Babylon.js/src/Meshes/mesh.ts

import { Observer, Observable } from "../Misc/observable";
import { Tools, AsyncLoop } from "../Misc/tools";
import { IAnimatable } from '../Animations/animatable.interface';
import { DeepCopier } from "../Misc/deepCopier";
import { Tags } from "../Misc/tags";
import { Nullable, FloatArray, IndicesArray } from "../types";
import { Camera } from "../Cameras/camera";
import { Scene } from "../scene";
import { Quaternion, Matrix, Vector3, Vector2, Vector4 } from "../Maths/math.vector";
import { Color3, Color4 } from '../Maths/math.color';
import { Engine } from "../Engines/engine";
import { Node } from "../node";
import { VertexBuffer } from "./buffer";
import { VertexData, IGetSetVerticesData } from "./mesh.vertexData";
import { Buffer } from "./buffer";
import { Geometry } from "./geometry";
import { AbstractMesh } from "./abstractMesh";
import { SubMesh } from "./subMesh";
import { BoundingInfo } from "../Culling/boundingInfo";
import { BoundingSphere } from "../Culling/boundingSphere";
import { Effect } from "../Materials/effect";
import { Material } from "../Materials/material";
import { MultiMaterial } from "../Materials/multiMaterial";
import { SceneLoaderFlags } from "../Loading/sceneLoaderFlags";
import { Skeleton } from "../Bones/skeleton";
import { MorphTargetManager } from "../Morph/morphTargetManager";
import { Constants } from "../Engines/constants";
import { SerializationHelper } from "../Misc/decorators";
import { Logger } from "../Misc/logger";
import { _TypeStore } from '../Misc/typeStore';
import { _DevTools } from '../Misc/devTools';
import { SceneComponentConstants } from "../sceneComponent";
import { MeshLODLevel } from './meshLODLevel';
import { Path3D } from '../Maths/math.path';
import { Plane } from '../Maths/math.plane';
import { TransformNode } from './transformNode';
import { CanvasGenerator } from '../Misc/canvasGenerator';
import { ICreateCapsuleOptions } from './Builders/capsuleBuilder';

declare type LinesMesh = import("./linesMesh").LinesMesh;
declare type InstancedMesh = import("./instancedMesh").InstancedMesh;
declare type GroundMesh = import("./groundMesh").GroundMesh;
declare type IPhysicsEnabledObject = import("../Physics/physicsImpostor").IPhysicsEnabledObject;
declare type PhysicsImpostor = import("../Physics/physicsImpostor").PhysicsImpostor;

declare var earcut: any;

/**
 * @hidden
 **/
export class _CreationDataStorage {
    public closePath?: boolean;
    public closeArray?: boolean;
    public idx: number[];
    public dashSize: number;
    public gapSize: number;
    public path3D: Path3D;
    public pathArray: Vector3[][];
    public arc: number;
    public radius: number;
    public cap: number;
    public tessellation: number;
}

/**
 * @hidden
 **/
class _InstanceDataStorage {
    public visibleInstances: any = {};
    public batchCache = new _InstancesBatch();
    public instancesBufferSize = 32 * 16 * 4; // let's start with a maximum of 32 instances
    public instancesBuffer: Nullable<Buffer>;
    public instancesData: Float32Array;
    public overridenInstanceCount: number;
    public isFrozen: boolean;
    public previousBatch: Nullable<_InstancesBatch>;
    public hardwareInstancedRendering: boolean;
    public sideOrientation: number;
    public manualUpdate: boolean;
    public previousRenderId: number;
}

/**
 * @hidden
 **/
export class _InstancesBatch {
    public mustReturn = false;
    public visibleInstances = new Array<Nullable<Array<InstancedMesh>>>();
    public renderSelf = new Array<boolean>();
    public hardwareInstancedRendering = new Array<boolean>();
}

/**
 * @hidden
 **/
class _ThinInstanceDataStorage {
    public instancesCount: number = 0;
    public matrixBuffer: Nullable<Buffer> = null;
    public matrixBufferSize = 32 * 16; // let's start with a maximum of 32 thin instances
    public matrixData: Nullable<Float32Array>;
    public boundingVectors: Array<Vector3> = [];
    public worldMatrices: Nullable<Matrix[]> = null;
}

/**
 * @hidden
 **/
class _InternalMeshDataInfo {
    // Events
    public _onBeforeRenderObservable: Nullable<Observable<Mesh>>;
    public _onBeforeBindObservable: Nullable<Observable<Mesh>>;
    public _onAfterRenderObservable: Nullable<Observable<Mesh>>;
    public _onBeforeDrawObservable: Nullable<Observable<Mesh>>;

    public _areNormalsFrozen: boolean = false; // Will be used by ribbons mainly
    public _sourcePositions: Float32Array; // Will be used to save original positions when using software skinning
    public _sourceNormals: Float32Array;   // Will be used to save original normals when using software skinning

    // Will be used to save a source mesh reference, If any
    public _source: Nullable<Mesh> = null;
    // Will be used to for fast cloned mesh lookup
    public meshMap: Nullable<{ [id: string]: Mesh | undefined }> = null;

    public _preActivateId: number = -1;
    public _LODLevels = new Array<MeshLODLevel>();

    // Morph
    public _morphTargetManager: Nullable<MorphTargetManager> = null;
}

/**
 * Class used to represent renderable models
 */
export class Mesh extends AbstractMesh implements IGetSetVerticesData {
    // Consts

    /**
     * Mesh side orientation : usually the external or front surface
     */
    public static readonly FRONTSIDE = VertexData.FRONTSIDE;

    /**
     * Mesh side orientation : usually the internal or back surface
     */
    public static readonly BACKSIDE = VertexData.BACKSIDE;
    /**
     * Mesh side orientation : both internal and external or front and back surfaces
     */
    public static readonly DOUBLESIDE = VertexData.DOUBLESIDE;
    /**
     * Mesh side orientation : by default, `FRONTSIDE`
     */
    public static readonly DEFAULTSIDE = VertexData.DEFAULTSIDE;
    /**
     * Mesh cap setting : no cap
     */
    public static readonly NO_CAP = 0;
    /**
     * Mesh cap setting : one cap at the beginning of the mesh
     */
    public static readonly CAP_START = 1;
    /**
     * Mesh cap setting : one cap at the end of the mesh
     */
    public static readonly CAP_END = 2;
    /**
     * Mesh cap setting : two caps, one at the beginning  and one at the end of the mesh
     */
    public static readonly CAP_ALL = 3;
    /**
     * Mesh pattern setting : no flip or rotate
     */
    public static readonly NO_FLIP = 0;
    /**
     * Mesh pattern setting : flip (reflect in y axis) alternate tiles on each row or column
     */
    public static readonly FLIP_TILE = 1;
    /**
     * Mesh pattern setting : rotate (180degs) alternate tiles on each row or column
     */
    public static readonly ROTATE_TILE = 2;
    /**
     * Mesh pattern setting : flip (reflect in y axis) all tiles on alternate rows
     */
    public static readonly FLIP_ROW = 3;
    /**
     * Mesh pattern setting : rotate (180degs) all tiles on alternate rows
     */
    public static readonly ROTATE_ROW = 4;
    /**
     * Mesh pattern setting : flip and rotate alternate tiles on each row or column
     */
    public static readonly FLIP_N_ROTATE_TILE = 5;
    /**
     * Mesh pattern setting : rotate pattern and rotate
     */
    public static readonly FLIP_N_ROTATE_ROW = 6;
    /**
     * Mesh tile positioning : part tiles same on left/right or top/bottom
     */
    public static readonly CENTER = 0;
    /**
     * Mesh tile positioning : part tiles on left
     */
    public static readonly LEFT = 1;
    /**
     * Mesh tile positioning : part tiles on right
     */
    public static readonly RIGHT = 2;
    /**
     * Mesh tile positioning : part tiles on top
     */
    public static readonly TOP = 3;
    /**
     * Mesh tile positioning : part tiles on bottom
     */
    public static readonly BOTTOM = 4;

    /**
     * Gets the default side orientation.
     * @param orientation the orientation to value to attempt to get
     * @returns the default orientation
     * @hidden
     */
    public static _GetDefaultSideOrientation(orientation?: number): number {
        return orientation || Mesh.FRONTSIDE; // works as Mesh.FRONTSIDE is 0
    }

    // Internal data
    private _internalMeshDataInfo = new _InternalMeshDataInfo();

    public get computeBonesUsingShaders(): boolean {
        return this._internalAbstractMeshDataInfo._computeBonesUsingShaders;
    }
    public set computeBonesUsingShaders(value: boolean) {
        if (this._internalAbstractMeshDataInfo._computeBonesUsingShaders === value) {
            return;
        }

        if (value && this._internalMeshDataInfo._sourcePositions) {
            // switch from software to GPU computation: we need to reset the vertex and normal buffers that have been updated by the software process
            this.setVerticesData(VertexBuffer.PositionKind, this._internalMeshDataInfo._sourcePositions.slice(), true);
            if (this._internalMeshDataInfo._sourceNormals) {
                this.setVerticesData(VertexBuffer.NormalKind, this._internalMeshDataInfo._sourceNormals.slice(), true);
            }
        }

        this._internalAbstractMeshDataInfo._computeBonesUsingShaders = value;
        this._markSubMeshesAsAttributesDirty();
    }

    /**
     * An event triggered before rendering the mesh
     */
    public get onBeforeRenderObservable(): Observable<Mesh> {
        if (!this._internalMeshDataInfo._onBeforeRenderObservable) {
            this._internalMeshDataInfo._onBeforeRenderObservable = new Observable<Mesh>();
        }

        return this._internalMeshDataInfo._onBeforeRenderObservable;
    }

    /**
     * An event triggered before binding the mesh
     */
    public get onBeforeBindObservable(): Observable<Mesh> {
        if (!this._internalMeshDataInfo._onBeforeBindObservable) {
            this._internalMeshDataInfo._onBeforeBindObservable = new Observable<Mesh>();
        }

        return this._internalMeshDataInfo._onBeforeBindObservable;
    }

    /**
    * An event triggered after rendering the mesh
    */
    public get onAfterRenderObservable(): Observable<Mesh> {
        if (!this._internalMeshDataInfo._onAfterRenderObservable) {
            this._internalMeshDataInfo._onAfterRenderObservable = new Observable<Mesh>();
        }

        return this._internalMeshDataInfo._onAfterRenderObservable;
    }

    /**
    * An event triggered before drawing the mesh
    */
    public get onBeforeDrawObservable(): Observable<Mesh> {
        if (!this._internalMeshDataInfo._onBeforeDrawObservable) {
            this._internalMeshDataInfo._onBeforeDrawObservable = new Observable<Mesh>();
        }

        return this._internalMeshDataInfo._onBeforeDrawObservable;
    }

    private _onBeforeDrawObserver: Nullable<Observer<Mesh>>;

    /**
     * Sets a callback to call before drawing the mesh. It is recommended to use onBeforeDrawObservable instead
     */
    public set onBeforeDraw(callback: () => void) {
        if (this._onBeforeDrawObserver) {
            this.onBeforeDrawObservable.remove(this._onBeforeDrawObserver);
        }
        this._onBeforeDrawObserver = this.onBeforeDrawObservable.add(callback);
    }

    public get hasInstances(): boolean {
        return this.instances.length > 0;
    }

    public get hasThinInstances(): boolean {
        return (this._thinInstanceDataStorage.instancesCount ?? 0) > 0;
    }

    // Members

    /**
     * Gets the delay loading state of the mesh (when delay loading is turned on)
     * @see https://doc.babylonjs.com/how_to/using_the_incremental_loading_system
     */
    public delayLoadState = Constants.DELAYLOADSTATE_NONE;

    /**
     * Gets the list of instances created from this mesh
     * it is not supposed to be modified manually.
     * Note also that the order of the InstancedMesh wihin the array is not significant and might change.
     * @see https://doc.babylonjs.com/how_to/how_to_use_instances
     */
    public instances = new Array<InstancedMesh>();

    /**
     * Gets the file containing delay loading data for this mesh
     */
    public delayLoadingFile: string;

    /** @hidden */
    public _binaryInfo: any;

    /**
     * User defined function used to change how LOD level selection is done
     * @see https://doc.babylonjs.com/how_to/how_to_use_lod
     */
    public onLODLevelSelection: (distance: number, mesh: Mesh, selectedLevel: Nullable<Mesh>) => void;

    /**
     * Gets or sets the morph target manager
     * @see https://doc.babylonjs.com/how_to/how_to_use_morphtargets
     */
    public get morphTargetManager(): Nullable<MorphTargetManager> {
        return this._internalMeshDataInfo._morphTargetManager;
    }

    public set morphTargetManager(value: Nullable<MorphTargetManager>) {
        if (this._internalMeshDataInfo._morphTargetManager === value) {
            return;
        }
        this._internalMeshDataInfo._morphTargetManager = value;
        this._syncGeometryWithMorphTargetManager();
    }

    // Private
    /** @hidden */
    public _creationDataStorage: Nullable<_CreationDataStorage> = null;

    /** @hidden */
    public _geometry: Nullable<Geometry> = null;
    /** @hidden */
    public _delayInfo: Array<string>;
    /** @hidden */
    public _delayLoadingFunction: (any: any, mesh: Mesh) => void;

    /** @hidden */
    public _instanceDataStorage = new _InstanceDataStorage();

    /** @hidden */
    public _thinInstanceDataStorage = new _ThinInstanceDataStorage();

    private _effectiveMaterial: Nullable<Material> = null;

    /** @hidden */
    public _shouldGenerateFlatShading: boolean = false;

    // Use by builder only to know what orientation were the mesh build in.
    /** @hidden */
    public _originalBuilderSideOrientation: number = Mesh.DEFAULTSIDE;

    /**
     * Use this property to change the original side orientation defined at construction time
     */
    public overrideMaterialSideOrientation: Nullable<number> = null;

    /**
     * Gets or sets a boolean indicating whether to render ignoring the active camera's max z setting. (false by default)
     * Note this will reduce performance when set to true.
     */
    public ignoreCameraMaxZ = false;

    /**
     * Gets the source mesh (the one used to clone this one from)
     */
    public get source(): Nullable<Mesh> {
        return this._internalMeshDataInfo._source;
    }

    /**
     * Gets the list of clones of this mesh
     * The scene must have been constructed with useClonedMeshMap=true for this to work!
     * Note that useClonedMeshMap=true is the default setting
     */
    public get cloneMeshMap(): Nullable<{ [id: string]: Mesh | undefined }> {
        return this._internalMeshDataInfo.meshMap;
    }

    /**
     * Gets or sets a boolean indicating that this mesh does not use index buffer
     */
    public get isUnIndexed(): boolean {
        return this._unIndexed;
    }

    public set isUnIndexed(value: boolean) {
        if (this._unIndexed !== value) {
            this._unIndexed = value;
            this._markSubMeshesAsAttributesDirty();
        }
    }

    /** Gets the array buffer used to store the instanced buffer used for instances' world matrices */
    public get worldMatrixInstancedBuffer() {
        return this._instanceDataStorage.instancesData;
    }

    /** Gets or sets a boolean indicating that the update of the instance buffer of the world matrices is manual */
    public get manualUpdateOfWorldMatrixInstancedBuffer() {
        return this._instanceDataStorage.manualUpdate;
    }

    public set manualUpdateOfWorldMatrixInstancedBuffer(value: boolean) {
        this._instanceDataStorage.manualUpdate = value;
    }

    /**
     * @constructor
     * @param name The value used by scene.getMeshByName() to do a lookup.
     * @param scene The scene to add this mesh to.
     * @param parent The parent of this mesh, if it has one
     * @param source An optional Mesh from which geometry is shared, cloned.
     * @param doNotCloneChildren When cloning, skip cloning child meshes of source, default False.
     *                  When false, achieved by calling a clone(), also passing False.
     *                  This will make creation of children, recursive.
     * @param clonePhysicsImpostor When cloning, include cloning mesh physics impostor, default True.
     */
    constructor(name: string, scene: Nullable<Scene> = null, parent: Nullable<Node> = null, source: Nullable<Mesh> = null, doNotCloneChildren?: boolean, clonePhysicsImpostor: boolean = true) {
        super(name, scene);

        scene = this.getScene();

        if (source) {
            // Geometry
            if (source._geometry) {
                source._geometry.applyToMesh(this);
            }

            // Deep copy
            DeepCopier.DeepCopy(source, this, [
                "name", "material", "skeleton", "instances", "parent", "uniqueId", "source", "metadata", "morphTargetManager",
                "hasInstances", "source", "worldMatrixInstancedBuffer", "hasLODLevels", "geometry", "isBlocked", "areNormalsFrozen",
                "facetNb", "isFacetDataEnabled", "lightSources", "useBones", "isAnInstance", "collider", "edgesRenderer", "forward",
                "up", "right", "absolutePosition", "absoluteScaling", "absoluteRotationQuaternion", "isWorldMatrixFrozen",
                "nonUniformScaling", "behaviors", "worldMatrixFromCache", "hasThinInstances", "cloneMeshMap"
            ], ["_poseMatrix"]);

            // Source mesh
            this._internalMeshDataInfo._source = source;
            if (scene.useClonedMeshMap) {
                if (!source._internalMeshDataInfo.meshMap) {
                    source._internalMeshDataInfo.meshMap = {};
                }
                source._internalMeshDataInfo.meshMap[this.uniqueId] = this;
            }

            // Construction Params
            // Clone parameters allowing mesh to be updated in case of parametric shapes.
            this._originalBuilderSideOrientation = source._originalBuilderSideOrientation;
            this._creationDataStorage = source._creationDataStorage;

            // Animation ranges
            if (source._ranges) {
                const ranges = source._ranges;
                for (var name in ranges) {
                    if (!ranges.hasOwnProperty(name)) {
                        continue;
                    }

                    if (!ranges[name]) {
                        continue;
                    }

                    this.createAnimationRange(name, ranges[name]!.from, ranges[name]!.to);
                }
            }

            // Metadata
            if (source.metadata && source.metadata.clone) {
                this.metadata = source.metadata.clone();
            } else {
                this.metadata = source.metadata;
            }

            // Tags
            if (Tags && Tags.HasTags(source)) {
                Tags.AddTagsTo(this, Tags.GetTags(source, true));
            }

            // Enabled
            this.setEnabled(source.isEnabled());

            // Parent
            this.parent = source.parent;

            // Pivot
            this.setPivotMatrix(source.getPivotMatrix());

            this.id = name + "." + source.id;

            // Material
            this.material = source.material;
            var index: number;
            if (!doNotCloneChildren) {
                // Children
                let directDescendants = source.getDescendants(true);
                for (let index = 0; index < directDescendants.length; index++) {
                    var child = directDescendants[index];

                    if ((<any>child).clone) {
                        (<any>child).clone(name + "." + child.name, this);
                    }
                }
            }

            // Morphs
            if (source.morphTargetManager) {
                this.morphTargetManager = source.morphTargetManager;
            }

            // Physics clone
            if (scene.getPhysicsEngine) {
                var physicsEngine = scene.getPhysicsEngine();
                if (clonePhysicsImpostor && physicsEngine) {
                    var impostor = physicsEngine.getImpostorForPhysicsObject(source);
                    if (impostor) {
                        this.physicsImpostor = impostor.clone(this);
                    }
                }
            }

            // Particles
            for (index = 0; index < scene.particleSystems.length; index++) {
                var system = scene.particleSystems[index];

                if (system.emitter === source) {
                    system.clone(system.name, this);
                }
            }
            this.refreshBoundingInfo();
            this.computeWorldMatrix(true);
        }

        // Parent
        if (parent !== null) {
            this.parent = parent;
        }

        this._instanceDataStorage.hardwareInstancedRendering = this.getEngine().getCaps().instancedArrays;
    }

    // Methods
    public instantiateHierarchy(newParent: Nullable<TransformNode> = null, options?: { doNotInstantiate: boolean}, onNewNodeCreated?: (source: TransformNode, clone: TransformNode) => void): Nullable<TransformNode> {
        let instance = (this.getTotalVertices() > 0 && (!options || !options.doNotInstantiate)) ? this.createInstance("instance of " + (this.name || this.id)) :  this.clone("Clone of " +  (this.name || this.id), newParent || this.parent, true);

        if (instance) {
            instance.parent = newParent || this.parent;
            instance.position = this.position.clone();
            instance.scaling = this.scaling.clone();
            if (this.rotationQuaternion)  {
                instance.rotationQuaternion = this.rotationQuaternion.clone();
            } else {
                instance.rotation = this.rotation.clone();
            }

            if (onNewNodeCreated) {
                onNewNodeCreated(this, instance);
            }
        }

        for (var child of this.getChildTransformNodes(true)) {
            child.instantiateHierarchy(instance, options, onNewNodeCreated);
        }

        return instance;
    }

    /**
     * Gets the class name
     * @returns the string "Mesh".
     */
    public getClassName(): string {
        return "Mesh";
    }

