glTF Loader: Allow to async return after all resources are loaded (#1029

)

modules/addons/src/gltf/gltf-scenegraph-loader.js

@@ -1,7 +1,14 @@
+/* global window */
 import {GLTFParser} from '@loaders.gl/gltf';
 import {DracoDecoder} from '@loaders.gl/draco';
 import createGLTFObjects from './create-gltf-objects';
 
+async function waitWhileCondition(condition) {
+  while (condition()) {
+    await new Promise(resolve => window.requestAnimationFrame(resolve));
+  }
+}
+
 async function parse(data, options, uri, loader) {
   const gltfParser = new GLTFParser();
   const gltf = await gltfParser.parse(data, {
@@ -10,7 +17,25 @@ async function parse(data, options, uri, loader) {
     DracoDecoder
   });
 
-  return Object.assign({gltfParser, gltf}, createGLTFObjects(options.gl, gltf, options));
+  const gltfObjects = createGLTFObjects(options.gl, gltf, options);
+
+  if (options.waitForFullLoad) {
+    const remaining = [];
+
+    gltfObjects.scenes.forEach(scene => {
+      scene.traverse(model => {
+        Object.values(model.model.program.uniforms).forEach(uniform => {
+          if (uniform.loaded === false) {
+            remaining.push(uniform);
+          }
+        });
+      });
+    });
+
+    await waitWhileCondition(() => remaining.some(uniform => !uniform.loaded));
+  }
+
+  return Object.assign({gltfParser, gltf}, gltfObjects);
 }
 
 export const GLBScenegraphLoader = {