Add external triangle scene GLTF and update file import handling

fixtures/assets/external-triangle/scene.gltf

@@ -0,0 +1,65 @@
+{
+  "asset": {
+    "version": "2.0",
+    "generator": "webeditor3d fixture"
+  },
+  "scene": 0,
+  "scenes": [
+    {
+      "name": "External Triangle Scene",
+      "nodes": [0]
+    }
+  ],
+  "nodes": [
+    {
+      "mesh": 0,
+      "name": "External Triangle Node"
+    }
+  ],
+  "meshes": [
+    {
+      "name": "External Triangle Mesh",
+      "primitives": [
+        {
+          "attributes": {
+            "POSITION": 0
+          },
+          "material": 0
+        }
+      ]
+    }
+  ],
+  "materials": [
+    {
+      "name": "External Material",
+      "pbrMetallicRoughness": {
+        "baseColorFactor": [0.2, 0.6, 0.85, 1],
+        "metallicFactor": 0,
+        "roughnessFactor": 1
+      }
+    }
+  ],
+  "buffers": [
+    {
+      "byteLength": 36,
+      "uri": "triangle.bin"
+    }
+  ],
+  "bufferViews": [
+    {
+      "buffer": 0,
+      "byteOffset": 0,
+      "byteLength": 36
+    }
+  ],
+  "accessors": [
+    {
+      "bufferView": 0,
+      "componentType": 5126,
+      "count": 3,
+      "type": "VEC3",
+      "min": [0, 0, 0],
+      "max": [1, 1, 0]
+    }
+  ]
+}

src/app/App.tsx

@@ -45,6 +45,7 @@ import {
 } from "../assets/model-instance-labels";
 import {
   importModelAssetFromFile,
+  importModelAssetFromFiles,
   loadModelAssetFromStorage,
   disposeModelTemplate,
   type ImportedModelAssetResult,
@@ -1938,9 +1939,9 @@ export function App({ store, initialStatusMessage }: AppProps) {
 
   const handleImportModelChange = async (event: ChangeEvent<HTMLInputElement>) => {
     const input = event.currentTarget;
-    const file = input.files?.[0];
+    const files = Array.from(input.files ?? []);
 
-    if (file === undefined) {
+    if (files.length === 0) {
       return;
     }
 
@@ -1953,7 +1954,9 @@ export function App({ store, initialStatusMessage }: AppProps) {
     let importedModelForCleanup: ImportedModelAssetResult | null = null;
 
     try {
-      const importedModel = await importModelAssetFromFile(file, projectAssetStorage);
+      const importedModel = files.length === 1
+        ? await importModelAssetFromFile(files[0], projectAssetStorage)
+        : await importModelAssetFromFiles(files, projectAssetStorage);
       importedModelForCleanup = importedModel;
 
       store.executeCommand(
@@ -4014,6 +4017,7 @@ export function App({ store, initialStatusMessage }: AppProps) {
         ref={importModelInputRef}
         className="visually-hidden"
         type="file"
+        multiple
         accept=".glb,.gltf,model/gltf-binary,model/gltf+json,application/octet-stream"
         onChange={handleImportModelChange}
       />

tests/serialization/project-asset-storage.test.ts

@@ -4,21 +4,31 @@ import { createProjectAssetStorageKey } from "../../src/assets/project-assets";
 import { createInMemoryProjectAssetStorage } from "../../src/assets/project-asset-storage";
 
 describe("project asset storage", () => {
-  it("stores, clones, and deletes binary asset payloads", async () => {
+  it("stores, clones, and deletes binary asset file packages", async () => {
     const storage = createInMemoryProjectAssetStorage();
     const storageKey = createProjectAssetStorageKey("asset-model-triangle");
     const bytes = new Uint8Array([0, 1, 2, 3, 4]).buffer;
+    const sidecarBytes = new Uint8Array([9, 8, 7]).buffer;
 
     await storage.putAsset(storageKey, {
-      bytes,
+      files: {
-      mimeType: "model/gltf+json"
+        "tiny-triangle.gltf": {
+          bytes,
+          mimeType: "model/gltf+json"
+        },
+        "triangle.bin": {
+          bytes: sidecarBytes,
+          mimeType: "application/octet-stream"
+        }
+      }
     });
 
     const loadedAsset = await storage.getAsset(storageKey);
 
     expect(loadedAsset).not.toBeNull();
-    expect(loadedAsset?.mimeType).toBe("model/gltf+json");
+    expect(Object.keys(loadedAsset?.files ?? {})).toEqual(["tiny-triangle.gltf", "triangle.bin"]);
-    expect(Array.from(new Uint8Array(loadedAsset?.bytes ?? new ArrayBuffer(0)))).toEqual([0, 1, 2, 3, 4]);
+    expect(Array.from(new Uint8Array(loadedAsset?.files["tiny-triangle.gltf"].bytes ?? new ArrayBuffer(0)))).toEqual([0, 1, 2, 3, 4]);
+    expect(Array.from(new Uint8Array(loadedAsset?.files["triangle.bin"].bytes ?? new ArrayBuffer(0)))).toEqual([9, 8, 7]);
 
     await storage.deleteAsset(storageKey);