    /** @hidden */
    public get _isMesh() {
        return true;
    }

    /**
     * Returns a description of this mesh
     * @param fullDetails define if full details about this mesh must be used
     * @returns a descriptive string representing this mesh
     */
    public toString(fullDetails?: boolean): string {
        var ret = super.toString(fullDetails);
        ret += ", n vertices: " + this.getTotalVertices();
        ret += ", parent: " + (this._waitingParentId ? this._waitingParentId : (this.parent ? this.parent.name : "NONE"));

        if (this.animations) {
            for (var i = 0; i < this.animations.length; i++) {
                ret += ", animation[0]: " + this.animations[i].toString(fullDetails);
            }
        }

        if (fullDetails) {

            if (this._geometry) {
                let ib = this.getIndices();
                let vb = this.getVerticesData(VertexBuffer.PositionKind);

                if (vb && ib) {
                    ret += ", flat shading: " + (vb.length / 3 === ib.length ? "YES" : "NO");
                }
            } else {
                ret += ", flat shading: UNKNOWN";
            }
        }
        return ret;
    }

    /** @hidden */
    public _unBindEffect() {
        super._unBindEffect();

        for (var instance of this.instances) {
            instance._unBindEffect();
        }
    }

    /**
     * Gets a boolean indicating if this mesh has LOD
     */
    public get hasLODLevels(): boolean {
        return this._internalMeshDataInfo._LODLevels.length > 0;
    }

    /**
     * Gets the list of MeshLODLevel associated with the current mesh
     * @returns an array of MeshLODLevel
     */
    public getLODLevels(): MeshLODLevel[] {
        return this._internalMeshDataInfo._LODLevels;
    }

    private _sortLODLevels(): void {
        this._internalMeshDataInfo._LODLevels.sort((a, b) => {
            if (a.distance < b.distance) {
                return 1;
            }
            if (a.distance > b.distance) {
                return -1;
            }

            return 0;
        });
    }

    /**
     * Add a mesh as LOD level triggered at the given distance.
     * @see https://doc.babylonjs.com/how_to/how_to_use_lod
     * @param distance The distance from the center of the object to show this level
     * @param mesh The mesh to be added as LOD level (can be null)
     * @return This mesh (for chaining)
     */
    public addLODLevel(distance: number, mesh: Nullable<Mesh>): Mesh {
        if (mesh && mesh._masterMesh) {
            Logger.Warn("You cannot use a mesh as LOD level twice");
            return this;
        }

        var level = new MeshLODLevel(distance, mesh);
        this._internalMeshDataInfo._LODLevels.push(level);

        if (mesh) {
            mesh._masterMesh = this;
        }

        this._sortLODLevels();

        return this;
    }

    /**
     * Returns the LOD level mesh at the passed distance or null if not found.
     * @see https://doc.babylonjs.com/how_to/how_to_use_lod
     * @param distance The distance from the center of the object to show this level
     * @returns a Mesh or `null`
     */
    public getLODLevelAtDistance(distance: number): Nullable<Mesh> {
        let internalDataInfo = this._internalMeshDataInfo;
        for (var index = 0; index < internalDataInfo._LODLevels.length; index++) {
            var level = internalDataInfo._LODLevels[index];

            if (level.distance === distance) {
                return level.mesh;
            }
        }
        return null;
    }

    /**
     * Remove a mesh from the LOD array
     * @see https://doc.babylonjs.com/how_to/how_to_use_lod
     * @param mesh defines the mesh to be removed
     * @return This mesh (for chaining)
     */
    public removeLODLevel(mesh: Mesh): Mesh {
        let internalDataInfo = this._internalMeshDataInfo;
        for (var index = 0; index < internalDataInfo._LODLevels.length; index++) {
            if (internalDataInfo._LODLevels[index].mesh === mesh) {
                internalDataInfo._LODLevels.splice(index, 1);
                if (mesh) {
                    mesh._masterMesh = null;
                }
            }
        }

        this._sortLODLevels();
        return this;
    }

    /**
     * Returns the registered LOD mesh distant from the parameter `camera` position if any, else returns the current mesh.
     * @see https://doc.babylonjs.com/how_to/how_to_use_lod
     * @param camera defines the camera to use to compute distance
     * @param boundingSphere defines a custom bounding sphere to use instead of the one from this mesh
     * @return This mesh (for chaining)
     */
    public getLOD(camera: Camera, boundingSphere?: BoundingSphere): Nullable<AbstractMesh> {
        let internalDataInfo = this._internalMeshDataInfo;
        if (!internalDataInfo._LODLevels || internalDataInfo._LODLevels.length === 0) {
            return this;
        }

        let bSphere: BoundingSphere;

        if (boundingSphere) {
            bSphere = boundingSphere;
        } else {
            let boundingInfo = this.getBoundingInfo();

            bSphere = boundingInfo.boundingSphere;
        }

        var distanceToCamera = bSphere.centerWorld.subtract(camera.globalPosition).length();

        if (internalDataInfo._LODLevels[internalDataInfo._LODLevels.length - 1].distance > distanceToCamera) {
            if (this.onLODLevelSelection) {
                this.onLODLevelSelection(distanceToCamera, this, this);
            }
            return this;
        }

        for (var index = 0; index < internalDataInfo._LODLevels.length; index++) {
            var level = internalDataInfo._LODLevels[index];

            if (level.distance < distanceToCamera) {
                if (level.mesh) {
                    if (level.mesh.delayLoadState === Constants.DELAYLOADSTATE_NOTLOADED) {
                        level.mesh._checkDelayState();
                        return this;
                    }

                    if (level.mesh.delayLoadState === Constants.DELAYLOADSTATE_LOADING) {
                        return this;
                    }

                    level.mesh._preActivate();
                    level.mesh._updateSubMeshesBoundingInfo(this.worldMatrixFromCache);
                }

                if (this.onLODLevelSelection) {
                    this.onLODLevelSelection(distanceToCamera, this, level.mesh);
                }

                return level.mesh;
            }
        }

        if (this.onLODLevelSelection) {
            this.onLODLevelSelection(distanceToCamera, this, this);
        }
        return this;
    }

    /**
     * Gets the mesh internal Geometry object
     */
    public get geometry(): Nullable<Geometry> {
        return this._geometry;
    }

    /**
     * Returns the total number of vertices within the mesh geometry or zero if the mesh has no geometry.
     * @returns the total number of vertices
     */
    public getTotalVertices(): number {
        if (this._geometry === null || this._geometry === undefined) {
            return 0;
        }
        return this._geometry.getTotalVertices();
    }

    /**
     * Returns the content of an associated vertex buffer
     * @param kind defines which buffer to read from (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @param copyWhenShared defines a boolean indicating that if the mesh geometry is shared among some other meshes, the returned array is a copy of the internal one
     * @param forceCopy defines a boolean forcing the copy of the buffer no matter what the value of copyWhenShared is
     * @returns a FloatArray or null if the mesh has no geometry or no vertex buffer for this kind.
     */
    public getVerticesData(kind: string, copyWhenShared?: boolean, forceCopy?: boolean): Nullable<FloatArray> {
        if (!this._geometry) {
            return null;
        }
        let data = this._userInstancedBuffersStorage?.vertexBuffers[kind]?.getFloatData(this._geometry.getTotalVertices(), forceCopy || (copyWhenShared && this._geometry.meshes.length !== 1));
        if (!data) {
            data = this._geometry.getVerticesData(kind, copyWhenShared, forceCopy);
        }
        return data;
    }

    /**
     * Returns the mesh VertexBuffer object from the requested `kind`
     * @param kind defines which buffer to read from (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.NormalKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @returns a FloatArray or null if the mesh has no vertex buffer for this kind.
     */
    public getVertexBuffer(kind: string): Nullable<VertexBuffer> {
        if (!this._geometry) {
            return null;
        }

        return this._userInstancedBuffersStorage?.vertexBuffers[kind] ?? this._geometry.getVertexBuffer(kind);
    }

    /**
     * Tests if a specific vertex buffer is associated with this mesh
     * @param kind defines which buffer to check (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.NormalKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @returns a boolean
     */
    public isVerticesDataPresent(kind: string): boolean {
        if (!this._geometry) {
            if (this._delayInfo) {
                return this._delayInfo.indexOf(kind) !== -1;
            }
            return false;
        }
        return this._userInstancedBuffersStorage?.vertexBuffers[kind] !== undefined || this._geometry.isVerticesDataPresent(kind);
    }

    /**
     * Returns a boolean defining if the vertex data for the requested `kind` is updatable.
     * @param kind defines which buffer to check (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @returns a boolean
     */
    public isVertexBufferUpdatable(kind: string): boolean {
        if (!this._geometry) {
            if (this._delayInfo) {
                return this._delayInfo.indexOf(kind) !== -1;
            }
            return false;
        }
        return this._userInstancedBuffersStorage?.vertexBuffers[kind]?.isUpdatable() || this._geometry.isVertexBufferUpdatable(kind);
    }

    /**
     * Returns a string which contains the list of existing `kinds` of Vertex Data associated with this mesh.
     * @param kind defines which buffer to read from (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.NormalKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @returns an array of strings
     */
    public getVerticesDataKinds(): string[] {
        if (!this._geometry) {
            var result = new Array<string>();
            if (this._delayInfo) {
                this._delayInfo.forEach(function(kind) {
                    result.push(kind);
                });
            }
            return result;
        }
        const kinds = this._geometry.getVerticesDataKinds();
        if (this._userInstancedBuffersStorage) {
            for (const kind in this._userInstancedBuffersStorage.vertexBuffers) {
                kinds.push(kind);
            }
        }
        return kinds;
    }

    /**
     * Returns a positive integer : the total number of indices in this mesh geometry.
     * @returns the numner of indices or zero if the mesh has no geometry.
     */
    public getTotalIndices(): number {
        if (!this._geometry) {
            return 0;
        }
        return this._geometry.getTotalIndices();
    }

    /**
     * Returns an array of integers or a typed array (Int32Array, Uint32Array, Uint16Array) populated with the mesh indices.
     * @param copyWhenShared If true (default false) and and if the mesh geometry is shared among some other meshes, the returned array is a copy of the internal one.
     * @param forceCopy defines a boolean indicating that the returned array must be cloned upon returning it
     * @returns the indices array or an empty array if the mesh has no geometry
     */
    public getIndices(copyWhenShared?: boolean, forceCopy?: boolean): Nullable<IndicesArray> {

        if (!this._geometry) {
            return [];
        }
        return this._geometry.getIndices(copyWhenShared, forceCopy);
    }

    public get isBlocked(): boolean {
        return this._masterMesh !== null && this._masterMesh !== undefined;
    }

    /**
     * Determine if the current mesh is ready to be rendered
     * @param completeCheck defines if a complete check (including materials and lights) has to be done (false by default)
     * @param forceInstanceSupport will check if the mesh will be ready when used with instances (false by default)
     * @returns true if all associated assets are ready (material, textures, shaders)
     */
    public isReady(completeCheck = false, forceInstanceSupport = false): boolean {
        if (this.delayLoadState === Constants.DELAYLOADSTATE_LOADING) {
            return false;
        }

        if (!super.isReady(completeCheck)) {
            return false;
        }

        if (!this.subMeshes || this.subMeshes.length === 0) {
            return true;
        }

        if (!completeCheck) {
            return true;
        }

        let engine = this.getEngine();
        let scene = this.getScene();
        let hardwareInstancedRendering = forceInstanceSupport || engine.getCaps().instancedArrays && (this.instances.length > 0 || this.hasThinInstances);

        this.computeWorldMatrix();

        let mat = this.material || scene.defaultMaterial;
        if (mat) {
            if (mat._storeEffectOnSubMeshes) {
                for (var subMesh of this.subMeshes) {
                    let effectiveMaterial = subMesh.getMaterial();
                    if (effectiveMaterial) {
                        if (effectiveMaterial._storeEffectOnSubMeshes) {
                            if (!effectiveMaterial.isReadyForSubMesh(this, subMesh, hardwareInstancedRendering)) {
                                return false;
                            }
                        }
                        else {
                            if (!effectiveMaterial.isReady(this, hardwareInstancedRendering)) {
                                return false;
                            }
                        }
                    }
                }
            } else {
                if (!mat.isReady(this, hardwareInstancedRendering)) {
                    return false;
                }
            }
        }

        // Shadows
        for (var light of this.lightSources) {
            let generator = light.getShadowGenerator();

            if (generator && (!generator.getShadowMap()?.renderList || generator.getShadowMap()?.renderList && generator.getShadowMap()?.renderList?.indexOf(this) !== -1)) {
                for (var subMesh of this.subMeshes) {
                    if (!generator.isReady(subMesh, hardwareInstancedRendering, subMesh.getMaterial()?.needAlphaBlendingForMesh(this) ?? false)) {
                        return false;
                    }
                }
            }
        }

        // LOD
        for (var lod of this._internalMeshDataInfo._LODLevels) {
            if (lod.mesh && !lod.mesh.isReady(hardwareInstancedRendering)) {
                return false;
            }
        }

        return true;
    }

    /**
     * Gets a boolean indicating if the normals aren't to be recomputed on next mesh `positions` array update. This property is pertinent only for updatable parametric shapes.
     */
    public get areNormalsFrozen(): boolean {
        return this._internalMeshDataInfo._areNormalsFrozen;
    }

    /**
     * This function affects parametric shapes on vertex position update only : ribbons, tubes, etc. It has no effect at all on other shapes. It prevents the mesh normals from being recomputed on next `positions` array update.
     * @returns the current mesh
     */
    public freezeNormals(): Mesh {
        this._internalMeshDataInfo._areNormalsFrozen = true;
        return this;
    }

    /**
     * This function affects parametric shapes on vertex position update only : ribbons, tubes, etc. It has no effect at all on other shapes. It reactivates the mesh normals computation if it was previously frozen
     * @returns the current mesh
     */
    public unfreezeNormals(): Mesh {
        this._internalMeshDataInfo._areNormalsFrozen = false;
        return this;
    }

    /**
     * Sets a value overriding the instance count. Only applicable when custom instanced InterleavedVertexBuffer are used rather than InstancedMeshs
     */
    public set overridenInstanceCount(count: number) {
        this._instanceDataStorage.overridenInstanceCount = count;
    }

    // Methods
    /** @hidden */
    public _preActivate(): Mesh {
        let internalDataInfo = this._internalMeshDataInfo;
        var sceneRenderId = this.getScene().getRenderId();
        if (internalDataInfo._preActivateId === sceneRenderId) {
            return this;
        }

        internalDataInfo._preActivateId = sceneRenderId;
        this._instanceDataStorage.visibleInstances = null;
        return this;
    }

    /** @hidden */
    public _preActivateForIntermediateRendering(renderId: number): Mesh {
        if (this._instanceDataStorage.visibleInstances) {
            this._instanceDataStorage.visibleInstances.intermediateDefaultRenderId = renderId;
        }
        return this;
    }

    /** @hidden */
    public _registerInstanceForRenderId(instance: InstancedMesh, renderId: number): Mesh {
        if (!this._instanceDataStorage.visibleInstances) {
            this._instanceDataStorage.visibleInstances = {
                defaultRenderId: renderId,
                selfDefaultRenderId: this._renderId
            };
        }

        if (!this._instanceDataStorage.visibleInstances[renderId]) {
            if (this._instanceDataStorage.previousRenderId !== undefined && this._instanceDataStorage.isFrozen) {
                this._instanceDataStorage.visibleInstances[this._instanceDataStorage.previousRenderId] = null;
            }
            this._instanceDataStorage.previousRenderId = renderId;
            this._instanceDataStorage.visibleInstances[renderId] = new Array<InstancedMesh>();
        }

        this._instanceDataStorage.visibleInstances[renderId].push(instance);
        return this;
    }

    protected _afterComputeWorldMatrix(): void {
        super._afterComputeWorldMatrix();

        if (!this.hasThinInstances) {
            return;
        }

        if (!this.doNotSyncBoundingInfo) {
            this.thinInstanceRefreshBoundingInfo(false);
        }
    }

    /** @hidden */
    public _postActivate(): void {
        if (this.edgesShareWithInstances && this.edgesRenderer && this.edgesRenderer.isEnabled && this._renderingGroup) {
            this._renderingGroup._edgesRenderers.pushNoDuplicate(this.edgesRenderer);
            this.edgesRenderer.customInstances.push(this.getWorldMatrix());
        }
    }

    /**
     * This method recomputes and sets a new BoundingInfo to the mesh unless it is locked.
     * This means the mesh underlying bounding box and sphere are recomputed.
     * @param applySkeleton defines whether to apply the skeleton before computing the bounding info
     * @returns the current mesh
     */
    public refreshBoundingInfo(applySkeleton: boolean = false): Mesh {
        if (this._boundingInfo && this._boundingInfo.isLocked) {
            return this;
        }

        const bias = this.geometry ? this.geometry.boundingBias : null;
        this._refreshBoundingInfo(this._getPositionData(applySkeleton), bias);
        return this;
    }

    /** @hidden */
    public _createGlobalSubMesh(force: boolean): Nullable<SubMesh> {
        var totalVertices = this.getTotalVertices();
        if (!totalVertices || !this.getIndices()) {
            return null;
        }

        // Check if we need to recreate the submeshes
        if (this.subMeshes && this.subMeshes.length > 0) {
            let ib = this.getIndices();

            if (!ib) {
                return null;
            }

            var totalIndices = ib.length;
            let needToRecreate = false;

            if (force) {
                needToRecreate = true;
            } else {
                for (var submesh of this.subMeshes) {
                    if (submesh.indexStart + submesh.indexCount > totalIndices) {
                        needToRecreate = true;
                        break;
                    }

                    if (submesh.verticesStart + submesh.verticesCount > totalVertices) {
                        needToRecreate = true;
                        break;
                    }
                }
            }

            if (!needToRecreate) {
                return this.subMeshes[0];
            }
        }

        this.releaseSubMeshes();
        return new SubMesh(0, 0, totalVertices, 0, this.getTotalIndices(), this);
    }

    /**
     * This function will subdivide the mesh into multiple submeshes
     * @param count defines the expected number of submeshes
     */
    public subdivide(count: number): void {
        if (count < 1) {
            return;
        }

        var totalIndices = this.getTotalIndices();
        var subdivisionSize = (totalIndices / count) | 0;
        var offset = 0;

        // Ensure that subdivisionSize is a multiple of 3
        while (subdivisionSize % 3 !== 0) {
            subdivisionSize++;
        }

        this.releaseSubMeshes();
        for (var index = 0; index < count; index++) {
            if (offset >= totalIndices) {
                break;
            }

            SubMesh.CreateFromIndices(0, offset, index === count - 1 ? totalIndices - offset : subdivisionSize, this);

            offset += subdivisionSize;
        }

        this.synchronizeInstances();
    }

    /**
     * Copy a FloatArray into a specific associated vertex buffer
     * @param kind defines which buffer to write to (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @param data defines the data source
     * @param updatable defines if the updated vertex buffer must be flagged as updatable
     * @param stride defines the data stride size (can be null)
     * @returns the current mesh
     */
    public setVerticesData(kind: string, data: FloatArray, updatable: boolean = false, stride?: number): AbstractMesh {
        if (!this._geometry) {
            var vertexData = new VertexData();
            vertexData.set(data, kind);

            var scene = this.getScene();

            new Geometry(Geometry.RandomId(), scene, vertexData, updatable, this);
        }
        else {
            this._geometry.setVerticesData(kind, data, updatable, stride);
        }
        return this;
    }

    /**
     * Delete a vertex buffer associated with this mesh
     * @param kind defines which buffer to delete (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     */
    public removeVerticesData(kind: string) {
        if (!this._geometry) {
            return;
        }

        this._geometry.removeVerticesData(kind);
    }

    /**
     * Flags an associated vertex buffer as updatable
     * @param kind defines which buffer to use (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @param updatable defines if the updated vertex buffer must be flagged as updatable
     */
    public markVerticesDataAsUpdatable(kind: string, updatable = true) {
        let vb = this.getVertexBuffer(kind);

        if (!vb || vb.isUpdatable() === updatable) {
            return;
        }

        this.setVerticesData(kind, (<FloatArray>this.getVerticesData(kind)), updatable);
    }

