low = this.getUint32();
                high = this.getUint32();

            } else {

                high = this.getUint32();
                low = this.getUint32();

            }

            return high * 0x100000000 + low;

        },

        getFloat32: function () {

            var value = this.dv.getFloat32(this.offset, this.littleEndian);
            this.offset += 4;
            return value;

        },

        getFloat32Array: function (size) {

            var a = [];

            for (var i = 0; i < size; i++) {

                a.push(this.getFloat32());

            }

            return a;

        },

        getFloat64: function () {

            var value = this.dv.getFloat64(this.offset, this.littleEndian);
            this.offset += 8;
            return value;

        },

        getFloat64Array: function (size) {

            var a = [];

            for (var i = 0; i < size; i++) {

                a.push(this.getFloat64());

            }

            return a;

        },

        getArrayBuffer: function (size) {

            var value = this.dv.buffer.slice(this.offset, this.offset + size);
            this.offset += size;
            return value;

        },

        getString: function (size) {

            // note: safari 9 doesn't support Uint8Array.indexOf; create intermediate array instead
            var a = [];

            for (var i = 0; i < size; i++) {

                a[i] = this.getUint8();

            }

            var nullByte = a.indexOf(0);
            if (nullByte >= 0) a = a.slice(0, nullByte);

            return THREE.LoaderUtils.decodeText(new Uint8Array(a));

        }

    };

    // FBXTree holds a representation of the FBX data, returned by the TextParser ( FBX ASCII format)
    // and BinaryParser( FBX Binary format)
    function FBXTree() { }

    FBXTree.prototype = {

        constructor: FBXTree,

        add: function (key, val) {

            this[key] = val;

        },

    };

    // ************** UTILITY FUNCTIONS **************

    function isFbxFormatBinary(buffer) {

        var CORRECT = 'Kaydara FBX Binary  \0';

        return buffer.byteLength >= CORRECT.length && CORRECT === convertArrayBufferToString(buffer, 0, CORRECT.length);

    }

    function isFbxFormatASCII(text) {

        var CORRECT = ['K', 'a', 'y', 'd', 'a', 'r', 'a', '\\', 'F', 'B', 'X', '\\', 'B', 'i', 'n', 'a', 'r', 'y', '\\', '\\'];

        var cursor = 0;

        function read(offset) {

            var result = text[offset - 1];
            text = text.slice(cursor + offset);
            cursor++;
            return result;

        }

        for (var i = 0; i < CORRECT.length; ++i) {

            var num = read(1);
            if (num === CORRECT[i]) {

                return false;

            }

        }

        return true;

    }

    function getFbxVersion(text) {

        var versionRegExp = /FBXVersion: (\d+)/;
        var match = text.match(versionRegExp);
        if (match) {

            var version = parseInt(match[1]);
            return version;

        }
        throw new Error('THREE.FBXLoader: Cannot find the version number for the file given.');

    }

    // Converts FBX ticks into real time seconds.
    function convertFBXTimeToSeconds(time) {

        return time / 46186158000;

    }

    var dataArray = [];

    // extracts the data from the correct position in the FBX array based on indexing type
    function getData(polygonVertexIndex, polygonIndex, vertexIndex, infoObject) {

        var index;

        switch (infoObject.mappingType) {

            case 'ByPolygonVertex':
                index = polygonVertexIndex;
                break;
            case 'ByPolygon':
                index = polygonIndex;
                break;
            case 'ByVertice':
                index = vertexIndex;
                break;
            case 'AllSame':
                index = infoObject.indices[0];
                break;
            default:
                console.warn('THREE.FBXLoader: unknown attribute mapping type ' + infoObject.mappingType);

        }

        if (infoObject.referenceType === 'IndexToDirect') index = infoObject.indices[index];

        var from = index * infoObject.dataSize;
        var to = from + infoObject.dataSize;

        return slice(dataArray, infoObject.buffer, from, to);

