NaturalPoint MotionBuilder Plugin
User's Guide


Contents

1. Overview
2. OptiTrack Manager
3. OptiTrack Optical
4. Step-By-Step
5. Recording Optical Data


1. Overview

The NaturalPoint OptiTrack MotionBuilder Plugin is a MotionBuilder Device Plugin that allows users to stream live OptiTrack marker data onto a MotionBuilder Actor in real time.

The plugin consists of two devices:

OptiTrack Manager A device that manages communication between the OptiTrack host application and OptiTrack plugin devices
OptiTrack Optical A MotionBuilder Optical Device that maps optical marker data to a MotionBuilder Actor.

There is a one-to-many relationship between the OptiTrack Manager and the OptiTrack Optical devices.

 

2. OptiTrack Manager

The OptiTrack Manager is the connection point between the OptiTrack host application and MotionBuilder. To create this device, simply drag the OptiTrack Manager from the Motion Builder Asset Browser into the Viewer window or Scene browser.

Once you have create an OptiTrack Manager device, you can adjust its settings and connect to OptiTrack.

OptiTrack Manager Settings

1. Device Settings: The standard MotionBuilder Device Settings dialog.

Online

Click this box to connect to OptiTrack.

Red Not connected
Yellow Connected, not streaming
Green Connected and streaming

 
Live Indicates whether data is coming from a live device (checked ) or from a recorded take.
Recording Records data from the device to the curent take

Note : For more information on Device Settings, please refer to the MotionBuilder Help.

2. Server Settings: Specify the network connection to OptiTrack.

Server

Type of server to connect to.

OptiTrack Server Address IP address of the system the OptiTrack host application is running on.
MotionBuilder Address IP address of the system MotionBuilder is running on. Because a system may contain more than one network card, this box allows you to specify the specific IP address directly.

3. Global Settings

Frame Ratio (1:x)

Ratio of OptiTrack frames to MotionBuilder frames.
Frame Offset Number of frames OptiTrack data is offset from MotionBuilder frame data.

 

3. OptiTrack Optical

The OptiTrack Optical device represents a single mapping between an OptiTrack MarkerSet and a MotionBuilder Actor. To create this device, simply drag the OptiTrack Optical from the Motion Builder Asset Browser into the Viewer window or Scene browser.

Once you have created an OptiTrack Optical device, you can adjust its settings and connect it to both an OptiTrack Manager and a Motion Builder Actor.

1. Device Settings: The standard MotionBuilder Device Settings dialog.

Online

Click this box to connect to the specified MarkerSet via the OptiTrack Manager.

Red Not connected
Yellow Connected, not streaming
Green Connected and streaming
Live Indicates whether data is coming from a live device (checked ) or from a recorded take.
Recording Records data from the device to the curent take

Note : For more information on Device Settings, please refer to the MotionBuilder Help.

2. Optical Model: Sets the mapping between mocap marker set and MotionBuilder "opticals"

Optical Model

Specified the MotionBuilder "Opticals" model to map the markers to.

Generate a new Optical model / Update the current optical model

Adds/updates the current MarkerSet from OptiTrack to list of MotionBuilder "Opticals" model.
Damping Time Device damping time .

3. Global Settings

OptiTrack Manager

The OptiTrack manager device for this optical device
OptiTrack MarkerSet

The name of the OptiTrack MarkerSet this optical is binding to.
MarkerSet Scale The global scale factor to be applied to the marker data before mapping to the actor.

Note! The OptiTrack Manager property must be set before you can begin streaming from OptiTrack to MotionBuilder.

 

4. Step-ByStep

The following is a quick, step-by-step process for connecting to Arena

  1. Start Arena

  2. Configure Arena for Streaming Data

  3. Start MotionBuilder

  4. In the MotionBuilder Asset Browser Window -> Devices window. You should see:

    OptiTrack Manager
    OptiTrack Optical


  5. Within MotionBuilder, drag each one into the Navigator (Or Viewer) pane. An instance will be created under the 'Devices' node

  6. Within MotionBuilder, configure the OptiTrack Manager device:
    6.1 In the Navigator window, select OptiTrack Manager from the Devices node.
    6.2 Verify IP address settings
    6.3 Click on the 'Online' checkbox - it should change from red to yellow

  7. Within MotionBuilder, Configure OptiTrack Optical:
    7.1 In the Navigator window, select OptiTrack Optical from the Devices node
    7.2 Click on the 'Online' checkbox - it should change from red to yellow
    7.3 In the 'OptiTrack MarkerSet' Dropdown, select the name of a currently defined MarkerSet in Arena
    7.4 Press the 'Generate new optical model' button
    7.5 In the Navigator window, under the 'Opticals' node, you should see a new the marker list. This indicates the plugin has successfully retrieved the marker list from OptiTrack

  8. Within Arena, Start streaming data

  9. Within MotionBuilder, View data
    9.1 The marker set should be animating in the viewer
    9.2 The 'online' check boxes should be green, indicating streaming mode

 

5. Recording Optical Data

The OptiTrack Optical device can record optical data to the current MotionBuilder take. The following step-by-step procedure can be used to record data:

  1. Arena -> Start
  2. Arena -> Load skl
  3. Arena -> Load pt data
  4. Arena -> Settings -> Other-> IP -> 127.0.0.1
  5. Arena -> Settings -> Other -> Click "Stream Frames"
  6. Arena -> Play
  7. MB -> Start
  8. MB -> Create OptiTrack Manager
  9. MB -> Manager -> Online
  10. MB -> Manager -> Uncheck "Live"
  11. MB -> Create OptiTrack Optical
  12. MB -> Optical -> Online
  13. MB -> Optical -> Generate Optical Model

Point could data should now be animating in the MotionBuilder "Viewer" window.

To Record Data:

  1. MB -> Optical -> Check "Recording"
  2. MB -> Transport Control -> Record (Create new take)
  3. MB -> Transport Control -> Play ( start recording frames)
  4. MB -> Transport Control -> Stop

To Playback Recorded Data:

  1. MB -> Optical -> Uncheck Recording
  2. MB -> Optical -> Uncheck Live
  3. MB -> Transport Control -> Rewind
  4. MB -> Transport Control -> Play

Recorded take data should now begin playing back in the MotionBuilder "Viewer" window.