    /**
     * Sets the mesh global Vertex Buffer
     * @param buffer defines the buffer to use
     * @returns the current mesh
     */
    public setVerticesBuffer(buffer: VertexBuffer): Mesh {
        if (!this._geometry) {
            this._geometry = Geometry.CreateGeometryForMesh(this);
        }

        this._geometry.setVerticesBuffer(buffer);
        return this;
    }

    /**
     * Update a specific associated vertex buffer
     * @param kind defines which buffer to write to (positions, indices, normals, etc). Possible `kind` values :
     * - VertexBuffer.PositionKind
     * - VertexBuffer.UVKind
     * - VertexBuffer.UV2Kind
     * - VertexBuffer.UV3Kind
     * - VertexBuffer.UV4Kind
     * - VertexBuffer.UV5Kind
     * - VertexBuffer.UV6Kind
     * - VertexBuffer.ColorKind
     * - VertexBuffer.MatricesIndicesKind
     * - VertexBuffer.MatricesIndicesExtraKind
     * - VertexBuffer.MatricesWeightsKind
     * - VertexBuffer.MatricesWeightsExtraKind
     * @param data defines the data source
     * @param updateExtends defines if extends info of the mesh must be updated (can be null). This is mostly useful for "position" kind
     * @param makeItUnique defines if the geometry associated with the mesh must be cloned to make the change only for this mesh (and not all meshes associated with the same geometry)
     * @returns the current mesh
     */
    public updateVerticesData(kind: string, data: FloatArray, updateExtends?: boolean, makeItUnique?: boolean): AbstractMesh {
        if (!this._geometry) {
            return this;
        }
        if (!makeItUnique) {
            this._geometry.updateVerticesData(kind, data, updateExtends);
        }
        else {
            this.makeGeometryUnique();
            this.updateVerticesData(kind, data, updateExtends, false);
        }
        return this;
    }

    /**
     * This method updates the vertex positions of an updatable mesh according to the `positionFunction` returned values.
     * @see https://doc.babylonjs.com/how_to/how_to_dynamically_morph_a_mesh#other-shapes-updatemeshpositions
     * @param positionFunction is a simple JS function what is passed the mesh `positions` array. It doesn't need to return anything
     * @param computeNormals is a boolean (default true) to enable/disable the mesh normal recomputation after the vertex position update
     * @returns the current mesh
     */
    public updateMeshPositions(positionFunction: (data: FloatArray) => void, computeNormals: boolean = true): Mesh {
        var positions = this.getVerticesData(VertexBuffer.PositionKind);
        if (!positions) {
            return this;
        }

        positionFunction(positions);
        this.updateVerticesData(VertexBuffer.PositionKind, positions, false, false);

        if (computeNormals) {
            var indices = this.getIndices();
            var normals = this.getVerticesData(VertexBuffer.NormalKind);

            if (!normals) {
                return this;
            }

            VertexData.ComputeNormals(positions, indices, normals);
            this.updateVerticesData(VertexBuffer.NormalKind, normals, false, false);
        }
        return this;
    }

    /**
     * Creates a un-shared specific occurence of the geometry for the mesh.
     * @returns the current mesh
     */
    public makeGeometryUnique(): Mesh {
        if (!this._geometry) {
            return this;
        }

        if (this._geometry.meshes.length === 1) {
            return this;
        }

        var oldGeometry = this._geometry;
        var geometry = this._geometry.copy(Geometry.RandomId());
        oldGeometry.releaseForMesh(this, true);
        geometry.applyToMesh(this);
        return this;
    }

    /**
     * Set the index buffer of this mesh
     * @param indices defines the source data
     * @param totalVertices defines the total number of vertices referenced by this index data (can be null)
     * @param updatable defines if the updated index buffer must be flagged as updatable (default is false)
     * @returns the current mesh
     */
    public setIndices(indices: IndicesArray, totalVertices: Nullable<number> = null, updatable: boolean = false): AbstractMesh {
        if (!this._geometry) {
            var vertexData = new VertexData();
            vertexData.indices = indices;

            var scene = this.getScene();

            new Geometry(Geometry.RandomId(), scene, vertexData, updatable, this);
        }
        else {
            this._geometry.setIndices(indices, totalVertices, updatable);
        }
        return this;
    }

    /**
     * Update the current index buffer
     * @param indices defines the source data
     * @param offset defines the offset in the index buffer where to store the new data (can be null)
     * @param gpuMemoryOnly defines a boolean indicating that only the GPU memory must be updated leaving the CPU version of the indices unchanged (false by default)
     * @returns the current mesh
     */
    public updateIndices(indices: IndicesArray, offset?: number, gpuMemoryOnly = false): AbstractMesh {
        if (!this._geometry) {
            return this;
        }

        this._geometry.updateIndices(indices, offset, gpuMemoryOnly);
        return this;
    }

    /**
     * Invert the geometry to move from a right handed system to a left handed one.
     * @returns the current mesh
     */
    public toLeftHanded(): Mesh {
        if (!this._geometry) {
            return this;
        }
        this._geometry.toLeftHanded();
        return this;
    }

    /** @hidden */
    public _bind(subMesh: SubMesh, effect: Effect, fillMode: number): Mesh {
        if (!this._geometry) {
            return this;
        }

        var engine = this.getScene().getEngine();

        // Wireframe
        var indexToBind;

        if (this._unIndexed) {
            indexToBind = null;
        } else {
            switch (fillMode) {
                case Material.PointFillMode:
                    indexToBind = null;
                    break;
                case Material.WireFrameFillMode:
                    indexToBind = subMesh._getLinesIndexBuffer(<IndicesArray>this.getIndices(), engine);
                    break;
                default:
                case Material.TriangleFillMode:
                    indexToBind = this._geometry.getIndexBuffer();
                    break;
            }
        }

        // VBOs
        if (!this._userInstancedBuffersStorage) {
            this._geometry._bind(effect, indexToBind);
        } else {
            this._geometry._bind(effect, indexToBind, this._userInstancedBuffersStorage.vertexBuffers, this._userInstancedBuffersStorage.vertexArrayObjects);
        }
        return this;
    }

    /** @hidden */
    public _draw(subMesh: SubMesh, fillMode: number, instancesCount?: number): Mesh {
        if (!this._geometry || !this._geometry.getVertexBuffers() || (!this._unIndexed && !this._geometry.getIndexBuffer())) {
            return this;
        }

        if (this._internalMeshDataInfo._onBeforeDrawObservable) {
            this._internalMeshDataInfo._onBeforeDrawObservable.notifyObservers(this);
        }

        let scene = this.getScene();
        let engine = scene.getEngine();

        if (this._unIndexed || fillMode == Material.PointFillMode) {
            // or triangles as points
            engine.drawArraysType(fillMode, subMesh.verticesStart, subMesh.verticesCount, instancesCount);
        } else if (fillMode == Material.WireFrameFillMode) {
            // Triangles as wireframe
            engine.drawElementsType(fillMode, 0, subMesh._linesIndexCount, instancesCount);
        } else {
            engine.drawElementsType(fillMode, subMesh.indexStart, subMesh.indexCount, instancesCount);
        }

        return this;
    }

    /**
     * Registers for this mesh a javascript function called just before the rendering process
     * @param func defines the function to call before rendering this mesh
     * @returns the current mesh
     */
    public registerBeforeRender(func: (mesh: AbstractMesh) => void): Mesh {
        this.onBeforeRenderObservable.add(func);
        return this;
    }

    /**
     * Disposes a previously registered javascript function called before the rendering
     * @param func defines the function to remove
     * @returns the current mesh
     */
    public unregisterBeforeRender(func: (mesh: AbstractMesh) => void): Mesh {
        this.onBeforeRenderObservable.removeCallback(func);
        return this;
    }

    /**
     * Registers for this mesh a javascript function called just after the rendering is complete
     * @param func defines the function to call after rendering this mesh
     * @returns the current mesh
     */
    public registerAfterRender(func: (mesh: AbstractMesh) => void): Mesh {
        this.onAfterRenderObservable.add(func);
        return this;
    }

    /**
     * Disposes a previously registered javascript function called after the rendering.
     * @param func defines the function to remove
     * @returns the current mesh
     */
    public unregisterAfterRender(func: (mesh: AbstractMesh) => void): Mesh {
        this.onAfterRenderObservable.removeCallback(func);
        return this;
    }

    /** @hidden */
    public _getInstancesRenderList(subMeshId: number, isReplacementMode: boolean = false): _InstancesBatch {
        if (this._instanceDataStorage.isFrozen && this._instanceDataStorage.previousBatch) {
            return this._instanceDataStorage.previousBatch;
        }
        var scene = this.getScene();
        const isInIntermediateRendering = scene._isInIntermediateRendering();
        const onlyForInstances = isInIntermediateRendering ? this._internalAbstractMeshDataInfo._onlyForInstancesIntermediate : this._internalAbstractMeshDataInfo._onlyForInstances;
        let batchCache = this._instanceDataStorage.batchCache;
        batchCache.mustReturn = false;
        batchCache.renderSelf[subMeshId] = isReplacementMode || (!onlyForInstances && this.isEnabled() && this.isVisible);
        batchCache.visibleInstances[subMeshId] = null;

        if (this._instanceDataStorage.visibleInstances && !isReplacementMode) {
            let visibleInstances = this._instanceDataStorage.visibleInstances;
            var currentRenderId = scene.getRenderId();
            var defaultRenderId = (isInIntermediateRendering ? visibleInstances.intermediateDefaultRenderId : visibleInstances.defaultRenderId);
            batchCache.visibleInstances[subMeshId] = visibleInstances[currentRenderId];

            if (!batchCache.visibleInstances[subMeshId] && defaultRenderId) {
                batchCache.visibleInstances[subMeshId] = visibleInstances[defaultRenderId];
            }
        }
        batchCache.hardwareInstancedRendering[subMeshId] =
                        !isReplacementMode &&
                        this._instanceDataStorage.hardwareInstancedRendering
                        && (batchCache.visibleInstances[subMeshId] !== null)
                        && (batchCache.visibleInstances[subMeshId] !== undefined);
        this._instanceDataStorage.previousBatch = batchCache;
        return batchCache;
    }

    /** @hidden */
    public _renderWithInstances(subMesh: SubMesh, fillMode: number, batch: _InstancesBatch, effect: Effect, engine: Engine): Mesh {
        var visibleInstances = batch.visibleInstances[subMesh._id];
        if (!visibleInstances) {
            return this;
        }

        let instanceStorage = this._instanceDataStorage;
        var currentInstancesBufferSize = instanceStorage.instancesBufferSize;
        var instancesBuffer = instanceStorage.instancesBuffer;
        var matricesCount = visibleInstances.length + 1;
        var bufferSize = matricesCount * 16 * 4;

        while (instanceStorage.instancesBufferSize < bufferSize) {
            instanceStorage.instancesBufferSize *= 2;
        }

        if (!instanceStorage.instancesData || currentInstancesBufferSize != instanceStorage.instancesBufferSize) {
            instanceStorage.instancesData = new Float32Array(instanceStorage.instancesBufferSize / 4);
        }

        var offset = 0;
        var instancesCount = 0;

        let renderSelf = batch.renderSelf[subMesh._id];

        const needUpdateBuffer =  !instancesBuffer || currentInstancesBufferSize !== instanceStorage.instancesBufferSize;

        if (!this._instanceDataStorage.manualUpdate && (!instanceStorage.isFrozen || needUpdateBuffer)) {
            var world = this._effectiveMesh.getWorldMatrix();
            if (renderSelf) {
                world.copyToArray(instanceStorage.instancesData, offset);
                offset += 16;
                instancesCount++;
            }

            if (visibleInstances) {
                for (var instanceIndex = 0; instanceIndex < visibleInstances.length; instanceIndex++) {
                    var instance = visibleInstances[instanceIndex];
                    instance.getWorldMatrix().copyToArray(instanceStorage.instancesData, offset);
                    offset += 16;
                    instancesCount++;
                }
            }
        } else {
            instancesCount = (renderSelf ? 1 : 0) + visibleInstances.length;
        }

        if (needUpdateBuffer) {
            if (instancesBuffer) {
                instancesBuffer.dispose();
            }

            instancesBuffer = new Buffer(engine, instanceStorage.instancesData, true, 16, false, true);
            instanceStorage.instancesBuffer = instancesBuffer;
            if (!this._userInstancedBuffersStorage) {
                this._userInstancedBuffersStorage = {
                    data: {},
                    vertexBuffers: {},
                    strides: {},
                    sizes: {},
                    vertexArrayObjects: (this.getEngine().getCaps().vertexArrayObject) ? {} : undefined
                };
            }

            this._userInstancedBuffersStorage.vertexBuffers["world0"] = instancesBuffer.createVertexBuffer("world0", 0, 4);
            this._userInstancedBuffersStorage.vertexBuffers["world1"] = instancesBuffer.createVertexBuffer("world1", 4, 4);
            this._userInstancedBuffersStorage.vertexBuffers["world2"] = instancesBuffer.createVertexBuffer("world2", 8, 4);
            this._userInstancedBuffersStorage.vertexBuffers["world3"] = instancesBuffer.createVertexBuffer("world3", 12, 4);

            this._invalidateInstanceVertexArrayObject();
        } else {
            if (!this._instanceDataStorage.isFrozen) {
                instancesBuffer!.updateDirectly(instanceStorage.instancesData, 0, instancesCount);
            }
        }

        this._processInstancedBuffers(visibleInstances, renderSelf);

        // Stats
        this.getScene()._activeIndices.addCount(subMesh.indexCount * instancesCount, false);

        // Draw
        this._bind(subMesh, effect, fillMode);
        this._draw(subMesh, fillMode, instancesCount);

        engine.unbindInstanceAttributes();
        return this;
    }

    /** @hidden */
    public _renderWithThinInstances(subMesh: SubMesh, fillMode: number, effect: Effect, engine: Engine) {
        // Stats
        const instancesCount = this._thinInstanceDataStorage?.instancesCount ?? 0;

        this.getScene()._activeIndices.addCount(subMesh.indexCount * instancesCount, false);

        // Draw
        this._bind(subMesh, effect, fillMode);
        this._draw(subMesh, fillMode, instancesCount);

        engine.unbindInstanceAttributes();
    }

    /** @hidden */
    public _processInstancedBuffers(visibleInstances: InstancedMesh[], renderSelf: boolean) {
        // Do nothing
    }

    /** @hidden */
    public _processRendering(renderingMesh: AbstractMesh, subMesh: SubMesh, effect: Effect, fillMode: number, batch: _InstancesBatch, hardwareInstancedRendering: boolean,
        onBeforeDraw: (isInstance: boolean, world: Matrix, effectiveMaterial?: Material) => void, effectiveMaterial?: Material): Mesh {
        var scene = this.getScene();
        var engine = scene.getEngine();

        if (hardwareInstancedRendering && subMesh.getRenderingMesh().hasThinInstances) {
            this._renderWithThinInstances(subMesh, fillMode, effect, engine);
            return this;
        }

        if (hardwareInstancedRendering) {
            this._renderWithInstances(subMesh, fillMode, batch, effect, engine);
        } else {
            let instanceCount = 0;
            if (batch.renderSelf[subMesh._id]) {
                // Draw
                if (onBeforeDraw) {
                    onBeforeDraw(false, renderingMesh._effectiveMesh.getWorldMatrix(), effectiveMaterial);
                }
                instanceCount++;

                this._draw(subMesh, fillMode, this._instanceDataStorage.overridenInstanceCount);
            }

            let visibleInstancesForSubMesh = batch.visibleInstances[subMesh._id];

            if (visibleInstancesForSubMesh) {
                let visibleInstanceCount = visibleInstancesForSubMesh.length;
                instanceCount += visibleInstanceCount;

                // Stats
                for (var instanceIndex = 0; instanceIndex < visibleInstanceCount; instanceIndex++) {
                    var instance = visibleInstancesForSubMesh[instanceIndex];

                    // World
                    var world = instance.getWorldMatrix();
                    if (onBeforeDraw) {
                        onBeforeDraw(true, world, effectiveMaterial);
                    }
                    // Draw
                    this._draw(subMesh, fillMode);
                }
            }

            // Stats
            scene._activeIndices.addCount(subMesh.indexCount * instanceCount, false);
        }
        return this;
    }

    /** @hidden */
    public _rebuild(): void {
        if (this._instanceDataStorage.instancesBuffer) {
            // Dispose instance buffer to be recreated in _renderWithInstances when rendered
            this._instanceDataStorage.instancesBuffer.dispose();
            this._instanceDataStorage.instancesBuffer = null;
        }
        if (this._userInstancedBuffersStorage) {
            for (var kind in this._userInstancedBuffersStorage.vertexBuffers) {
                var buffer = this._userInstancedBuffersStorage.vertexBuffers[kind];
                if (buffer) {
                    // Dispose instance buffer to be recreated in _renderWithInstances when rendered
                    buffer.dispose();
                    this._userInstancedBuffersStorage.vertexBuffers[kind] = null;
                }
            }
            if (this._userInstancedBuffersStorage.vertexArrayObjects) {
                this._userInstancedBuffersStorage.vertexArrayObjects = {};
            }
        }
        super._rebuild();
    }

    /** @hidden */
    public _freeze() {
        if (!this.subMeshes) {
            return;
        }

        // Prepare batches
        for (var index = 0; index < this.subMeshes.length; index++) {
            this._getInstancesRenderList(index);
        }

        this._effectiveMaterial = null;
        this._instanceDataStorage.isFrozen = true;
    }

    /** @hidden */
    public _unFreeze() {
        this._instanceDataStorage.isFrozen = false;
        this._instanceDataStorage.previousBatch = null;
    }

    /**
     * Triggers the draw call for the mesh. Usually, you don't need to call this method by your own because the mesh rendering is handled by the scene rendering manager
     * @param subMesh defines the subMesh to render
     * @param enableAlphaMode defines if alpha mode can be changed
     * @param effectiveMeshReplacement defines an optional mesh used to provide info for the rendering
     * @returns the current mesh
     */
    public render(subMesh: SubMesh, enableAlphaMode: boolean, effectiveMeshReplacement?: AbstractMesh): Mesh {
        var scene = this.getScene();

        if (this._internalAbstractMeshDataInfo._isActiveIntermediate) {
            this._internalAbstractMeshDataInfo._isActiveIntermediate = false;
        } else {
            this._internalAbstractMeshDataInfo._isActive = false;
        }

        if (this._checkOcclusionQuery()) {
            return this;
        }

        // Managing instances
        var batch = this._getInstancesRenderList(subMesh._id, !!effectiveMeshReplacement);

        if (batch.mustReturn) {
            return this;
        }

        // Checking geometry state
        if (!this._geometry || !this._geometry.getVertexBuffers() || (!this._unIndexed && !this._geometry.getIndexBuffer())) {
            return this;
        }

        let oldCameraMaxZ = 0;
        if (this.ignoreCameraMaxZ && scene.activeCamera && !scene._isInIntermediateRendering()) {
            oldCameraMaxZ = scene.activeCamera.maxZ;
            scene.activeCamera.maxZ = 0;
            scene.updateTransformMatrix(true);
        }

        if (this._internalMeshDataInfo._onBeforeRenderObservable) {
            this._internalMeshDataInfo._onBeforeRenderObservable.notifyObservers(this);
        }

        var engine = scene.getEngine();
        var hardwareInstancedRendering = batch.hardwareInstancedRendering[subMesh._id] || subMesh.getRenderingMesh().hasThinInstances;
        let instanceDataStorage = this._instanceDataStorage;

        let material = subMesh.getMaterial();

        if (!material) {
            return this;
        }

        // Material
        if (!instanceDataStorage.isFrozen || !this._effectiveMaterial || this._effectiveMaterial !== material) {
            if (material._storeEffectOnSubMeshes) {
                if (!material.isReadyForSubMesh(this, subMesh, hardwareInstancedRendering)) {
                    return this;
                }
            } else if (!material.isReady(this, hardwareInstancedRendering)) {
                return this;
            }

            this._effectiveMaterial = material;
        }

        // Alpha mode
        if (enableAlphaMode) {
            engine.setAlphaMode(this._effectiveMaterial.alphaMode);
        }

        var effect: Nullable<Effect>;
        if (this._effectiveMaterial._storeEffectOnSubMeshes) {
            effect = subMesh.effect;
        } else {
            effect = this._effectiveMaterial.getEffect();
        }

        for (let step of scene._beforeRenderingMeshStage) {
            step.action(this, subMesh, batch, effect);
        }

        if (!effect) {
            return this;
        }

        const effectiveMesh = effectiveMeshReplacement || this._effectiveMesh;

        var sideOrientation: Nullable<number>;

        if (!instanceDataStorage.isFrozen &&
            (this._effectiveMaterial.backFaceCulling || this.overrideMaterialSideOrientation !== null)) {
            let mainDeterminant = effectiveMesh._getWorldMatrixDeterminant();
            sideOrientation = this.overrideMaterialSideOrientation;
            if (sideOrientation == null) {
                sideOrientation = this._effectiveMaterial.sideOrientation;
            }
            if (mainDeterminant < 0) {
                sideOrientation = (sideOrientation === Material.ClockWiseSideOrientation ? Material.CounterClockWiseSideOrientation : Material.ClockWiseSideOrientation);
            }
            instanceDataStorage.sideOrientation = sideOrientation!;
        } else {
            sideOrientation = instanceDataStorage.sideOrientation;
        }

        var reverse = this._effectiveMaterial._preBind(effect, sideOrientation);

        if (this._effectiveMaterial.forceDepthWrite) {
            engine.setDepthWrite(true);
        }

