iPhone LiDAR
  -> ARKit sceneDepth
  -> depth + confidence + camera intrinsics + device pose
  -> compact u16 millimeter wire frame
  -> WebSocket relay
  -> browser point cloud
  -> future RuView HAL / fusion ingest

The native path is the sensor. The web path is a receiver and visualization surface. Mobile Safari does not expose ARKit scene depth directly to ordinary web pages, so the browser cannot replace the native capture layer on iPhone today.

Native iPhone path

Create an iOS SwiftUI app target in Xcode, deployment target iOS 17 or newer, then add the files under native/RuViewLiDAR/ to the target.

Add this Info.plist value:

<key>NSCameraUsageDescription</key>
<string>RuView uses the camera and LiDAR scanner to capture local depth geometry.</string>

Run on a physical LiDAR capable iPhone or iPad. The simulator does not provide LiDAR scene depth.

The app requests ARWorldTrackingConfiguration with .sceneDepth, checks supportsFrameSemantics, extracts ARDepthData.depthMap and confidenceMap, and never transmits RGB camera frames.

Browser path

cd integrations/iphone-lidar/web
npm install
npm test
npm start

Open http://HOST:8787 in a browser. In the iPhone app set the endpoint to:

ws://HOST:8787/ws/lidar

For production use TLS and wss://.

Wire format

Schema: ruview.lidar.depth.v1

Depth is downsampled by 2 in each dimension by default and streamed at a maximum of 15 FPS. Each depth sample is encoded as little endian UInt16 millimeters plus one UInt8 confidence value. This reduces the depth payload from roughly 196 KB per 256 x 192 Float32 frame to roughly 37 KB per 128 x 96 frame before base64 and JSON overhead.

At 15 FPS that is approximately 0.75 MB/s after base64 overhead, versus roughly 8 MB/s for uncompressed Float32 JSON at full resolution.

Privacy and governance

The initial implementation labels provenance as source=live and privacyClass=geometry-only. It sends depth geometry, confidence, camera intrinsics, pose, sequence, and wall clock timestamp. It does not send RGB imagery.

Production integration should terminate the WebSocket inside RuView, authenticate the device using the existing sensor identity path, convert each frame into ruview-hal::Observation, and attach witness receipts before fusion or persistence.

Acceptance test

Run the relay and browser viewer.
Run the native app on a LiDAR capable iPhone.
Start LiDAR capture and enable streaming.
Move the phone through a room.
Verify the browser shows a changing point cloud, sequence increases monotonically, latency stays below 150 ms on a local WiFi network, and no RGB payload is present in captured WebSocket frames.