AEB-57: fix Babylon loader update

frontend/components/model/ModelViewer.tsx

@@ -11,9 +11,10 @@ import {
   Color4,
   AbstractMesh,
   Nullable,
-  SceneLoader
+  ImportMeshAsync
 } from '@babylonjs/core'
 import '@babylonjs/loaders'
+
 import LoadingSpinner from '../ui/LoadingSpinner'
 
 
@@ -59,6 +60,12 @@ const ModelViewer: React.FC<ModelViewerProps> = ({
     const engine = new Engine(canvas, true)
     engineRef.current = engine
 
+    engine.runRenderLoop(() => {
+      if (!isDisposedRef.current && sceneRef.current) {
+        sceneRef.current.render()
+      }
+    })
+
     const scene = new Scene(engine)
     sceneRef.current = scene
 
@@ -88,12 +95,6 @@ const ModelViewer: React.FC<ModelViewerProps> = ({
     fillLight.intensity = 0.3
     fillLight.diffuse = new Color3(0.8, 0.8, 1)
 
-    engine.runRenderLoop(() => {
-      if (!isDisposedRef.current) {
-        scene.render()
-      }
-    })
-
     const handleResize = () => {
       if (!isDisposedRef.current) {
         engine.resize()
@@ -124,6 +125,9 @@ const ModelViewer: React.FC<ModelViewerProps> = ({
       if (!sceneRef.current || isDisposedRef.current) {
         return
       }
+ 
+      const oldMeshes = sceneRef.current.meshes.slice();
+      oldMeshes.forEach(m => m.dispose());
 
       setIsLoading(true)
       setLoadingProgress(0)
@@ -142,12 +146,7 @@ const ModelViewer: React.FC<ModelViewerProps> = ({
       }, 100)
       
       try {
-        const result = await SceneLoader.ImportMeshAsync(
-          '',
-          modelPath,
-          '',
-          sceneRef.current
-        )
+        const result = await ImportMeshAsync(modelPath, sceneRef.current)
 
         clearInterval(progressInterval)
         setLoadingProgress(100)
@@ -196,7 +195,8 @@ const ModelViewer: React.FC<ModelViewerProps> = ({
       }
     }
 
-    loadModel()
+    // Загрузка модлеи начинается после появления спиннера
+    requestIdleCallback(() => loadModel(), { timeout: 50 })
   }, [modelPath, onError, onModelLoaded])
 
   return (