        // Bind
        var fillMode = scene.forcePointsCloud ? Material.PointFillMode : (scene.forceWireframe ? Material.WireFrameFillMode : this._effectiveMaterial.fillMode);

        if (this._internalMeshDataInfo._onBeforeBindObservable) {
            this._internalMeshDataInfo._onBeforeBindObservable.notifyObservers(this);
        }

        if (!hardwareInstancedRendering) { // Binding will be done later because we need to add more info to the VB
            this._bind(subMesh, effect, fillMode);
        }

        var world = effectiveMesh.getWorldMatrix();
        if (this._effectiveMaterial._storeEffectOnSubMeshes) {
            this._effectiveMaterial.bindForSubMesh(world, this, subMesh);
        } else {
            this._effectiveMaterial.bind(world, this);
        }

        if (!this._effectiveMaterial.backFaceCulling && this._effectiveMaterial.separateCullingPass) {
            engine.setState(true, this._effectiveMaterial.zOffset, false, !reverse);
            this._processRendering(this, subMesh, effect, fillMode, batch, hardwareInstancedRendering, this._onBeforeDraw, this._effectiveMaterial);
            engine.setState(true, this._effectiveMaterial.zOffset, false, reverse);
        }

        // Draw
        this._processRendering(this, subMesh, effect, fillMode, batch, hardwareInstancedRendering, this._onBeforeDraw, this._effectiveMaterial);

        // Unbind
        this._effectiveMaterial.unbind();

        for (let step of scene._afterRenderingMeshStage) {
            step.action(this, subMesh, batch, effect);
        }

        if (this._internalMeshDataInfo._onAfterRenderObservable) {
            this._internalMeshDataInfo._onAfterRenderObservable.notifyObservers(this);
        }

        if (this.ignoreCameraMaxZ && scene.activeCamera && !scene._isInIntermediateRendering()) {
            scene.activeCamera.maxZ = oldCameraMaxZ;
            scene.updateTransformMatrix(true);
        }

        return this;
    }

    private _onBeforeDraw(isInstance: boolean, world: Matrix, effectiveMaterial?: Material): void {
        if (isInstance && effectiveMaterial) {
            effectiveMaterial.bindOnlyWorldMatrix(world);
        }
    }

    /**
     *   Renormalize the mesh and patch it up if there are no weights
     *   Similar to normalization by adding the weights compute the reciprocal and multiply all elements, this wil ensure that everything adds to 1.
     *   However in the case of zero weights then we set just a single influence to 1.
     *   We check in the function for extra's present and if so we use the normalizeSkinWeightsWithExtras rather than the FourWeights version.
     */
    public cleanMatrixWeights(): void {

        if (this.isVerticesDataPresent(VertexBuffer.MatricesWeightsKind)) {
            if (this.isVerticesDataPresent(VertexBuffer.MatricesWeightsExtraKind)) {
                this.normalizeSkinWeightsAndExtra();
            }
            else {
                this.normalizeSkinFourWeights();
            }
        }
    }

    // faster 4 weight version.
    private normalizeSkinFourWeights(): void {

        let matricesWeights = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesWeightsKind));
        let numWeights = matricesWeights.length;

        for (var a = 0; a < numWeights; a += 4) {
            // accumulate weights
            var t = matricesWeights[a] + matricesWeights[a + 1] + matricesWeights[a + 2] + matricesWeights[a + 3];
            // check for invalid weight and just set it to 1.
            if (t === 0) { matricesWeights[a] = 1; }
            else {
                // renormalize so everything adds to 1 use reciprical
                let recip = 1 / t;
                matricesWeights[a] *= recip;
                matricesWeights[a + 1] *= recip;
                matricesWeights[a + 2] *= recip;
                matricesWeights[a + 3] *= recip;
            }

        }
        this.setVerticesData(VertexBuffer.MatricesWeightsKind, matricesWeights);
    }
    // handle special case of extra verts.  (in theory gltf can handle 12 influences)
    private normalizeSkinWeightsAndExtra(): void {

        let matricesWeightsExtra = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesWeightsExtraKind));
        let matricesWeights = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesWeightsKind));
        let numWeights = matricesWeights.length;

        for (var a = 0; a < numWeights; a += 4) {
            // accumulate weights
            var t = matricesWeights[a] + matricesWeights[a + 1] + matricesWeights[a + 2] + matricesWeights[a + 3];
            t += matricesWeightsExtra[a] + matricesWeightsExtra[a + 1] + matricesWeightsExtra[a + 2] + matricesWeightsExtra[a + 3];
            // check for invalid weight and just set it to 1.
            if (t === 0) { matricesWeights[a] = 1; }
            else {
                // renormalize so everything adds to 1 use reciprical
                let recip = 1 / t;
                matricesWeights[a] *= recip;
                matricesWeights[a + 1] *= recip;
                matricesWeights[a + 2] *= recip;
                matricesWeights[a + 3] *= recip;
                // same goes for extras
                matricesWeightsExtra[a] *= recip;
                matricesWeightsExtra[a + 1] *= recip;
                matricesWeightsExtra[a + 2] *= recip;
                matricesWeightsExtra[a + 3] *= recip;
            }

        }
        this.setVerticesData(VertexBuffer.MatricesWeightsKind, matricesWeights);
        this.setVerticesData(VertexBuffer.MatricesWeightsKind, matricesWeightsExtra);
    }

    /**
     * ValidateSkinning is used to determine that a mesh has valid skinning data along with skin metrics, if missing weights,
     * or not normalized it is returned as invalid mesh the string can be used for console logs, or on screen messages to let
     * the user know there was an issue with importing the mesh
     * @returns a validation object with skinned, valid and report string
     */
    public validateSkinning(): { skinned: boolean, valid: boolean, report: string } {

        let matricesWeightsExtra = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesWeightsExtraKind));
        let matricesWeights = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesWeightsKind));
        if (matricesWeights === null || this.skeleton == null) {
            return { skinned: false, valid: true, report: "not skinned" };
        }

        let numWeights = matricesWeights.length;
        let numberNotSorted: number = 0;
        let missingWeights: number = 0;
        let maxUsedWeights: number = 0;
        let numberNotNormalized: number = 0;
        let numInfluences: number = matricesWeightsExtra === null ? 4 : 8;
        var usedWeightCounts = new Array<number>();
        for (var a = 0; a <= numInfluences; a++) {
            usedWeightCounts[a] = 0;
        }
        const toleranceEpsilon: number = 0.001;

        for (var a = 0; a < numWeights; a += 4) {

            let lastWeight: number = matricesWeights[a];
            var t = lastWeight;
            let usedWeights: number = t === 0 ? 0 : 1;

            for (var b = 1; b < numInfluences; b++) {
                var d = b < 4 ? matricesWeights[a + b] : matricesWeightsExtra[a + b - 4];
                if (d > lastWeight) { numberNotSorted++; }
                if (d !== 0) { usedWeights++; }
                t += d;
                lastWeight = d;
            }
            // count the buffer weights usage
            usedWeightCounts[usedWeights]++;

            // max influences
            if (usedWeights > maxUsedWeights) { maxUsedWeights = usedWeights; }

            // check for invalid weight and just set it to 1.
            if (t === 0) {
                missingWeights++;
            }
            else {
                // renormalize so everything adds to 1 use reciprical
                let recip = 1 / t;
                let tolerance = 0;
                for (b = 0; b < numInfluences; b++) {
                    if (b < 4) {
                        tolerance += Math.abs(matricesWeights[a + b] - (matricesWeights[a + b] * recip));
                    }
                    else {
                        tolerance += Math.abs(matricesWeightsExtra[a + b - 4] - (matricesWeightsExtra[a + b - 4] * recip));
                    }
                }
                // arbitary epsilon value for dicdating not normalized
                if (tolerance > toleranceEpsilon) { numberNotNormalized++; }
            }
        }

        // validate bone indices are in range of the skeleton
        let numBones: number = this.skeleton.bones.length;
        let matricesIndices = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesIndicesKind));
        let matricesIndicesExtra = (<FloatArray>this.getVerticesData(VertexBuffer.MatricesIndicesExtraKind));
        let numBadBoneIndices: number = 0;
        for (var a = 0; a < numWeights; a += 4) {
            for (var b = 0; b < numInfluences; b++) {
                let index = b < 4 ? matricesIndices[a + b] : matricesIndicesExtra[a + b - 4];
                if (index >= numBones || index < 0) { numBadBoneIndices++; }
            }
        }

        // log mesh stats
        var output = "Number of Weights = " + numWeights / 4 + "\nMaximum influences = " + maxUsedWeights +
            "\nMissing Weights = " + missingWeights + "\nNot Sorted = " + numberNotSorted +
            "\nNot Normalized = " + numberNotNormalized + "\nWeightCounts = [" + usedWeightCounts + "]" +
            "\nNumber of bones = " + numBones + "\nBad Bone Indices = " + numBadBoneIndices;

        return { skinned: true, valid: missingWeights === 0 && numberNotNormalized === 0 && numBadBoneIndices === 0, report: output };
    }

    /** @hidden */
    public _checkDelayState(): Mesh {
        var scene = this.getScene();
        if (this._geometry) {
            this._geometry.load(scene);
        }
        else if (this.delayLoadState === Constants.DELAYLOADSTATE_NOTLOADED) {
            this.delayLoadState = Constants.DELAYLOADSTATE_LOADING;

            this._queueLoad(scene);
        }
        return this;
    }

    private _queueLoad(scene: Scene): Mesh {
        scene._addPendingData(this);

        var getBinaryData = (this.delayLoadingFile.indexOf(".babylonbinarymeshdata") !== -1);

        Tools.LoadFile(this.delayLoadingFile, (data) => {

            if (data instanceof ArrayBuffer) {
                this._delayLoadingFunction(data, this);
            }
            else {
                this._delayLoadingFunction(JSON.parse(data), this);
            }

            this.instances.forEach((instance) => {
                instance.refreshBoundingInfo();
                instance._syncSubMeshes();
            });

            this.delayLoadState = Constants.DELAYLOADSTATE_LOADED;
            scene._removePendingData(this);

        }, () => { }, scene.offlineProvider, getBinaryData);
        return this;
    }

    /**
     * Returns `true` if the mesh is within the frustum defined by the passed array of planes.
     * A mesh is in the frustum if its bounding box intersects the frustum
     * @param frustumPlanes defines the frustum to test
     * @returns true if the mesh is in the frustum planes
     */
    public isInFrustum(frustumPlanes: Plane[]): boolean {
        if (this.delayLoadState === Constants.DELAYLOADSTATE_LOADING) {
            return false;
        }

        if (!super.isInFrustum(frustumPlanes)) {
            return false;
        }

        this._checkDelayState();

        return true;
    }

    /**
     * Sets the mesh material by the material or multiMaterial `id` property
     * @param id is a string identifying the material or the multiMaterial
     * @returns the current mesh
     */
    public setMaterialByID(id: string): Mesh {
        var materials = this.getScene().materials;
        var index: number;
        for (index = materials.length - 1; index > -1; index--) {
            if (materials[index].id === id) {
                this.material = materials[index];
                return this;
            }
        }

        // Multi
        var multiMaterials = this.getScene().multiMaterials;
        for (index = multiMaterials.length - 1; index > -1; index--) {
            if (multiMaterials[index].id === id) {
                this.material = multiMaterials[index];
                return this;
            }
        }
        return this;
    }

    /**
     * Returns as a new array populated with the mesh material and/or skeleton, if any.
     * @returns an array of IAnimatable
     */
    public getAnimatables(): IAnimatable[] {
        var results = new Array<IAnimatable>();

        if (this.material) {
            results.push(this.material);
        }

        if (this.skeleton) {
            results.push(this.skeleton);
        }

        return results;
    }

    /**
     * Modifies the mesh geometry according to the passed transformation matrix.
     * This method returns nothing but it really modifies the mesh even if it's originally not set as updatable.
     * The mesh normals are modified using the same transformation.
     * Note that, under the hood, this method sets a new VertexBuffer each call.
     * @param transform defines the transform matrix to use
     * @see https://doc.babylonjs.com/resources/baking_transformations
     * @returns the current mesh
     */
    public bakeTransformIntoVertices(transform: Matrix): Mesh {
        // Position
        if (!this.isVerticesDataPresent(VertexBuffer.PositionKind)) {
            return this;
        }

        var submeshes = this.subMeshes.splice(0);

        this._resetPointsArrayCache();

        var data = <FloatArray>this.getVerticesData(VertexBuffer.PositionKind);

        var temp = new Array<number>();
        var index: number;
        for (index = 0; index < data.length; index += 3) {
            Vector3.TransformCoordinates(Vector3.FromArray(data, index), transform).toArray(temp, index);
        }

        this.setVerticesData(VertexBuffer.PositionKind, temp, (<VertexBuffer>this.getVertexBuffer(VertexBuffer.PositionKind)).isUpdatable());

        // Normals
        if (this.isVerticesDataPresent(VertexBuffer.NormalKind)) {
            data = <FloatArray>this.getVerticesData(VertexBuffer.NormalKind);
            temp = [];
            for (index = 0; index < data.length; index += 3) {
                Vector3.TransformNormal(Vector3.FromArray(data, index), transform).normalize().toArray(temp, index);
            }
            this.setVerticesData(VertexBuffer.NormalKind, temp, (<VertexBuffer>this.getVertexBuffer(VertexBuffer.NormalKind)).isUpdatable());
        }

        // flip faces?
        if (transform.m[0] * transform.m[5] * transform.m[10] < 0) { this.flipFaces(); }

        // Restore submeshes
        this.releaseSubMeshes();
        this.subMeshes = submeshes;
        return this;
    }

    /**
     * Modifies the mesh geometry according to its own current World Matrix.
     * The mesh World Matrix is then reset.
     * This method returns nothing but really modifies the mesh even if it's originally not set as updatable.
     * Note that, under the hood, this method sets a new VertexBuffer each call.
     * @see https://doc.babylonjs.com/resources/baking_transformations
     * @param bakeIndependenlyOfChildren indicates whether to preserve all child nodes' World Matrix during baking
     * @returns the current mesh
     */
    public bakeCurrentTransformIntoVertices(bakeIndependenlyOfChildren : boolean = true): Mesh {
        this.bakeTransformIntoVertices(this.computeWorldMatrix(true));
        this.resetLocalMatrix(bakeIndependenlyOfChildren);
        return this;
    }

    // Cache

    /** @hidden */
    public get _positions(): Nullable<Vector3[]> {
        if (this._geometry) {
            return this._geometry._positions;
        }
        return null;
    }

    /** @hidden */
    public _resetPointsArrayCache(): Mesh {
        if (this._geometry) {
            this._geometry._resetPointsArrayCache();
        }
        return this;
    }

    /** @hidden */
    public _generatePointsArray(): boolean {
        if (this._geometry) {
            return this._geometry._generatePointsArray();
        }
        return false;
    }

    /**
     * Returns a new Mesh object generated from the current mesh properties.
     * This method must not get confused with createInstance()
     * @param name is a string, the name given to the new mesh
     * @param newParent can be any Node object (default `null`)
     * @param doNotCloneChildren allows/denies the recursive cloning of the original mesh children if any (default `false`)
     * @param clonePhysicsImpostor allows/denies the cloning in the same time of the original mesh `body` used by the physics engine, if any (default `true`)
     * @returns a new mesh
     */
    public clone(name: string = "", newParent: Nullable<Node> = null, doNotCloneChildren?: boolean, clonePhysicsImpostor: boolean = true): Mesh {
        return new Mesh(name, this.getScene(), newParent, this, doNotCloneChildren, clonePhysicsImpostor);
    }

    /**
     * Releases resources associated with this mesh.
     * @param doNotRecurse Set to true to not recurse into each children (recurse into each children by default)
     * @param disposeMaterialAndTextures Set to true to also dispose referenced materials and textures (false by default)
     */
    public dispose(doNotRecurse?: boolean, disposeMaterialAndTextures = false): void {
        this.morphTargetManager = null;

        if (this._geometry) {
            this._geometry.releaseForMesh(this, true);
        }

        let internalDataInfo = this._internalMeshDataInfo;

        if (internalDataInfo._onBeforeDrawObservable) {
            internalDataInfo._onBeforeDrawObservable.clear();
        }

        if (internalDataInfo._onBeforeBindObservable) {
            internalDataInfo._onBeforeBindObservable.clear();
        }

        if (internalDataInfo._onBeforeRenderObservable) {
            internalDataInfo._onBeforeRenderObservable.clear();
        }

        if (internalDataInfo._onAfterRenderObservable) {
            internalDataInfo._onAfterRenderObservable.clear();
        }

        // Sources
        if (this._scene.useClonedMeshMap) {
            if (internalDataInfo.meshMap) {
                for (const uniqueId in internalDataInfo.meshMap) {
                    const mesh = internalDataInfo.meshMap[uniqueId];
                    if (mesh) {
                        mesh._internalMeshDataInfo._source = null;
                        internalDataInfo.meshMap[uniqueId] = undefined;
                    }
                }
            }

            if (internalDataInfo._source && internalDataInfo._source._internalMeshDataInfo.meshMap) {
                internalDataInfo._source._internalMeshDataInfo.meshMap[this.uniqueId] = undefined;
            }
        }
        else {
            var meshes = this.getScene().meshes;
            for (const abstractMesh of meshes) {
                let mesh = abstractMesh as Mesh;
                if (mesh._internalMeshDataInfo && mesh._internalMeshDataInfo._source && mesh._internalMeshDataInfo._source === this) {
                    mesh._internalMeshDataInfo._source = null;
                }
            }
        }

        internalDataInfo._source = null;

        // Instances
        this._disposeInstanceSpecificData();

        // Thin instances
        this._disposeThinInstanceSpecificData();

        super.dispose(doNotRecurse, disposeMaterialAndTextures);
    }

    /** @hidden */
    public _disposeInstanceSpecificData() {
        // Do nothing
    }

    /** @hidden */
    public _disposeThinInstanceSpecificData() {
        // Do nothing
    }

    /** @hidden */
    public _invalidateInstanceVertexArrayObject() {
        // Do nothing
    }

    /**
     * Modifies the mesh geometry according to a displacement map.
     * A displacement map is a colored image. Each pixel color value (actually a gradient computed from red, green, blue values) will give the displacement to apply to each mesh vertex.
     * The mesh must be set as updatable. Its internal geometry is directly modified, no new buffer are allocated.
     * @param url is a string, the URL from the image file is to be downloaded.
     * @param minHeight is the lower limit of the displacement.
     * @param maxHeight is the upper limit of the displacement.
     * @param onSuccess is an optional Javascript function to be called just after the mesh is modified. It is passed the modified mesh and must return nothing.
     * @param uvOffset is an optional vector2 used to offset UV.
     * @param uvScale is an optional vector2 used to scale UV.
     * @param forceUpdate defines whether or not to force an update of the generated buffers. This is useful to apply on a deserialized model for instance.
     * @returns the Mesh.
     */
    public applyDisplacementMap(url: string, minHeight: number, maxHeight: number, onSuccess?: (mesh: Mesh) => void, uvOffset?: Vector2, uvScale?: Vector2, forceUpdate = false): Mesh {
        var scene = this.getScene();

        var onload = (img: HTMLImageElement | ImageBitmap) => {
            // Getting height map data
            var heightMapWidth = img.width;
            var heightMapHeight = img.height;
            var canvas = CanvasGenerator.CreateCanvas(heightMapWidth, heightMapHeight);
            var context = <CanvasRenderingContext2D>canvas.getContext("2d");

            context.drawImage(img, 0, 0);