    }

    var tempMat = new THREE.Matrix4();
    var tempEuler = new THREE.Euler();
    var tempVec = new THREE.Vector3();
    var translation = new THREE.Vector3();
    var rotation = new THREE.Matrix4();

    // generate transformation from FBX transform data
    // ref: https://help.autodesk.com/view/FBX/2017/ENU/?guid=__files_GUID_10CDD63C_79C1_4F2D_BB28_AD2BE65A02ED_htm
    // transformData = {
    //	 eulerOrder: int,
    //	 translation: [],
    //   rotationOffset: [],
    //	 preRotation
    //	 rotation
    //	 postRotation
    //   scale
    // }
    // all entries are optional
    function generateTransform(transformData) {

        var transform = new THREE.Matrix4();
        translation.set(0, 0, 0);
        rotation.identity();

        var order = (transformData.eulerOrder) ? getEulerOrder(transformData.eulerOrder) : getEulerOrder(0);

        if (transformData.translation) translation.fromArray(transformData.translation);
        if (transformData.rotationOffset) translation.add(tempVec.fromArray(transformData.rotationOffset));

        if (transformData.rotation) {

            var array = transformData.rotation.map(THREE.Math.degToRad);
            array.push(order);
            rotation.makeRotationFromEuler(tempEuler.fromArray(array));

        }

        if (transformData.preRotation) {

            var array = transformData.preRotation.map(THREE.Math.degToRad);
            array.push(order);
            tempMat.makeRotationFromEuler(tempEuler.fromArray(array));

            rotation.premultiply(tempMat);

        }

        if (transformData.postRotation) {

            var array = transformData.postRotation.map(THREE.Math.degToRad);
            array.push(order);
            tempMat.makeRotationFromEuler(tempEuler.fromArray(array));

            tempMat.getInverse(tempMat);

            rotation.multiply(tempMat);

        }

        if (transformData.scale) transform.scale(tempVec.fromArray(transformData.scale));

        transform.setPosition(translation);
        transform.multiply(rotation);

        return transform;

    }

    // Returns the three.js intrinsic Euler order corresponding to FBX extrinsic Euler order
    // ref: http://help.autodesk.com/view/FBX/2017/ENU/?guid=__cpp_ref_class_fbx_euler_html
    function getEulerOrder(order) {

        var enums = [
			'ZYX', // -> XYZ extrinsic
			'YZX', // -> XZY extrinsic
			'XZY', // -> YZX extrinsic
			'ZXY', // -> YXZ extrinsic
			'YXZ', // -> ZXY extrinsic
			'XYZ', // -> ZYX extrinsic
		//'SphericXYZ', // not possible to support
        ];

        if (order === 6) {

            console.warn('THREE.FBXLoader: unsupported Euler Order: Spherical XYZ. Animations and rotations may be incorrect.');
            return enums[0];

        }

        return enums[order];

    }

    // Parses comma separated list of numbers and returns them an array.
    // Used internally by the TextParser
    function parseNumberArray(value) {

        var array = value.split(',').map(function (val) {

            return parseFloat(val);

        });

        return array;

    }

    function convertArrayBufferToString(buffer, from, to) {

        if (from === undefined) from = 0;
        if (to === undefined) to = buffer.byteLength;

        return THREE.LoaderUtils.decodeText(new Uint8Array(buffer, from, to));

    }

    function append(a, b) {

        for (var i = 0, j = a.length, l = b.length; i < l; i++, j++) {

            a[j] = b[i];

        }

    }

    function slice(a, b, from, to) {

        for (var i = from, j = 0; i < to; i++, j++) {

            a[j] = b[i];

        }

        return a;

    }

    // inject array a2 into array a1 at index
    function inject(a1, index, a2) {

        return a1.slice(0, index).concat(a2).concat(a1.slice(index));

    }

    return FBXLoader;

})();
