fix(app): render bounding boxes on media panel without points (#3158)

* WB-16623 coercing empty point to default, targeting camera on bounding box when point cloud empty

* code style cleanup

weave-js/src/common/util/SdkPointCloudToBabylon.test.ts

@@ -4,6 +4,7 @@ import {
   DEFAULT_POINT_COLOR,
   getFilteringOptionsForPointCloud,
   getVertexCompatiblePositionsAndColors,
+  loadPointCloud,
   MAX_BOUNDING_BOX_LABELS_FOR_DISPLAY,
   MaxAlphaValue,
 } from './SdkPointCloudToBabylon';
@@ -174,3 +175,16 @@ describe('getFilteringOptionsForPointCloud', () => {
     expect(newClassIdToLabel.get(49)).toEqual('label49');
   });
 });
+describe('loadPointCloud', () => {
+  it('appropriate defaults set when loading point cloud from file', () => {
+    const fileContents = JSON.stringify({
+      boxes: [],
+      points: [[]],
+      type: 'lidar/beta',
+      vectors: [],
+    });
+    const babylonPointCloud = loadPointCloud(fileContents);
+    expect(babylonPointCloud.points).toHaveLength(1);
+    expect(babylonPointCloud.points[0].position).toEqual([0, 0, 0]);
+  });
+});

weave-js/src/common/util/SdkPointCloudToBabylon.ts

@@ -160,7 +160,7 @@ export const handlePoints = (object3D: Object3DScene): ScenePoint[] => {
   // Draw Points
   return truncatedPoints.map(point => {
     const [x, y, z, r, g, b] = point;
-    const position: Position = [x, y, z];
+    const position: Position = [x ?? 0, y ?? 0, z ?? 0];
     const category = r;
 
     if (r !== undefined && g !== undefined && b !== undefined) {

weave-js/src/common/util/render_babylon.ts

@@ -394,6 +394,15 @@ const pointCloudScene = (
   // Apply vertexData to custom mesh
   vertexData.applyToMesh(pcMesh);
 
+  // A file without any points defined still includes a single, empty "point".
+  // In order to play nice with Babylon, we position this empty point at 0,0,0.
+  // Hence, a pointCloud with a single point at 0,0,0 is likely empty.
+  const isEmpty =
+    pointCloud.points.length === 1 &&
+    pointCloud.points[0].position[0] === 0 &&
+    pointCloud.points[0].position[1] === 0 &&
+    pointCloud.points[0].position[2] === 0;
+
   camera.parent = pcMesh;
 
   const pcMaterial = new Babylon.StandardMaterial('mat', scene);
@@ -472,8 +481,8 @@ const pointCloudScene = (
         new Vector3(edges.length * 2, edges.length * 2, edges.length * 2)
       );
 
-    // If we are iterating over camera, target a box
-    if (index === meta?.cameraIndex) {
+    // If we are iterating over camera or the cloud is empty, target a box
+    if (index === meta?.cameraIndex || (index === 0 && isEmpty)) {
       camera.position = center.add(new Vector3(0, 0, 1000));
       camera.target = center;
       camera.zoomOn([lines]);