            // Create VertexData from map data
            //Cast is due to wrong definition in lib.d.ts from ts 1.3 - https://github.com/Microsoft/TypeScript/issues/949
            var buffer = <Uint8Array>(<any>context.getImageData(0, 0, heightMapWidth, heightMapHeight).data);

            this.applyDisplacementMapFromBuffer(buffer, heightMapWidth, heightMapHeight, minHeight, maxHeight, uvOffset, uvScale, forceUpdate);
            //execute success callback, if set
            if (onSuccess) {
                onSuccess(this);
            }
        };

        Tools.LoadImage(url, onload, () => { }, scene.offlineProvider);
        return this;
    }

    /**
     * Modifies the mesh geometry according to a displacementMap buffer.
     * A displacement map is a colored image. Each pixel color value (actually a gradient computed from red, green, blue values) will give the displacement to apply to each mesh vertex.
     * The mesh must be set as updatable. Its internal geometry is directly modified, no new buffer are allocated.
     * @param buffer is a `Uint8Array` buffer containing series of `Uint8` lower than 255, the red, green, blue and alpha values of each successive pixel.
     * @param heightMapWidth is the width of the buffer image.
     * @param heightMapHeight is the height of the buffer image.
     * @param minHeight is the lower limit of the displacement.
     * @param maxHeight is the upper limit of the displacement.
     * @param onSuccess is an optional Javascript function to be called just after the mesh is modified. It is passed the modified mesh and must return nothing.
     * @param uvOffset is an optional vector2 used to offset UV.
     * @param uvScale is an optional vector2 used to scale UV.
     * @param forceUpdate defines whether or not to force an update of the generated buffers. This is useful to apply on a deserialized model for instance.
     * @returns the Mesh.
     */
    public applyDisplacementMapFromBuffer(buffer: Uint8Array, heightMapWidth: number, heightMapHeight: number, minHeight: number, maxHeight: number, uvOffset?: Vector2, uvScale?: Vector2, forceUpdate = false): Mesh {
        if (!this.isVerticesDataPresent(VertexBuffer.PositionKind)
            || !this.isVerticesDataPresent(VertexBuffer.NormalKind)
            || !this.isVerticesDataPresent(VertexBuffer.UVKind)) {
            Logger.Warn("Cannot call applyDisplacementMap: Given mesh is not complete. Position, Normal or UV are missing");
            return this;
        }

        var positions = <FloatArray>this.getVerticesData(VertexBuffer.PositionKind, true, true);
        var normals = <FloatArray>this.getVerticesData(VertexBuffer.NormalKind);
        var uvs = <number[]>this.getVerticesData(VertexBuffer.UVKind);
        var position = Vector3.Zero();
        var normal = Vector3.Zero();
        var uv = Vector2.Zero();

        uvOffset = uvOffset || Vector2.Zero();
        uvScale = uvScale || new Vector2(1, 1);

        for (var index = 0; index < positions.length; index += 3) {
            Vector3.FromArrayToRef(positions, index, position);
            Vector3.FromArrayToRef(normals, index, normal);
            Vector2.FromArrayToRef(uvs, (index / 3) * 2, uv);

            // Compute height
            var u = ((Math.abs(uv.x * uvScale.x + uvOffset.x % 1) * (heightMapWidth - 1)) % heightMapWidth) | 0;
            var v = ((Math.abs(uv.y * uvScale.y + uvOffset.y % 1) * (heightMapHeight - 1)) % heightMapHeight) | 0;

            var pos = (u + v * heightMapWidth) * 4;
            var r = buffer[pos] / 255.0;
            var g = buffer[pos + 1] / 255.0;
            var b = buffer[pos + 2] / 255.0;

            var gradient = r * 0.3 + g * 0.59 + b * 0.11;

            normal.normalize();
            normal.scaleInPlace(minHeight + (maxHeight - minHeight) * gradient);
            position = position.add(normal);

            position.toArray(positions, index);
        }

        VertexData.ComputeNormals(positions, this.getIndices(), normals);

        if (forceUpdate) {
            this.setVerticesData(VertexBuffer.PositionKind, positions);
            this.setVerticesData(VertexBuffer.NormalKind, normals);
        }
        else {
            this.updateVerticesData(VertexBuffer.PositionKind, positions);
            this.updateVerticesData(VertexBuffer.NormalKind, normals);
        }
        return this;
    }

    /**
     * Modify the mesh to get a flat shading rendering.
     * This means each mesh facet will then have its own normals. Usually new vertices are added in the mesh geometry to get this result.
     * Warning : the mesh is really modified even if not set originally as updatable and, under the hood, a new VertexBuffer is allocated.
     * @returns current mesh
     */
    public convertToFlatShadedMesh(): Mesh {
        var kinds = this.getVerticesDataKinds();
        var vbs: { [key: string]: VertexBuffer } = {};
        var data: { [key: string]: FloatArray } = {};
        var newdata: { [key: string]: Array<number> } = {};
        var updatableNormals = false;
        var kindIndex: number;
        var kind: string;
        for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
            kind = kinds[kindIndex];
            var vertexBuffer = <VertexBuffer>this.getVertexBuffer(kind);

            if (kind === VertexBuffer.NormalKind) {
                updatableNormals = vertexBuffer.isUpdatable();
                kinds.splice(kindIndex, 1);
                kindIndex--;
                continue;
            }

            vbs[kind] = vertexBuffer;
            data[kind] = <FloatArray>vbs[kind].getData();
            newdata[kind] = [];
        }

        // Save previous submeshes
        var previousSubmeshes = this.subMeshes.slice(0);

        var indices = <IndicesArray>this.getIndices();
        var totalIndices = this.getTotalIndices();

        // Generating unique vertices per face
        var index: number;
        for (index = 0; index < totalIndices; index++) {
            var vertexIndex = indices[index];

            for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
                kind = kinds[kindIndex];
                var stride = vbs[kind].getStrideSize();

                for (var offset = 0; offset < stride; offset++) {
                    newdata[kind].push(data[kind][vertexIndex * stride + offset]);
                }
            }
        }

        // Updating faces & normal
        var normals = [];
        var positions = newdata[VertexBuffer.PositionKind];
        for (index = 0; index < totalIndices; index += 3) {
            indices[index] = index;
            indices[index + 1] = index + 1;
            indices[index + 2] = index + 2;

            var p1 = Vector3.FromArray(positions, index * 3);
            var p2 = Vector3.FromArray(positions, (index + 1) * 3);
            var p3 = Vector3.FromArray(positions, (index + 2) * 3);

            var p1p2 = p1.subtract(p2);
            var p3p2 = p3.subtract(p2);

            var normal = Vector3.Normalize(Vector3.Cross(p1p2, p3p2));

            // Store same normals for every vertex
            for (var localIndex = 0; localIndex < 3; localIndex++) {
                normals.push(normal.x);
                normals.push(normal.y);
                normals.push(normal.z);
            }
        }

        this.setIndices(indices);
        this.setVerticesData(VertexBuffer.NormalKind, normals, updatableNormals);

        // Updating vertex buffers
        for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
            kind = kinds[kindIndex];
            this.setVerticesData(kind, newdata[kind], vbs[kind].isUpdatable());
        }

        // Updating submeshes
        this.releaseSubMeshes();
        for (var submeshIndex = 0; submeshIndex < previousSubmeshes.length; submeshIndex++) {
            var previousOne = previousSubmeshes[submeshIndex];
            SubMesh.AddToMesh(previousOne.materialIndex, previousOne.indexStart, previousOne.indexCount, previousOne.indexStart, previousOne.indexCount, this);
        }

        this.synchronizeInstances();
        return this;
    }

    /**
     * This method removes all the mesh indices and add new vertices (duplication) in order to unfold facets into buffers.
     * In other words, more vertices, no more indices and a single bigger VBO.
     * The mesh is really modified even if not set originally as updatable. Under the hood, a new VertexBuffer is allocated.
     * @returns current mesh
     */
    public convertToUnIndexedMesh(): Mesh {
        var kinds = this.getVerticesDataKinds();
        var vbs: { [key: string]: VertexBuffer } = {};
        var data: { [key: string]: FloatArray } = {};
        var newdata: { [key: string]: Array<number> } = {};
        var kindIndex: number;
        var kind: string;
        for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
            kind = kinds[kindIndex];
            var vertexBuffer = <VertexBuffer>this.getVertexBuffer(kind);
            vbs[kind] = vertexBuffer;
            data[kind] = <FloatArray>vbs[kind].getData();
            newdata[kind] = [];
        }

        // Save previous submeshes
        var previousSubmeshes = this.subMeshes.slice(0);

        var indices = <IndicesArray>this.getIndices();
        var totalIndices = this.getTotalIndices();

        // Generating unique vertices per face
        var index: number;
        for (index = 0; index < totalIndices; index++) {
            var vertexIndex = indices[index];

            for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
                kind = kinds[kindIndex];
                var stride = vbs[kind].getStrideSize();

                for (var offset = 0; offset < stride; offset++) {
                    newdata[kind].push(data[kind][vertexIndex * stride + offset]);
                }
            }
        }

        // Updating indices
        for (index = 0; index < totalIndices; index += 3) {
            indices[index] = index;
            indices[index + 1] = index + 1;
            indices[index + 2] = index + 2;
        }

        this.setIndices(indices);

        // Updating vertex buffers
        for (kindIndex = 0; kindIndex < kinds.length; kindIndex++) {
            kind = kinds[kindIndex];
            this.setVerticesData(kind, newdata[kind], vbs[kind].isUpdatable());
        }

        // Updating submeshes
        this.releaseSubMeshes();
        for (var submeshIndex = 0; submeshIndex < previousSubmeshes.length; submeshIndex++) {
            var previousOne = previousSubmeshes[submeshIndex];
            SubMesh.AddToMesh(previousOne.materialIndex, previousOne.indexStart, previousOne.indexCount, previousOne.indexStart, previousOne.indexCount, this);
        }

        this._unIndexed = true;

        this.synchronizeInstances();
        return this;
    }

    /**
     * Inverses facet orientations.
     * Warning : the mesh is really modified even if not set originally as updatable. A new VertexBuffer is created under the hood each call.
     * @param flipNormals will also inverts the normals
     * @returns current mesh
     */
    public flipFaces(flipNormals: boolean = false): Mesh {
        var vertex_data = VertexData.ExtractFromMesh(this);
        var i: number;
        if (flipNormals && this.isVerticesDataPresent(VertexBuffer.NormalKind) && vertex_data.normals) {
            for (i = 0; i < vertex_data.normals.length; i++) {
                vertex_data.normals[i] *= -1;
            }
        }

        if (vertex_data.indices) {
            var temp;
            for (i = 0; i < vertex_data.indices.length; i += 3) {
                // reassign indices
                temp = vertex_data.indices[i + 1];
                vertex_data.indices[i + 1] = vertex_data.indices[i + 2];
                vertex_data.indices[i + 2] = temp;
            }
        }

        vertex_data.applyToMesh(this, this.isVertexBufferUpdatable(VertexBuffer.PositionKind));
        return this;
    }

    /**
     * Increase the number of facets and hence vertices in a mesh
     * Vertex normals are interpolated from existing vertex normals
     * Warning : the mesh is really modified even if not set originally as updatable. A new VertexBuffer is created under the hood each call.
     * @param numberPerEdge the number of new vertices to add to each edge of a facet, optional default 1
     */
    public increaseVertices(numberPerEdge: number): void {
        var vertex_data = VertexData.ExtractFromMesh(this);
        var uvs = vertex_data.uvs;
        var currentIndices = vertex_data.indices;
        var positions = vertex_data.positions;
        var normals = vertex_data.normals;

        if (!currentIndices || !positions || !normals || !uvs) {
            Logger.Warn("VertexData contains null entries");
        }
        else {
            var segments: number = numberPerEdge + 1; //segments per current facet edge, become sides of new facets
            var tempIndices: Array<Array<number>> = new Array();
            for (var i = 0; i < segments + 1; i++) {
                tempIndices[i] = new Array();
            }
            var a: number;  //vertex index of one end of a side
            var b: number; //vertex index of other end of the side
            var deltaPosition: Vector3 = new Vector3(0, 0, 0);
            var deltaNormal: Vector3 = new Vector3(0, 0, 0);
            var deltaUV: Vector2 = new Vector2(0, 0);
            var indices: number[] = new Array();
            var vertexIndex: number[] = new Array();
            var side: Array<Array<Array<number>>> = new Array();
            var len: number;
            var positionPtr: number = positions.length;
            var uvPtr: number = uvs.length;

            for (var i = 0; i < currentIndices.length; i += 3) {
                vertexIndex[0] = currentIndices[i];
                vertexIndex[1] = currentIndices[i + 1];
                vertexIndex[2] = currentIndices[i + 2];
                for (var j = 0; j < 3; j++) {
                    a = vertexIndex[j];
                    b = vertexIndex[(j + 1) % 3];
                    if (side[a] === undefined && side[b] === undefined) {
                        side[a] = new Array();
                        side[b] = new Array();
                    }
                    else {
                        if (side[a] === undefined) {
                            side[a] = new Array();
                        }
                        if (side[b] === undefined) {
                            side[b] = new Array();
                        }
                    }
                    if (side[a][b] === undefined && side[b][a] === undefined) {
                        side[a][b] = [];
                        deltaPosition.x = (positions[3 * b] - positions[3 * a]) / segments;
                        deltaPosition.y = (positions[3 * b + 1] - positions[3 * a + 1]) / segments;
                        deltaPosition.z = (positions[3 * b + 2] - positions[3 * a + 2]) / segments;
                        deltaNormal.x = (normals[3 * b] - normals[3 * a]) / segments;
                        deltaNormal.y = (normals[3 * b + 1] - normals[3 * a + 1]) / segments;
                        deltaNormal.z = (normals[3 * b + 2] - normals[3 * a + 2]) / segments;
                        deltaUV.x = (uvs[2 * b] - uvs[2 * a]) / segments;
                        deltaUV.y = (uvs[2 * b + 1] - uvs[2 * a + 1]) / segments;
                        side[a][b].push(a);
                        for (var k = 1; k < segments; k++) {
                            side[a][b].push(positions.length / 3);
                            positions[positionPtr] = positions[3 * a] + k * deltaPosition.x;
                            normals[positionPtr++] = normals[3 * a] + k * deltaNormal.x;
                            positions[positionPtr] = positions[3 * a + 1] + k * deltaPosition.y;
                            normals[positionPtr++] = normals[3 * a + 1] + k * deltaNormal.y;
                            positions[positionPtr] = positions[3 * a + 2] + k * deltaPosition.z;
                            normals[positionPtr++] = normals[3 * a + 2] + k * deltaNormal.z;
                            uvs[uvPtr++] = uvs[2 * a] + k * deltaUV.x;
                            uvs[uvPtr++] = uvs[2 * a + 1] + k * deltaUV.y;
                        }
                        side[a][b].push(b);
                        side[b][a] = new Array();
                        len = side[a][b].length;
                        for (var idx = 0; idx < len; idx++) {
                            side[b][a][idx] = side[a][b][len - 1 - idx];
                        }
                    }
                }
                //Calculate positions, normals and uvs of new internal vertices
                tempIndices[0][0] = currentIndices[i];
                tempIndices[1][0] = side[currentIndices[i]][currentIndices[i + 1]][1];
                tempIndices[1][1] = side[currentIndices[i]][currentIndices[i + 2]][1];
                for (var k = 2; k < segments; k++) {
                    tempIndices[k][0] = side[currentIndices[i]][currentIndices[i + 1]][k];
                    tempIndices[k][k] = side[currentIndices[i]][currentIndices[i + 2]][k];
                    deltaPosition.x = (positions[3 * tempIndices[k][k]] - positions[3 * tempIndices[k][0]]) / k;
                    deltaPosition.y = (positions[3 * tempIndices[k][k] + 1] - positions[3 * tempIndices[k][0] + 1]) / k;
                    deltaPosition.z = (positions[3 * tempIndices[k][k] + 2] - positions[3 * tempIndices[k][0] + 2]) / k;
                    deltaNormal.x = (normals[3 * tempIndices[k][k]] - normals[3 * tempIndices[k][0]]) / k;
                    deltaNormal.y = (normals[3 * tempIndices[k][k] + 1] - normals[3 * tempIndices[k][0] + 1]) / k;
                    deltaNormal.z = (normals[3 * tempIndices[k][k] + 2] - normals[3 * tempIndices[k][0] + 2]) / k;
                    deltaUV.x = (uvs[2 * tempIndices[k][k]] - uvs[2 * tempIndices[k][0]]) / k;
                    deltaUV.y = (uvs[2 * tempIndices[k][k] + 1] - uvs[2 * tempIndices[k][0] + 1]) / k;
                    for (var j = 1; j < k; j++) {
                        tempIndices[k][j] = positions.length / 3;
                        positions[positionPtr] = positions[3 * tempIndices[k][0]] + j * deltaPosition.x;
                        normals[positionPtr++] = normals[3 * tempIndices[k][0]] + j * deltaNormal.x;
                        positions[positionPtr] = positions[3 * tempIndices[k][0] + 1] + j * deltaPosition.y;
                        normals[positionPtr++] = normals[3 * tempIndices[k][0] + 1] + j * deltaNormal.y;
                        positions[positionPtr] = positions[3 * tempIndices[k][0] + 2] + j * deltaPosition.z;
                        normals[positionPtr++] = normals[3 * tempIndices[k][0] + 2] + j * deltaNormal.z;
                        uvs[uvPtr++] = uvs[2 * tempIndices[k][0]] + j * deltaUV.x;
                        uvs[uvPtr++] = uvs[2 * tempIndices[k][0] + 1] + j * deltaUV.y;
                    }
                }
                tempIndices[segments] = side[currentIndices[i + 1]][currentIndices[i + 2]];

                // reform indices
                indices.push(tempIndices[0][0], tempIndices[1][0], tempIndices[1][1]);
                for (var k = 1; k < segments; k++) {
                    for (var j = 0; j < k; j++) {
                        indices.push(tempIndices[k][j], tempIndices[k + 1][j], tempIndices[k + 1][j + 1]);
                        indices.push(tempIndices[k][j], tempIndices[k + 1][j + 1], tempIndices[k][j + 1]);
                    }
                    indices.push(tempIndices[k][j], tempIndices[k + 1][j], tempIndices[k + 1][j + 1]);
                }
            }

            vertex_data.indices = indices;
            vertex_data.applyToMesh(this, this.isVertexBufferUpdatable(VertexBuffer.PositionKind));
        }
    }

