Mocopi Integration

Sony mocopi is a mobile motion capture system that can stream skeletal data over a local network. Using the MocopiReceiver package, you can drive AR avatars and interactive characters in Spectacles lenses using real-time full-body motion capture.

Official site: Sony mocopi

Connection Workflow

1. Host Server: Run the mocopi desktop/mobile app and enable "Send" mode (UDP/WebSocket).
2. WebSocket Client: Use MocopiWebSocketClient in Lens Studio to connect to the IP/Port of the host.
3. Skeleton Mapping: Listen for the SkeletonDefinition, which contains the hierarchical bone structure.
4. Frame Processing: Update your 3D avatar bones every time a FrameData packet arrives.

Basic Implementation

The MocopiMainController manages the communication between the network client and the avatar.

import { MocopiWebSocketClient } from "./MocopiWebSocketClient";
import { MocopiAvatarController } from "./MocopiAvatarController";

@component
export class MyMocopiBridge extends BaseScriptComponent {
  @input webSocketClient: MocopiWebSocketClient;
  @input avatarController: MocopiAvatarController;

  onAwake() {
    this.webSocketClient.onSkeletonReceived = (skeleton) => {
      // Initialize the avatar mesh with the correct bone count and hierarchy
      this.avatarController.initializeAvatar(skeleton);
    };

    this.webSocketClient.onFrameReceived = (frame) => {
      // Apply real-time rotations/positions to the avatar bones
      this.avatarController.updateFrame(frame);
    };
  }

  public connect() {
    this.webSocketClient.connect();
  }
}

Avatar Configuration

Your 3D model must be rigged with a hierarchy that matches the mocopi bone structure (hips, spine, neck, head, and limbs).

[!TIP] Use the ResetButton pattern in your lens to allow users to recalibrate the avatar's world position if it drifts from the tracking center.

Reference Example

The logic below is extracted from the official MocopiReceiver.lspkg package, demonstrating the main orchestration logic for real-time motion capture.

See the reference guide for details.