GLTF - Load Skin Async

GLTF2 - Custom Load Skin Async Support

loaders/src/glTF/2.0/glTFLoader.ts

@@ -932,6 +932,11 @@ export class GLTFLoader implements IGLTFLoader {
     }
 
     private _loadSkinAsync(context: string, node: INode, skin: ISkin): Promise<void> {
+        const extensionPromise = this._extensionsLoadSkinAsync(context, node, skin);
+        if (extensionPromise) {
+            return extensionPromise;
+        }
+
         const assignSkeleton = (skeleton: Skeleton) => {
             this._forEachPrimitive(node, (babylonMesh) => {
                 babylonMesh.skeleton = skeleton;
@@ -2159,6 +2164,10 @@ export class GLTFLoader implements IGLTFLoader {
         return this._applyExtensions(animation, "loadAnimation", (extension) => extension.loadAnimationAsync && extension.loadAnimationAsync(context, animation));
     }
 
+    private _extensionsLoadSkinAsync(context: string, node: INode, skin: ISkin): Nullable<Promise<void>> {
+        return this._applyExtensions(skin, "loadSkin", (extension) => extension.loadSkinAsync && extension.loadSkinAsync(context, node, skin));
+    }
+
     private _extensionsLoadUriAsync(context: string, property: IProperty, uri: string): Nullable<Promise<ArrayBufferView>> {
         return this._applyExtensions(property, "loadUri", (extension) => extension._loadUriAsync && extension._loadUriAsync(context, property, uri));
     }

loaders/src/glTF/2.0/glTFLoaderExtension.ts

@@ -8,7 +8,7 @@ import { BaseTexture } from "babylonjs/Materials/Textures/baseTexture";
 import { Mesh } from "babylonjs/Meshes/mesh";
 import { IDisposable } from "babylonjs/scene";
 
-import { IScene, INode, ICamera, IMeshPrimitive, IMaterial, ITextureInfo, IAnimation } from "./glTFLoaderInterfaces";
+import { IScene, INode, ISkin, ICamera, IMeshPrimitive, IMaterial, ITextureInfo, IAnimation } from "./glTFLoaderInterfaces";
 import { IGLTFLoaderExtension as IGLTFBaseLoaderExtension } from "../glTFFileLoader";
 import { IProperty } from 'babylonjs-gltf2interface';
 
@@ -105,6 +105,15 @@ export interface IGLTFLoaderExtension extends IGLTFBaseLoaderExtension, IDisposa
     loadAnimationAsync?(context: string, animation: IAnimation): Nullable<Promise<AnimationGroup>>;
 
     /**
+     * Define this method to modify the default behavior when loading skins.
+     * @param context The context when loading the asset
+     * @param node The glTF node property
+     * @param skin The glTF skin property
+     * @returns A promise that resolves with the loaded Babylon skeleton when the load is complete or null if not handled
+     */
+    loadSkinAsync?(context: string, node: INode, skin: ISkin): Nullable<Promise<void>>;
+    
+    /**
      * Define this method to modify the default behavior when loading uris.
      * @param context The context when loading the asset
      * @param property The glTF property associated with the uri