    /**
     * Force adjacent facets to share vertices and remove any facets that have all vertices in a line
     * This will undo any application of covertToFlatShadedMesh
     * Warning : the mesh is really modified even if not set originally as updatable. A new VertexBuffer is created under the hood each call.
     */
    public forceSharedVertices(): void {
        var vertex_data = VertexData.ExtractFromMesh(this);
        var currentUVs = vertex_data.uvs;
        var currentIndices = vertex_data.indices;
        var currentPositions = vertex_data.positions;
        var currentColors = vertex_data.colors;

        if (currentIndices === void 0 || currentPositions === void 0 || currentIndices === null || currentPositions === null) {
            Logger.Warn("VertexData contains empty entries");
        }
        else {
            var positions: Array<number> = new Array();
            var indices: Array<number> = new Array();
            var uvs: Array<number> = new Array();
            var colors: Array<number> = new Array();
            var pstring: Array<string> = new Array(); //lists facet vertex positions (a,b,c) as string "a|b|c"

            var indexPtr: number = 0; // pointer to next available index value
            var uniquePositions: { [key: string]: number } = {}; // unique vertex positions
            var ptr: number; // pointer to element in uniquePositions
            var facet: Array<number>;

            for (var i = 0; i < currentIndices.length; i += 3) {
                facet = [currentIndices[i], currentIndices[i + 1], currentIndices[i + 2]]; //facet vertex indices
                pstring = new Array();
                for (var j = 0; j < 3; j++) {
                    pstring[j] = "";
                    for (var k = 0; k < 3; k++) {
                        //small values make 0
                        if (Math.abs(currentPositions[3 * facet[j] + k]) < 0.00000001) {
                            currentPositions[3 * facet[j] + k] = 0;
                        }
                        pstring[j] += currentPositions[3 * facet[j] + k] + "|";
                    }
                }
                //check facet vertices to see that none are repeated
                // do not process any facet that has a repeated vertex, ie is a line
                if (!(pstring[0] == pstring[1] || pstring[0] == pstring[2] || pstring[1] == pstring[2])) {
                    //for each facet position check if already listed in uniquePositions
                    // if not listed add to uniquePositions and set index pointer
                    // if listed use its index in uniquePositions and new index pointer
                    for (var j = 0; j < 3; j++) {
                        ptr = uniquePositions[pstring[j]];
                        if (ptr === undefined) {
                            uniquePositions[pstring[j]] = indexPtr;
                            ptr = indexPtr++;
                            //not listed so add individual x, y, z coordinates to positions
                            for (var k = 0; k < 3; k++) {
                                positions.push(currentPositions[3 * facet[j] + k]);
                            }
                            if (currentColors !== null && currentColors !== void 0) {
                                for (var k = 0; k < 4; k++) {
                                    colors.push(currentColors[4 * facet[j] + k]);
                                }
                            }
                            if (currentUVs !== null && currentUVs !== void 0) {
                                for (var k = 0; k < 2; k++) {
                                    uvs.push(currentUVs[2 * facet[j] + k]);
                                }
                            }
                        }
                        // add new index pointer to indices array
                        indices.push(ptr);
                    }
                }
            }

            var normals: Array<number> = new Array();
            VertexData.ComputeNormals(positions, indices, normals);

            //create new vertex data object and update
            vertex_data.positions = positions;
            vertex_data.indices = indices;
            vertex_data.normals = normals;
            if (currentUVs !== null && currentUVs !== void 0) {
                vertex_data.uvs = uvs;
            }
            if (currentColors !== null && currentColors !== void 0) {
                vertex_data.colors = colors;
            }

            vertex_data.applyToMesh(this, this.isVertexBufferUpdatable(VertexBuffer.PositionKind));
        }
    }

    // Instances
    /** @hidden */
    public static _instancedMeshFactory(name: string, mesh: Mesh): InstancedMesh {
        throw _DevTools.WarnImport("InstancedMesh");
    }

    /** @hidden */
    public static _PhysicsImpostorParser(scene: Scene, physicObject: IPhysicsEnabledObject, jsonObject: any): PhysicsImpostor {
        throw _DevTools.WarnImport("PhysicsImpostor");
    }

    /**
     * Creates a new InstancedMesh object from the mesh model.
     * @see https://doc.babylonjs.com/how_to/how_to_use_instances
     * @param name defines the name of the new instance
     * @returns a new InstancedMesh
     */
    public createInstance(name: string): InstancedMesh {
        return Mesh._instancedMeshFactory(name, this);
    }

    /**
     * Synchronises all the mesh instance submeshes to the current mesh submeshes, if any.
     * After this call, all the mesh instances have the same submeshes than the current mesh.
     * @returns the current mesh
     */
    public synchronizeInstances(): Mesh {
        for (var instanceIndex = 0; instanceIndex < this.instances.length; instanceIndex++) {
            var instance = this.instances[instanceIndex];
            instance._syncSubMeshes();
        }
        return this;
    }

    /**
     * Optimization of the mesh's indices, in case a mesh has duplicated vertices.
     * The function will only reorder the indices and will not remove unused vertices to avoid problems with submeshes.
     * This should be used together with the simplification to avoid disappearing triangles.
     * @param successCallback an optional success callback to be called after the optimization finished.
     * @returns the current mesh
     */
    public optimizeIndices(successCallback?: (mesh?: Mesh) => void): Mesh {
        var indices = <IndicesArray>this.getIndices();
        var positions = this.getVerticesData(VertexBuffer.PositionKind);

        if (!positions || !indices) {
            return this;
        }

        var vectorPositions = new Array<Vector3>();
        for (var pos = 0; pos < positions.length; pos = pos + 3) {
            vectorPositions.push(Vector3.FromArray(positions, pos));
        }
        var dupes = new Array<number>();

        AsyncLoop.SyncAsyncForLoop(vectorPositions.length, 40, (iteration) => {
            var realPos = vectorPositions.length - 1 - iteration;
            var testedPosition = vectorPositions[realPos];
            for (var j = 0; j < realPos; ++j) {
                var againstPosition = vectorPositions[j];
                if (testedPosition.equals(againstPosition)) {
                    dupes[realPos] = j;
                    break;
                }
            }
        }, () => {
            for (var i = 0; i < indices.length; ++i) {
                indices[i] = dupes[indices[i]] || indices[i];
            }

            //indices are now reordered
            var originalSubMeshes = this.subMeshes.slice(0);
            this.setIndices(indices);
            this.subMeshes = originalSubMeshes;
            if (successCallback) {
                successCallback(this);
            }
        });
        return this;
    }

    /**
     * Serialize current mesh
     * @param serializationObject defines the object which will receive the serialization data
     */
    public serialize(serializationObject: any): void {
        serializationObject.name = this.name;
        serializationObject.id = this.id;
        serializationObject.uniqueId = this.uniqueId;
        serializationObject.type = this.getClassName();

        if (Tags && Tags.HasTags(this)) {
            serializationObject.tags = Tags.GetTags(this);
        }

        serializationObject.position = this.position.asArray();

        if (this.rotationQuaternion) {
            serializationObject.rotationQuaternion = this.rotationQuaternion.asArray();
        } else if (this.rotation) {
            serializationObject.rotation = this.rotation.asArray();
        }

        serializationObject.scaling = this.scaling.asArray();
        if (this._postMultiplyPivotMatrix) {
            serializationObject.pivotMatrix = this.getPivotMatrix().asArray();
        } else {
            serializationObject.localMatrix = this.getPivotMatrix().asArray();
        }

        serializationObject.isEnabled = this.isEnabled(false);
        serializationObject.isVisible = this.isVisible;
        serializationObject.infiniteDistance = this.infiniteDistance;
        serializationObject.pickable = this.isPickable;

        serializationObject.receiveShadows = this.receiveShadows;

        serializationObject.billboardMode = this.billboardMode;
        serializationObject.visibility = this.visibility;

        serializationObject.checkCollisions = this.checkCollisions;
        serializationObject.isBlocker = this.isBlocker;
        serializationObject.overrideMaterialSideOrientation = this.overrideMaterialSideOrientation;

        // Parent
        if (this.parent) {
            serializationObject.parentId = this.parent.id;
        }

        // Geometry
        serializationObject.isUnIndexed = this.isUnIndexed;
        var geometry = this._geometry;
        if (geometry && this.subMeshes) {
            var geometryId = geometry.id;
            serializationObject.geometryId = geometryId;

            // SubMeshes
            serializationObject.subMeshes = [];
            for (var subIndex = 0; subIndex < this.subMeshes.length; subIndex++) {
                var subMesh = this.subMeshes[subIndex];

                serializationObject.subMeshes.push({
                    materialIndex: subMesh.materialIndex,
                    verticesStart: subMesh.verticesStart,
                    verticesCount: subMesh.verticesCount,
                    indexStart: subMesh.indexStart,
                    indexCount: subMesh.indexCount
                });
            }
        }

        // Material
        if (this.material) {
            if (!this.material.doNotSerialize) {
                serializationObject.materialId = this.material.id;
            }
        } else {
            this.material = null;
        }

        // Morph targets
        if (this.morphTargetManager) {
            serializationObject.morphTargetManagerId = this.morphTargetManager.uniqueId;
        }

        // Skeleton
        if (this.skeleton) {
            serializationObject.skeletonId = this.skeleton.id;
            serializationObject.numBoneInfluencers = this.numBoneInfluencers;
        }

        // Physics
        //TODO implement correct serialization for physics impostors.
        if (this.getScene()._getComponent(SceneComponentConstants.NAME_PHYSICSENGINE)) {
            let impostor = this.getPhysicsImpostor();
            if (impostor) {
                serializationObject.physicsMass = impostor.getParam("mass");
                serializationObject.physicsFriction = impostor.getParam("friction");
                serializationObject.physicsRestitution = impostor.getParam("mass");
                serializationObject.physicsImpostor = impostor.type;
            }
        }

        // Metadata
        if (this.metadata) {
            serializationObject.metadata = this.metadata;
        }

        // Instances
        serializationObject.instances = [];
        for (var index = 0; index < this.instances.length; index++) {
            var instance = this.instances[index];
            if (instance.doNotSerialize) {
                continue;
            }

            var serializationInstance: any = {
                name: instance.name,
                id: instance.id,
                isEnabled: instance.isEnabled(false),
                isVisible: instance.isVisible,
                isPickable: instance.isPickable,
                checkCollisions: instance.checkCollisions,
                position: instance.position.asArray(),
                scaling: instance.scaling.asArray()
            };

            if (instance.parent) {
                serializationInstance.parentId = instance.parent.id;
            }

            if (instance.rotationQuaternion) {
                serializationInstance.rotationQuaternion = instance.rotationQuaternion.asArray();
            } else if (instance.rotation) {
                serializationInstance.rotation = instance.rotation.asArray();
            }

            // Physics
            //TODO implement correct serialization for physics impostors.
            if (this.getScene()._getComponent(SceneComponentConstants.NAME_PHYSICSENGINE)) {
                let impostor = instance.getPhysicsImpostor();
                if (impostor) {
                    serializationInstance.physicsMass = impostor.getParam("mass");
                    serializationInstance.physicsFriction = impostor.getParam("friction");
                    serializationInstance.physicsRestitution = impostor.getParam("mass");
                    serializationInstance.physicsImpostor = impostor.type;
                }
            }

            // Metadata
            if (instance.metadata) {
                serializationInstance.metadata = instance.metadata;
            }

            serializationObject.instances.push(serializationInstance);

            // Animations
            SerializationHelper.AppendSerializedAnimations(instance, serializationInstance);
            serializationInstance.ranges = instance.serializeAnimationRanges();
        }

        // Thin instances
        if (this._thinInstanceDataStorage.instancesCount && this._thinInstanceDataStorage.matrixData) {
            serializationObject.thinInstances = {
                instancesCount: this._thinInstanceDataStorage.instancesCount,
                matrixData: Tools.SliceToArray(this._thinInstanceDataStorage.matrixData),
                matrixBufferSize: this._thinInstanceDataStorage.matrixBufferSize,
            };

            if (this._userThinInstanceBuffersStorage) {
                const userThinInstance: any = {
                    data: {},
                    sizes: {},
                    strides: {},
                };

                for (const kind in this._userThinInstanceBuffersStorage.data) {
                    userThinInstance.data[kind] = Tools.SliceToArray(this._userThinInstanceBuffersStorage.data[kind]);
                    userThinInstance.sizes[kind] = this._userThinInstanceBuffersStorage.sizes[kind];
                    userThinInstance.strides[kind] = this._userThinInstanceBuffersStorage.strides[kind];
                }

                serializationObject.thinInstances.userThinInstance = userThinInstance;
            }
        }

        // Animations
        SerializationHelper.AppendSerializedAnimations(this, serializationObject);
        serializationObject.ranges = this.serializeAnimationRanges();

        // Layer mask
        serializationObject.layerMask = this.layerMask;

        // Alpha
        serializationObject.alphaIndex = this.alphaIndex;
        serializationObject.hasVertexAlpha = this.hasVertexAlpha;

        // Overlay
        serializationObject.overlayAlpha = this.overlayAlpha;
        serializationObject.overlayColor = this.overlayColor.asArray();
        serializationObject.renderOverlay = this.renderOverlay;

        // Fog
        serializationObject.applyFog = this.applyFog;

        // Action Manager
        if (this.actionManager) {
            serializationObject.actions = this.actionManager.serialize(this.name);
        }
    }

    /** @hidden */
    public _syncGeometryWithMorphTargetManager() {
        if (!this.geometry) {
            return;
        }

        this._markSubMeshesAsAttributesDirty();

        let morphTargetManager = this._internalMeshDataInfo._morphTargetManager;
        if (morphTargetManager && morphTargetManager.vertexCount) {
            if (morphTargetManager.vertexCount !== this.getTotalVertices()) {
                Logger.Error("Mesh is incompatible with morph targets. Targets and mesh must all have the same vertices count.");
                this.morphTargetManager = null;
                return;
            }

            for (var index = 0; index < morphTargetManager.numInfluencers; index++) {
                var morphTarget = morphTargetManager.getActiveTarget(index);

                const positions = morphTarget.getPositions();
                if (!positions) {
                    Logger.Error("Invalid morph target. Target must have positions.");
                    return;
                }

                this.geometry.setVerticesData(VertexBuffer.PositionKind + index, positions, false, 3);

                const normals = morphTarget.getNormals();
                if (normals) {
                    this.geometry.setVerticesData(VertexBuffer.NormalKind + index, normals, false, 3);
                }

                const tangents = morphTarget.getTangents();
                if (tangents) {
                    this.geometry.setVerticesData(VertexBuffer.TangentKind + index, tangents, false, 3);
                }

                const uvs = morphTarget.getUVs();
                if (uvs) {
                    this.geometry.setVerticesData(VertexBuffer.UVKind + "_" + index, uvs, false, 2);
                }
            }
        } else {
            var index = 0;

            // Positions
            while (this.geometry.isVerticesDataPresent(VertexBuffer.PositionKind + index)) {
                this.geometry.removeVerticesData(VertexBuffer.PositionKind + index);

                if (this.geometry.isVerticesDataPresent(VertexBuffer.NormalKind + index)) {
                    this.geometry.removeVerticesData(VertexBuffer.NormalKind + index);
                }
                if (this.geometry.isVerticesDataPresent(VertexBuffer.TangentKind + index)) {
                    this.geometry.removeVerticesData(VertexBuffer.TangentKind + index);
                }
                if (this.geometry.isVerticesDataPresent(VertexBuffer.UVKind + index)) {
                    this.geometry.removeVerticesData(VertexBuffer.UVKind + "_" + index);
                }
                index++;
            }
        }
    }

    // Statics
    /** @hidden */
    public static _GroundMeshParser = (parsedMesh: any, scene: Scene): Mesh => {
        throw _DevTools.WarnImport("GroundMesh");
    }

    /**
     * Returns a new Mesh object parsed from the source provided.
     * @param parsedMesh is the source
     * @param scene defines the hosting scene
     * @param rootUrl is the root URL to prefix the `delayLoadingFile` property with
     * @returns a new Mesh
     */
    public static Parse(parsedMesh: any, scene: Scene, rootUrl: string): Mesh {
        var mesh: Mesh;

        if (parsedMesh.type && parsedMesh.type === "GroundMesh") {
            mesh = Mesh._GroundMeshParser(parsedMesh, scene);
        } else {
            mesh = new Mesh(parsedMesh.name, scene);
        }
        mesh.id = parsedMesh.id;

        if (Tags) {
            Tags.AddTagsTo(mesh, parsedMesh.tags);
        }

        mesh.position = Vector3.FromArray(parsedMesh.position);

        if (parsedMesh.metadata !== undefined) {
            mesh.metadata = parsedMesh.metadata;
        }

        if (parsedMesh.rotationQuaternion) {
            mesh.rotationQuaternion = Quaternion.FromArray(parsedMesh.rotationQuaternion);
        } else if (parsedMesh.rotation) {
            mesh.rotation = Vector3.FromArray(parsedMesh.rotation);
        }

        mesh.scaling = Vector3.FromArray(parsedMesh.scaling);

        if (parsedMesh.localMatrix) {
            mesh.setPreTransformMatrix(Matrix.FromArray(parsedMesh.localMatrix));
        } else if (parsedMesh.pivotMatrix) {
            mesh.setPivotMatrix(Matrix.FromArray(parsedMesh.pivotMatrix));
        }

        mesh.setEnabled(parsedMesh.isEnabled);
        mesh.isVisible = parsedMesh.isVisible;
        mesh.infiniteDistance = parsedMesh.infiniteDistance;

        mesh.showBoundingBox = parsedMesh.showBoundingBox;
        mesh.showSubMeshesBoundingBox = parsedMesh.showSubMeshesBoundingBox;

        if (parsedMesh.applyFog !== undefined) {
            mesh.applyFog = parsedMesh.applyFog;
        }

        if (parsedMesh.pickable !== undefined) {
            mesh.isPickable = parsedMesh.pickable;
        }

        if (parsedMesh.alphaIndex !== undefined) {
            mesh.alphaIndex = parsedMesh.alphaIndex;
        }

        mesh.receiveShadows = parsedMesh.receiveShadows;

        mesh.billboardMode = parsedMesh.billboardMode;

        if (parsedMesh.visibility !== undefined) {
            mesh.visibility = parsedMesh.visibility;
        }

        mesh.checkCollisions = parsedMesh.checkCollisions;
        mesh.overrideMaterialSideOrientation = parsedMesh.overrideMaterialSideOrientation;

        if (parsedMesh.isBlocker !== undefined) {
            mesh.isBlocker = parsedMesh.isBlocker;
        }

        mesh._shouldGenerateFlatShading = parsedMesh.useFlatShading;

        // freezeWorldMatrix
        if (parsedMesh.freezeWorldMatrix) {
            mesh._waitingData.freezeWorldMatrix = parsedMesh.freezeWorldMatrix;
        }

        // Parent
        if (parsedMesh.parentId) {
            mesh._waitingParentId = parsedMesh.parentId;
        }

        // Actions
        if (parsedMesh.actions !== undefined) {
            mesh._waitingData.actions = parsedMesh.actions;
        }

        // Overlay
        if (parsedMesh.overlayAlpha !== undefined) {
            mesh.overlayAlpha = parsedMesh.overlayAlpha;
        }

        if (parsedMesh.overlayColor !== undefined) {
            mesh.overlayColor = Color3.FromArray(parsedMesh.overlayColor);
        }

        if (parsedMesh.renderOverlay !== undefined) {
            mesh.renderOverlay = parsedMesh.renderOverlay;
        }

        // Geometry
        mesh.isUnIndexed = !!parsedMesh.isUnIndexed;
        mesh.hasVertexAlpha = parsedMesh.hasVertexAlpha;

        if (parsedMesh.delayLoadingFile) {
            mesh.delayLoadState = Constants.DELAYLOADSTATE_NOTLOADED;
            mesh.delayLoadingFile = rootUrl + parsedMesh.delayLoadingFile;
            mesh._boundingInfo = new BoundingInfo(Vector3.FromArray(parsedMesh.boundingBoxMinimum), Vector3.FromArray(parsedMesh.boundingBoxMaximum));

            if (parsedMesh._binaryInfo) {
                mesh._binaryInfo = parsedMesh._binaryInfo;
            }

            mesh._delayInfo = [];
            if (parsedMesh.hasUVs) {
                mesh._delayInfo.push(VertexBuffer.UVKind);
            }

            if (parsedMesh.hasUVs2) {
                mesh._delayInfo.push(VertexBuffer.UV2Kind);
            }

            if (parsedMesh.hasUVs3) {
                mesh._delayInfo.push(VertexBuffer.UV3Kind);
            }

            if (parsedMesh.hasUVs4) {
                mesh._delayInfo.push(VertexBuffer.UV4Kind);
            }

            if (parsedMesh.hasUVs5) {
                mesh._delayInfo.push(VertexBuffer.UV5Kind);
            }

            if (parsedMesh.hasUVs6) {
                mesh._delayInfo.push(VertexBuffer.UV6Kind);
            }

            if (parsedMesh.hasColors) {
                mesh._delayInfo.push(VertexBuffer.ColorKind);
            }

            if (parsedMesh.hasMatricesIndices) {
                mesh._delayInfo.push(VertexBuffer.MatricesIndicesKind);
            }

            if (parsedMesh.hasMatricesWeights) {
                mesh._delayInfo.push(VertexBuffer.MatricesWeightsKind);
            }

            mesh._delayLoadingFunction = Geometry._ImportGeometry;

            if (SceneLoaderFlags.ForceFullSceneLoadingForIncremental) {
                mesh._checkDelayState();
            }

        } else {
            Geometry._ImportGeometry(parsedMesh, mesh);
        }

        // Material
        if (parsedMesh.materialId) {
            mesh.setMaterialByID(parsedMesh.materialId);
        } else {
            mesh.material = null;
        }

        // Morph targets
        if (parsedMesh.morphTargetManagerId > -1) {
            mesh.morphTargetManager = scene.getMorphTargetManagerById(parsedMesh.morphTargetManagerId);
        }

        // Skeleton
        if (parsedMesh.skeletonId !== undefined && parsedMesh.skeletonId !== null) {
            mesh.skeleton = scene.getLastSkeletonByID(parsedMesh.skeletonId);
            if (parsedMesh.numBoneInfluencers) {
                mesh.numBoneInfluencers = parsedMesh.numBoneInfluencers;
            }
        }

        // Animations
        if (parsedMesh.animations) {
            for (var animationIndex = 0; animationIndex < parsedMesh.animations.length; animationIndex++) {
                var parsedAnimation = parsedMesh.animations[animationIndex];
                const internalClass = _TypeStore.GetClass("BABYLON.Animation");
                if (internalClass) {
                    mesh.animations.push(internalClass.Parse(parsedAnimation));
                }
            }
            Node.ParseAnimationRanges(mesh, parsedMesh, scene);
        }

        if (parsedMesh.autoAnimate) {
            scene.beginAnimation(mesh, parsedMesh.autoAnimateFrom, parsedMesh.autoAnimateTo, parsedMesh.autoAnimateLoop, parsedMesh.autoAnimateSpeed || 1.0);
        }

        // Layer Mask
        if (parsedMesh.layerMask && (!isNaN(parsedMesh.layerMask))) {
            mesh.layerMask = Math.abs(parseInt(parsedMesh.layerMask));
        } else {
            mesh.layerMask = 0x0FFFFFFF;
        }

        // Physics
        if (parsedMesh.physicsImpostor) {
            Mesh._PhysicsImpostorParser(scene, mesh, parsedMesh);
        }

        // Levels
        if (parsedMesh.lodMeshIds) {
            mesh._waitingData.lods = {
                ids: parsedMesh.lodMeshIds,
                distances: (parsedMesh.lodDistances) ? parsedMesh.lodDistances : null,
                coverages: (parsedMesh.lodCoverages) ? parsedMesh.lodCoverages : null
            };
        }

        // Instances
        if (parsedMesh.instances) {
            for (var index = 0; index < parsedMesh.instances.length; index++) {
                var parsedInstance = parsedMesh.instances[index];
                var instance = mesh.createInstance(parsedInstance.name);

                if (parsedInstance.id) {
                    instance.id = parsedInstance.id;
                }

                if (Tags) {
                    if (parsedInstance.tags) {
                        Tags.AddTagsTo(instance, parsedInstance.tags);
                    } else {
                        Tags.AddTagsTo(instance, parsedMesh.tags);
                    }
                }

                instance.position = Vector3.FromArray(parsedInstance.position);

                if (parsedInstance.metadata !== undefined) {
                    instance.metadata = parsedInstance.metadata;
                }

                if (parsedInstance.parentId) {
                    instance._waitingParentId = parsedInstance.parentId;
                }

                if (parsedInstance.isEnabled !== undefined && parsedInstance.isEnabled !== null) {
                    instance.setEnabled(parsedInstance.isEnabled);
                }

                if (parsedInstance.isVisible !== undefined && parsedInstance.isVisible !== null) {
                    instance.isVisible = parsedInstance.isVisible;
                }

                if (parsedInstance.isPickable !== undefined && parsedInstance.isPickable !== null) {
                    instance.isPickable = parsedInstance.isPickable;
                }

                if (parsedInstance.rotationQuaternion) {
                    instance.rotationQuaternion = Quaternion.FromArray(parsedInstance.rotationQuaternion);
                } else if (parsedInstance.rotation) {
                    instance.rotation = Vector3.FromArray(parsedInstance.rotation);
                }

                instance.scaling = Vector3.FromArray(parsedInstance.scaling);

                if (parsedInstance.checkCollisions != undefined && parsedInstance.checkCollisions != null) {
                    instance.checkCollisions = parsedInstance.checkCollisions;
                }
                if (parsedInstance.pickable != undefined && parsedInstance.pickable != null) {
                    instance.isPickable = parsedInstance.pickable;
                }
                if (parsedInstance.showBoundingBox != undefined && parsedInstance.showBoundingBox != null) {
                    instance.showBoundingBox = parsedInstance.showBoundingBox;
                }
                if (parsedInstance.showSubMeshesBoundingBox != undefined && parsedInstance.showSubMeshesBoundingBox != null) {
                    instance.showSubMeshesBoundingBox = parsedInstance.showSubMeshesBoundingBox;
                }
                if (parsedInstance.alphaIndex != undefined && parsedInstance.showSubMeshesBoundingBox != null) {
                    instance.alphaIndex = parsedInstance.alphaIndex;
                }

                // Physics
                if (parsedInstance.physicsImpostor) {
                    Mesh._PhysicsImpostorParser(scene, instance, parsedInstance);
                }

                // Animation
                if (parsedInstance.animations) {
                    for (animationIndex = 0; animationIndex < parsedInstance.animations.length; animationIndex++) {
                        parsedAnimation = parsedInstance.animations[animationIndex];
                        const internalClass = _TypeStore.GetClass("BABYLON.Animation");
                        if (internalClass) {
                            instance.animations.push(internalClass.Parse(parsedAnimation));
                        }
                    }
                    Node.ParseAnimationRanges(instance, parsedInstance, scene);

                    if (parsedInstance.autoAnimate) {
                        scene.beginAnimation(instance, parsedInstance.autoAnimateFrom, parsedInstance.autoAnimateTo, parsedInstance.autoAnimateLoop, parsedInstance.autoAnimateSpeed || 1.0);
                    }
                }
            }
        }

        // Thin instances
        if (parsedMesh.thinInstances) {
            const thinInstances = parsedMesh.thinInstances;

            if (thinInstances.matrixData) {
                mesh.thinInstanceSetBuffer("matrix", new Float32Array(thinInstances.matrixData), 16, false);

                mesh._thinInstanceDataStorage.matrixBufferSize = thinInstances.matrixBufferSize;
                mesh._thinInstanceDataStorage.instancesCount = thinInstances.instancesCount;
            } else {
                mesh._thinInstanceDataStorage.matrixBufferSize = thinInstances.matrixBufferSize;
            }

            if (parsedMesh.thinInstances.userThinInstance) {
                const userThinInstance = parsedMesh.thinInstances.userThinInstance;

                for (const kind in userThinInstance.data) {
                    mesh.thinInstanceSetBuffer(kind, new Float32Array(userThinInstance.data[kind]), userThinInstance.strides[kind], false);
                    mesh._userThinInstanceBuffersStorage.sizes[kind] = userThinInstance.sizes[kind];
                }
            }
        }

        return mesh;
    }

    /**
     * Creates a ribbon mesh. Please consider using the same method from the MeshBuilder class instead
     * @see https://doc.babylonjs.com/how_to/parametric_shapes
     * @param name defines the name of the mesh to create
     * @param pathArray is a required array of paths, what are each an array of successive Vector3. The pathArray parameter depicts the ribbon geometry.
     * @param closeArray creates a seam between the first and the last paths of the path array (default is false)
     * @param closePath creates a seam between the first and the last points of each path of the path array
     * @param offset is taken in account only if the `pathArray` is containing a single path
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param instance defines an instance of an existing Ribbon object to be updated with the passed `pathArray` parameter (https://doc.babylonjs.com/how_to/How_to_dynamically_morph_a_mesh#ribbon)
     * @returns a new Mesh
     */
    public static CreateRibbon(name: string, pathArray: Vector3[][], closeArray: boolean, closePath: boolean, offset: number, scene?: Scene, updatable?: boolean, sideOrientation?: number, instance?: Mesh): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
      * Creates a plane polygonal mesh.  By default, this is a disc. Please consider using the same method from the MeshBuilder class instead
      * @param name defines the name of the mesh to create
      * @param radius sets the radius size (float) of the polygon (default 0.5)
      * @param tessellation sets the number of polygon sides (positive integer, default 64). So a tessellation valued to 3 will build a triangle, to 4 a square, etc
      * @param scene defines the hosting scene
      * @param updatable defines if the mesh must be flagged as updatable
      * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
      * @returns a new Mesh
      */
    public static CreateDisc(name: string, radius: number, tessellation: number, scene: Nullable<Scene> = null, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a box mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param size sets the size (float) of each box side (default 1)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreateBox(name: string, size: number, scene: Nullable<Scene> = null, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
      * Creates a sphere mesh. Please consider using the same method from the MeshBuilder class instead
      * @param name defines the name of the mesh to create
      * @param segments sets the sphere number of horizontal stripes (positive integer, default 32)
      * @param diameter sets the diameter size (float) of the sphere (default 1)
      * @param scene defines the hosting scene
      * @param updatable defines if the mesh must be flagged as updatable
      * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
      * @returns a new Mesh
      */
    public static CreateSphere(name: string, segments: number, diameter: number, scene?: Scene, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
      * Creates a hemisphere mesh. Please consider using the same method from the MeshBuilder class instead
      * @param name defines the name of the mesh to create
      * @param segments sets the sphere number of horizontal stripes (positive integer, default 32)
      * @param diameter sets the diameter size (float) of the sphere (default 1)
      * @param scene defines the hosting scene
      * @returns a new Mesh
      */
    public static CreateHemisphere(name: string, segments: number, diameter: number, scene?: Scene): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a cylinder or a cone mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param height sets the height size (float) of the cylinder/cone (float, default 2)
     * @param diameterTop set the top cap diameter (floats, default 1)
     * @param diameterBottom set the bottom cap diameter (floats, default 1). This value can't be zero
     * @param tessellation sets the number of cylinder sides (positive integer, default 24). Set it to 3 to get a prism for instance
     * @param subdivisions sets the number of rings along the cylinder height (positive integer, default 1)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreateCylinder(name: string, height: number, diameterTop: number, diameterBottom: number, tessellation: number, subdivisions: any, scene?: Scene, updatable?: any, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    // Torus  (Code from SharpDX.org)
    /**
     * Creates a torus mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param diameter sets the diameter size (float) of the torus (default 1)
     * @param thickness sets the diameter size of the tube of the torus (float, default 0.5)
     * @param tessellation sets the number of torus sides (postive integer, default 16)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreateTorus(name: string, diameter: number, thickness: number, tessellation: number, scene?: Scene, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a torus knot mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param radius sets the global radius size (float) of the torus knot (default 2)
     * @param tube sets the diameter size of the tube of the torus (float, default 0.5)
     * @param radialSegments sets the number of sides on each tube segments (positive integer, default 32)
     * @param tubularSegments sets the number of tubes to decompose the knot into (positive integer, default 32)
     * @param p the number of windings on X axis (positive integers, default 2)
     * @param q the number of windings on Y axis (positive integers, default 3)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreateTorusKnot(name: string, radius: number, tube: number, radialSegments: number, tubularSegments: number, p: number, q: number, scene?: Scene, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a line mesh. Please consider using the same method from the MeshBuilder class instead.
     * @param name defines the name of the mesh to create
     * @param points is an array successive Vector3
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param instance is an instance of an existing LineMesh object to be updated with the passed `points` parameter (https://doc.babylonjs.com/how_to/How_to_dynamically_morph_a_mesh#lines-and-dashedlines).
     * @returns a new Mesh
     */
    public static CreateLines(name: string, points: Vector3[], scene: Nullable<Scene> = null, updatable: boolean = false, instance: Nullable<LinesMesh> = null): LinesMesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a dashed line mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param points is an array successive Vector3
     * @param dashSize is the size of the dashes relatively the dash number (positive float, default 3)
     * @param gapSize is the size of the gap between two successive dashes relatively the dash number (positive float, default 1)
     * @param dashNb is the intended total number of dashes (positive integer, default 200)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param instance is an instance of an existing LineMesh object to be updated with the passed `points` parameter (https://doc.babylonjs.com/how_to/How_to_dynamically_morph_a_mesh#lines-and-dashedlines)
     * @returns a new Mesh
     */
    public static CreateDashedLines(name: string, points: Vector3[], dashSize: number, gapSize: number, dashNb: number, scene: Nullable<Scene> = null, updatable?: boolean, instance?: LinesMesh): LinesMesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a polygon mesh.Please consider using the same method from the MeshBuilder class instead
     * The polygon's shape will depend on the input parameters and is constructed parallel to a ground mesh.
     * The parameter `shape` is a required array of successive Vector3 representing the corners of the polygon in th XoZ plane, that is y = 0 for all vectors.
     * You can set the mesh side orientation with the values : Mesh.FRONTSIDE (default), Mesh.BACKSIDE or Mesh.DOUBLESIDE
     * The mesh can be set to updatable with the boolean parameter `updatable` (default false) if its internal geometry is supposed to change once created.
     * Remember you can only change the shape positions, not their number when updating a polygon.
     * @see https://doc.babylonjs.com/how_to/parametric_shapes#non-regular-polygon
     * @param name defines the name of the mesh to create
     * @param shape is a required array of successive Vector3 representing the corners of the polygon in th XoZ plane, that is y = 0 for all vectors
     * @param scene defines the hosting scene
     * @param holes is a required array of arrays of successive Vector3 used to defines holes in the polygon
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param earcutInjection can be used to inject your own earcut reference
     * @returns a new Mesh
     */
    public static CreatePolygon(name: string, shape: Vector3[], scene: Scene, holes?: Vector3[][], updatable?: boolean, sideOrientation?: number, earcutInjection = earcut): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates an extruded polygon mesh, with depth in the Y direction. Please consider using the same method from the MeshBuilder class instead.
     * @see https://doc.babylonjs.com/how_to/parametric_shapes#extruded-non-regular-polygon
     * @param name defines the name of the mesh to create
     * @param shape is a required array of successive Vector3 representing the corners of the polygon in th XoZ plane, that is y = 0 for all vectors
     * @param depth defines the height of extrusion
     * @param scene defines the hosting scene
     * @param holes is a required array of arrays of successive Vector3 used to defines holes in the polygon
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param earcutInjection can be used to inject your own earcut reference
     * @returns a new Mesh
     */
    public static ExtrudePolygon(name: string, shape: Vector3[], depth: number, scene: Scene, holes?: Vector3[][], updatable?: boolean, sideOrientation?: number, earcutInjection = earcut): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates an extruded shape mesh.
     * The extrusion is a parametric shape. It has no predefined shape. Its final shape will depend on the input parameters. Please consider using the same method from the MeshBuilder class instead
     * @see https://doc.babylonjs.com/how_to/parametric_shapes
     * @see https://doc.babylonjs.com/how_to/parametric_shapes#extruded-shapes
     * @param name defines the name of the mesh to create
     * @param shape is a required array of successive Vector3. This array depicts the shape to be extruded in its local space : the shape must be designed in the xOy plane and will be extruded along the Z axis
     * @param path is a required array of successive Vector3. This is the axis curve the shape is extruded along
     * @param scale is the value to scale the shape
     * @param rotation is the angle value to rotate the shape each step (each path point), from the former step (so rotation added each step) along the curve
     * @param cap sets the way the extruded shape is capped. Possible values : Mesh.NO_CAP (default), Mesh.CAP_START, Mesh.CAP_END, Mesh.CAP_ALL
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param instance is an instance of an existing ExtrudedShape object to be updated with the passed `shape`, `path`, `scale` or `rotation` parameters (https://doc.babylonjs.com/how_to/How_to_dynamically_morph_a_mesh#extruded-shape)
     * @returns a new Mesh
     */
    public static ExtrudeShape(name: string, shape: Vector3[], path: Vector3[], scale: number, rotation: number, cap: number, scene: Nullable<Scene> = null, updatable?: boolean, sideOrientation?: number, instance?: Mesh): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates an custom extruded shape mesh.
     * The custom extrusion is a parametric shape.
     * It has no predefined shape. Its final shape will depend on the input parameters.
     * Please consider using the same method from the MeshBuilder class instead
     * @see https://doc.babylonjs.com/how_to/parametric_shapes#extruded-shapes
     * @param name defines the name of the mesh to create
     * @param shape is a required array of successive Vector3. This array depicts the shape to be extruded in its local space : the shape must be designed in the xOy plane and will be extruded along the Z axis
     * @param path is a required array of successive Vector3. This is the axis curve the shape is extruded along
     * @param scaleFunction is a custom Javascript function called on each path point
     * @param rotationFunction is a custom Javascript function called on each path point
     * @param ribbonCloseArray forces the extrusion underlying ribbon to close all the paths in its `pathArray`
     * @param ribbonClosePath forces the extrusion underlying ribbon to close its `pathArray`
     * @param cap sets the way the extruded shape is capped. Possible values : Mesh.NO_CAP (default), Mesh.CAP_START, Mesh.CAP_END, Mesh.CAP_ALL
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param instance is an instance of an existing ExtrudedShape object to be updated with the passed `shape`, `path`, `scale` or `rotation` parameters (https://doc.babylonjs.com/how_to/how_to_dynamically_morph_a_mesh#extruded-shape)
     * @returns a new Mesh
     */
    public static ExtrudeShapeCustom(name: string, shape: Vector3[], path: Vector3[], scaleFunction: Function, rotationFunction: Function, ribbonCloseArray: boolean, ribbonClosePath: boolean, cap: number, scene: Scene, updatable?: boolean, sideOrientation?: number, instance?: Mesh): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates lathe mesh.
     * The lathe is a shape with a symetry axis : a 2D model shape is rotated around this axis to design the lathe.
     * Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param shape is a required array of successive Vector3. This array depicts the shape to be rotated in its local space : the shape must be designed in the xOy plane and will be rotated around the Y axis. It's usually a 2D shape, so the Vector3 z coordinates are often set to zero
     * @param radius is the radius value of the lathe
     * @param tessellation is the side number of the lathe.
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreateLathe(name: string, shape: Vector3[], radius: number, tessellation: number, scene: Scene, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a plane mesh. Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param size sets the size (float) of both sides of the plane at once (default 1)
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @returns a new Mesh
     */
    public static CreatePlane(name: string, size: number, scene: Scene, updatable?: boolean, sideOrientation?: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a ground mesh.
     * Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param width set the width of the ground
     * @param height set the height of the ground
     * @param subdivisions sets the number of subdivisions per side
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @returns a new Mesh
     */
    public static CreateGround(name: string, width: number, height: number, subdivisions: number, scene?: Scene, updatable?: boolean): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a tiled ground mesh.
     * Please consider using the same method from the MeshBuilder class instead
     * @param name defines the name of the mesh to create
     * @param xmin set the ground minimum X coordinate
     * @param zmin set the ground minimum Y coordinate
     * @param xmax set the ground maximum X coordinate
     * @param zmax set the ground maximum Z coordinate
     * @param subdivisions is an object `{w: positive integer, h: positive integer}` (default `{w: 6, h: 6}`). `w` and `h` are the numbers of subdivisions on the ground width and height. Each subdivision is called a tile
     * @param precision is an object `{w: positive integer, h: positive integer}` (default `{w: 2, h: 2}`). `w` and `h` are the numbers of subdivisions on the ground width and height of each tile
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @returns a new Mesh
     */
    public static CreateTiledGround(name: string, xmin: number, zmin: number, xmax: number, zmax: number, subdivisions: { w: number; h: number; }, precision: { w: number; h: number; }, scene: Scene, updatable?: boolean): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a ground mesh from a height map.
     * Please consider using the same method from the MeshBuilder class instead
     * @see https://doc.babylonjs.com/babylon101/height_map
     * @param name defines the name of the mesh to create
     * @param url sets the URL of the height map image resource
     * @param width set the ground width size
     * @param height set the ground height size
     * @param subdivisions sets the number of subdivision per side
     * @param minHeight is the minimum altitude on the ground
     * @param maxHeight is the maximum altitude on the ground
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param onReady  is a callback function that will be called  once the mesh is built (the height map download can last some time)
     * @param alphaFilter will filter any data where the alpha channel is below this value, defaults 0 (all data visible)
     * @returns a new Mesh
     */
    public static CreateGroundFromHeightMap(name: string, url: string, width: number, height: number, subdivisions: number, minHeight: number, maxHeight: number, scene: Scene, updatable?: boolean, onReady?: (mesh: GroundMesh) => void, alphaFilter?: number): GroundMesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a tube mesh.
     * The tube is a parametric shape.
     * It has no predefined shape. Its final shape will depend on the input parameters.
     * Please consider using the same method from the MeshBuilder class instead
     * @see https://doc.babylonjs.com/how_to/parametric_shapes
     * @param name defines the name of the mesh to create
     * @param path is a required array of successive Vector3. It is the curve used as the axis of the tube
     * @param radius sets the tube radius size
     * @param tessellation is the number of sides on the tubular surface
     * @param radiusFunction is a custom function. If it is not null, it overwrittes the parameter `radius`. This function is called on each point of the tube path and is passed the index `i` of the i-th point and the distance of this point from the first point of the path
     * @param cap sets the way the extruded shape is capped. Possible values : Mesh.NO_CAP (default), Mesh.CAP_START, Mesh.CAP_END, Mesh.CAP_ALL
     * @param scene defines the hosting scene
     * @param updatable defines if the mesh must be flagged as updatable
     * @param sideOrientation defines the mesh side orientation (https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation)
     * @param instance is an instance of an existing Tube object to be updated with the passed `pathArray` parameter (https://doc.babylonjs.com/how_to/How_to_dynamically_morph_a_mesh#tube)
     * @returns a new Mesh
     */
    public static CreateTube(name: string, path: Vector3[], radius: number, tessellation: number, radiusFunction: { (i: number, distance: number): number; }, cap: number, scene: Scene, updatable?: boolean, sideOrientation?: number, instance?: Mesh): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
      * Creates a polyhedron mesh.
      * Please consider using the same method from the MeshBuilder class instead.
      * * The parameter `type` (positive integer, max 14, default 0) sets the polyhedron type to build among the 15 embbeded types. Please refer to the type sheet in the tutorial to choose the wanted type
      * * The parameter `size` (positive float, default 1) sets the polygon size
      * * You can overwrite the `size` on each dimension bu using the parameters `sizeX`, `sizeY` or `sizeZ` (positive floats, default to `size` value)
      * * You can build other polyhedron types than the 15 embbeded ones by setting the parameter `custom` (`polyhedronObject`, default null). If you set the parameter `custom`, this overwrittes the parameter `type`
      * * A `polyhedronObject` is a formatted javascript object. You'll find a full file with pre-set polyhedra here : https://github.com/BabylonJS/Extensions/tree/master/Polyhedron
      * * You can set the color and the UV of each side of the polyhedron with the parameters `faceColors` (Color4, default `(1, 1, 1, 1)`) and faceUV (Vector4, default `(0, 0, 1, 1)`)
      * * To understand how to set `faceUV` or `faceColors`, please read this by considering the right number of faces of your polyhedron, instead of only 6 for the box : https://doc.babylonjs.com/how_to/createbox_per_face_textures_and_colors
      * * The parameter `flat` (boolean, default true). If set to false, it gives the polyhedron a single global face, so less vertices and shared normals. In this case, `faceColors` and `faceUV` are ignored
      * * You can also set the mesh side orientation with the values : Mesh.FRONTSIDE (default), Mesh.BACKSIDE or Mesh.DOUBLESIDE
      * * If you create a double-sided mesh, you can choose what parts of the texture image to crop and stick respectively on the front and the back sides with the parameters `frontUVs` and `backUVs` (Vector4). Detail here : https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation
      * * The mesh can be set to updatable with the boolean parameter `updatable` (default false) if its internal geometry is supposed to change once created
      * @param name defines the name of the mesh to create
      * @param options defines the options used to create the mesh
      * @param scene defines the hosting scene
      * @returns a new Mesh
      */
    public static CreatePolyhedron(name: string, options: { type?: number, size?: number, sizeX?: number, sizeY?: number, sizeZ?: number, custom?: any, faceUV?: Vector4[], faceColors?: Color4[], updatable?: boolean, sideOrientation?: number }, scene: Scene): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a sphere based upon an icosahedron with 20 triangular faces which can be subdivided
     * * The parameter `radius` sets the radius size (float) of the icosphere (default 1)
     * * You can set some different icosphere dimensions, for instance to build an ellipsoid, by using the parameters `radiusX`, `radiusY` and `radiusZ` (all by default have the same value than `radius`)
     * * The parameter `subdivisions` sets the number of subdivisions (postive integer, default 4). The more subdivisions, the more faces on the icosphere whatever its size
     * * The parameter `flat` (boolean, default true) gives each side its own normals. Set it to false to get a smooth continuous light reflection on the surface
     * * You can also set the mesh side orientation with the values : Mesh.FRONTSIDE (default), Mesh.BACKSIDE or Mesh.DOUBLESIDE
     * * If you create a double-sided mesh, you can choose what parts of the texture image to crop and stick respectively on the front and the back sides with the parameters `frontUVs` and `backUVs` (Vector4). Detail here : https://doc.babylonjs.com/babylon101/discover_basic_elements#side-orientation
     * * The mesh can be set to updatable with the boolean parameter `updatable` (default false) if its internal geometry is supposed to change once created
     * @param name defines the name of the mesh
     * @param options defines the options used to create the mesh
     * @param scene defines the hosting scene
     * @returns a new Mesh
     * @see https://doc.babylonjs.com/how_to/polyhedra_shapes#icosphere
     */
    public static CreateIcoSphere(name: string, options: { radius?: number, flat?: boolean, subdivisions?: number, sideOrientation?: number, updatable?: boolean }, scene: Scene): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /**
     * Creates a decal mesh.
     * Please consider using the same method from the MeshBuilder class instead.
     * A decal is a mesh usually applied as a model onto the surface of another mesh
     * @param name  defines the name of the mesh
     * @param sourceMesh defines the mesh receiving the decal
     * @param position sets the position of the decal in world coordinates
     * @param normal sets the normal of the mesh where the decal is applied onto in world coordinates
     * @param size sets the decal scaling
     * @param angle sets the angle to rotate the decal
     * @returns a new Mesh
     */
    public static CreateDecal(name: string, sourceMesh: AbstractMesh, position: Vector3, normal: Vector3, size: Vector3, angle: number): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }

    /** Creates a Capsule Mesh
     * @param name defines the name of the mesh.
     * @param options the constructors options used to shape the mesh.
     * @param scene defines the scene the mesh is scoped to.
     * @returns the capsule mesh
     * @see https://doc.babylonjs.com/how_to/capsule_shape
     */
    public static CreateCapsule(name: string, options: ICreateCapsuleOptions, scene: Scene): Mesh {
        throw _DevTools.WarnImport("MeshBuilder");
    }
    // Skeletons

    /**
     * Prepare internal position array for software CPU skinning
     * @returns original positions used for CPU skinning. Useful for integrating Morphing with skeletons in same mesh
     */
    public setPositionsForCPUSkinning(): Float32Array {
        let internalDataInfo = this._internalMeshDataInfo;
        if (!internalDataInfo._sourcePositions) {
            let source = this.getVerticesData(VertexBuffer.PositionKind);
            if (!source) {
                return internalDataInfo._sourcePositions;
            }

            internalDataInfo._sourcePositions = new Float32Array(<any>source);

            if (!this.isVertexBufferUpdatable(VertexBuffer.PositionKind)) {
                this.setVerticesData(VertexBuffer.PositionKind, source, true);
            }
        }
        return internalDataInfo._sourcePositions;
    }

    /**
     * Prepare internal normal array for software CPU skinning
     * @returns original normals used for CPU skinning. Useful for integrating Morphing with skeletons in same mesh.
     */
    public setNormalsForCPUSkinning(): Float32Array {
        let internalDataInfo = this._internalMeshDataInfo;

        if (!internalDataInfo._sourceNormals) {
            let source = this.getVerticesData(VertexBuffer.NormalKind);

            if (!source) {
                return internalDataInfo._sourceNormals;
            }

            internalDataInfo._sourceNormals = new Float32Array(<any>source);

            if (!this.isVertexBufferUpdatable(VertexBuffer.NormalKind)) {
                this.setVerticesData(VertexBuffer.NormalKind, source, true);
            }
        }
        return internalDataInfo._sourceNormals;
    }

    /**
     * Updates the vertex buffer by applying transformation from the bones
     * @param skeleton defines the skeleton to apply to current mesh
     * @returns the current mesh
     */
    public applySkeleton(skeleton: Skeleton): Mesh {
        if (!this.geometry) {
            return this;
        }

        if (this.geometry._softwareSkinningFrameId == this.getScene().getFrameId()) {
            return this;
        }

        this.geometry._softwareSkinningFrameId = this.getScene().getFrameId();

        if (!this.isVerticesDataPresent(VertexBuffer.PositionKind)) {
            return this;
        }
        if (!this.isVerticesDataPresent(VertexBuffer.MatricesIndicesKind)) {
            return this;
        }
        if (!this.isVerticesDataPresent(VertexBuffer.MatricesWeightsKind)) {
            return this;
        }

        const hasNormals = this.isVerticesDataPresent(VertexBuffer.NormalKind);

        let internalDataInfo = this._internalMeshDataInfo;

        if (!internalDataInfo._sourcePositions) {
            var submeshes = this.subMeshes.slice();
            this.setPositionsForCPUSkinning();
            this.subMeshes = submeshes;
        }

        if (hasNormals && !internalDataInfo._sourceNormals) {
            this.setNormalsForCPUSkinning();
        }

        // positionsData checks for not being Float32Array will only pass at most once
        var positionsData = this.getVerticesData(VertexBuffer.PositionKind);

        if (!positionsData) {
            return this;
        }

        if (!(positionsData instanceof Float32Array)) {
            positionsData = new Float32Array(positionsData);
        }

        // normalsData checks for not being Float32Array will only pass at most once
        var normalsData = this.getVerticesData(VertexBuffer.NormalKind);

        if (hasNormals) {
            if (!normalsData) {
                return this;
            }

            if (!(normalsData instanceof Float32Array)) {
                normalsData = new Float32Array(normalsData);
            }
        }

        var matricesIndicesData = this.getVerticesData(VertexBuffer.MatricesIndicesKind);
        var matricesWeightsData = this.getVerticesData(VertexBuffer.MatricesWeightsKind);

        if (!matricesWeightsData || !matricesIndicesData) {
            return this;
        }

        var needExtras = this.numBoneInfluencers > 4;
        var matricesIndicesExtraData = needExtras ? this.getVerticesData(VertexBuffer.MatricesIndicesExtraKind) : null;
        var matricesWeightsExtraData = needExtras ? this.getVerticesData(VertexBuffer.MatricesWeightsExtraKind) : null;

        var skeletonMatrices = skeleton.getTransformMatrices(this);

        var tempVector3 = Vector3.Zero();
        var finalMatrix = new Matrix();
        var tempMatrix = new Matrix();

        var matWeightIdx = 0;
        var inf: number;
        for (var index = 0; index < positionsData.length; index += 3, matWeightIdx += 4) {
            var weight: number;
            for (inf = 0; inf < 4; inf++) {
                weight = matricesWeightsData[matWeightIdx + inf];
                if (weight > 0) {
                    Matrix.FromFloat32ArrayToRefScaled(skeletonMatrices, Math.floor(matricesIndicesData[matWeightIdx + inf] * 16), weight, tempMatrix);
                    finalMatrix.addToSelf(tempMatrix);
                }
            }
            if (needExtras) {
                for (inf = 0; inf < 4; inf++) {
                    weight = matricesWeightsExtraData![matWeightIdx + inf];
                    if (weight > 0) {
                        Matrix.FromFloat32ArrayToRefScaled(skeletonMatrices, Math.floor(matricesIndicesExtraData![matWeightIdx + inf] * 16), weight, tempMatrix);
                        finalMatrix.addToSelf(tempMatrix);
                    }
                }
            }

            Vector3.TransformCoordinatesFromFloatsToRef(internalDataInfo._sourcePositions[index], internalDataInfo._sourcePositions[index + 1], internalDataInfo._sourcePositions[index + 2], finalMatrix, tempVector3);
            tempVector3.toArray(positionsData, index);

            if (hasNormals) {
                Vector3.TransformNormalFromFloatsToRef(internalDataInfo._sourceNormals[index], internalDataInfo._sourceNormals[index + 1], internalDataInfo._sourceNormals[index + 2], finalMatrix, tempVector3);
                tempVector3.toArray(normalsData!, index);
            }

            finalMatrix.reset();
        }

        this.updateVerticesData(VertexBuffer.PositionKind, positionsData);
        if (hasNormals) {
            this.updateVerticesData(VertexBuffer.NormalKind, normalsData!);
        }

        return this;
    }

    // Tools

    /**
     * Returns an object containing a min and max Vector3 which are the minimum and maximum vectors of each mesh bounding box from the passed array, in the world coordinates
     * @param meshes defines the list of meshes to scan
     * @returns an object `{min:` Vector3`, max:` Vector3`}`
     */
    public static MinMax(meshes: AbstractMesh[]): { min: Vector3; max: Vector3 } {
        var minVector: Nullable<Vector3> = null;
        var maxVector: Nullable<Vector3> = null;

        meshes.forEach(function(mesh) {
            let boundingInfo = mesh.getBoundingInfo();

            let boundingBox = boundingInfo.boundingBox;
            if (!minVector || !maxVector) {
                minVector = boundingBox.minimumWorld;
                maxVector = boundingBox.maximumWorld;
            } else {
                minVector.minimizeInPlace(boundingBox.minimumWorld);
                maxVector.maximizeInPlace(boundingBox.maximumWorld);
            }
        });

        if (!minVector || !maxVector) {
            return {
                min: Vector3.Zero(),
                max: Vector3.Zero()
            };
        }

        return {
            min: minVector,
            max: maxVector
        };
    }

    /**
     * Returns the center of the `{min:` Vector3`, max:` Vector3`}` or the center of MinMax vector3 computed from a mesh array
     * @param meshesOrMinMaxVector could be an array of meshes or a `{min:` Vector3`, max:` Vector3`}` object
     * @returns a vector3
     */
    public static Center(meshesOrMinMaxVector: { min: Vector3; max: Vector3 } | AbstractMesh[]): Vector3 {
        var minMaxVector = (meshesOrMinMaxVector instanceof Array) ? Mesh.MinMax(meshesOrMinMaxVector) : meshesOrMinMaxVector;
        return Vector3.Center(minMaxVector.min, minMaxVector.max);
    }

    /**
     * Merge the array of meshes into a single mesh for performance reasons.
     * @param meshes defines he vertices source.  They should all be of the same material.  Entries can empty
     * @param disposeSource when true (default), dispose of the vertices from the source meshes
     * @param allow32BitsIndices when the sum of the vertices > 64k, this must be set to true
     * @param meshSubclass when set, vertices inserted into this Mesh.  Meshes can then be merged into a Mesh sub-class.
     * @param subdivideWithSubMeshes when true (false default), subdivide mesh to his subMesh array with meshes source.
     * @param multiMultiMaterials when true (false default), subdivide mesh and accept multiple multi materials, ignores subdivideWithSubMeshes.
     * @returns a new mesh
     */
    public static MergeMeshes(meshes: Array<Mesh>, disposeSource = true, allow32BitsIndices?: boolean, meshSubclass?: Mesh, subdivideWithSubMeshes?: boolean, multiMultiMaterials?: boolean): Nullable<Mesh> {
        var index: number;
        if (!allow32BitsIndices) {
            var totalVertices = 0;

            // Counting vertices
            for (index = 0; index < meshes.length; index++) {
                if (meshes[index]) {
                    totalVertices += meshes[index].getTotalVertices();

                    if (totalVertices >= 65536) {
                        Logger.Warn("Cannot merge meshes because resulting mesh will have more than 65536 vertices. Please use allow32BitsIndices = true to use 32 bits indices");
                        return null;
                    }
                }
            }
        }
        if (multiMultiMaterials) {
            var newMultiMaterial: Nullable<MultiMaterial> = null;
            var subIndex: number;
            var matIndex: number;
            subdivideWithSubMeshes = false;
        }
        var materialArray: Array<Material> = new Array<Material>();
        var materialIndexArray: Array<number> = new Array<number>();
        // Merge
        var vertexData: Nullable<VertexData> = null;
        var otherVertexData: VertexData;
        var indiceArray: Array<number> = new Array<number>();
        var source: Nullable<Mesh> = null;
        for (index = 0; index < meshes.length; index++) {
            if (meshes[index]) {
                var mesh = meshes[index];
                if (mesh.isAnInstance) {
                    Logger.Warn("Cannot merge instance meshes.");
                    return null;
                }

                const wm = mesh.computeWorldMatrix(true);
                otherVertexData = VertexData.ExtractFromMesh(mesh, true, true);
                otherVertexData.transform(wm);

                if (vertexData) {
                    vertexData.merge(otherVertexData, allow32BitsIndices);
                } else {
                    vertexData = otherVertexData;
                    source = mesh;
                }
                if (subdivideWithSubMeshes) {
                    indiceArray.push(mesh.getTotalIndices());
                }
                if (multiMultiMaterials) {
                    if (mesh.material) {
                        var material = mesh.material;
                        if (material instanceof MultiMaterial) {
                            for (matIndex = 0; matIndex < material.subMaterials.length; matIndex++) {
                                if (materialArray.indexOf(<Material>material.subMaterials[matIndex]) < 0) {
                                    materialArray.push(<Material>material.subMaterials[matIndex]);
                                }
                            }
                            for (subIndex = 0; subIndex < mesh.subMeshes.length; subIndex++) {
                                materialIndexArray.push(materialArray.indexOf(<Material>material.subMaterials[mesh.subMeshes[subIndex].materialIndex]));
                                indiceArray.push(mesh.subMeshes[subIndex].indexCount);
                            }
                        } else {
                            if (materialArray.indexOf(<Material>material) < 0) {
                                materialArray.push(<Material>material);
                            }
                            for (subIndex = 0; subIndex < mesh.subMeshes.length; subIndex++) {
                                materialIndexArray.push(materialArray.indexOf(<Material>material));
                                indiceArray.push(mesh.subMeshes[subIndex].indexCount);
                            }
                        }
                    } else {
                        for (subIndex = 0; subIndex < mesh.subMeshes.length; subIndex++) {
                            materialIndexArray.push(0);
                            indiceArray.push(mesh.subMeshes[subIndex].indexCount);
                        }
                    }
                }
            }
        }

        source = <Mesh>source;

        if (!meshSubclass) {
            meshSubclass = new Mesh(source.name + "_merged", source.getScene());
        }

        (<VertexData>vertexData).applyToMesh(meshSubclass);

        // Setting properties
        meshSubclass.checkCollisions = source.checkCollisions;
        meshSubclass.overrideMaterialSideOrientation = source.overrideMaterialSideOrientation;

        // Cleaning
        if (disposeSource) {
            for (index = 0; index < meshes.length; index++) {
                if (meshes[index]) {
                    meshes[index].dispose();
                }
            }
        }

        // Subdivide
        if (subdivideWithSubMeshes || multiMultiMaterials) {

            //-- removal of global submesh
            meshSubclass.releaseSubMeshes();
            index = 0;
            var offset = 0;

            //-- apply subdivision according to index table
            while (index < indiceArray.length) {
                SubMesh.CreateFromIndices(0, offset, indiceArray[index], meshSubclass);
                offset += indiceArray[index];
                index++;
            }
        }

        if (multiMultiMaterials) {
            newMultiMaterial = new MultiMaterial(source.name + "_merged", source.getScene());
            newMultiMaterial.subMaterials = materialArray;
            for (subIndex = 0; subIndex < meshSubclass.subMeshes.length; subIndex++) {
                meshSubclass.subMeshes[subIndex].materialIndex = materialIndexArray[subIndex];
            }
            meshSubclass.material = newMultiMaterial;
        } else {
            meshSubclass.material = source.material;
        }

        return meshSubclass;
    }

    /** @hidden */
    public addInstance(instance: InstancedMesh) {
        instance._indexInSourceMeshInstanceArray = this.instances.length;
        this.instances.push(instance);
    }

    /** @hidden */
    public removeInstance(instance: InstancedMesh) {
        // Remove from mesh
        const index = instance._indexInSourceMeshInstanceArray;
        if (index != -1) {
            if (index !== this.instances.length - 1) {
                const last = this.instances[this.instances.length - 1];
                this.instances[index] = last;
                last._indexInSourceMeshInstanceArray = index;
            }

            instance._indexInSourceMeshInstanceArray = -1;
            this.instances.pop();
        }
    }
}

_TypeStore.RegisteredTypes["BABYLON.Mesh"] = Mesh;