First, you'll want to follow the instructions below to set up the data streaming settings in Motive. Once this is configured, Motive will be broadcasting tracking data onto a designated network interface where client applications can receive them.
Open the Data Streaming Pane in Motive's Settings window and set the following settings:
To get started, drag the OptiTrack Skeleton plugin from the Motion Builder Asset Browser tab > Devices into the Viewer window. This will create a dropdown menu called I/O Devices in the Navigator tab. Click the + button next to I/O Devices and select OptiTrack Skeleton. This will populate the plugin's settings tab if it hasn't already auto-populated from the drag and drop step from earlier.
Once the above settings are input appropriately, you'll want to click the box next to Online. This indicate whether or not Motive is successfully streaming to MotionBuilder.
The Skeleton Device plugin uses model binding to map Motive skeleton data to MotionBuilder animation nodes. There can be multiple model binding templates in a MotionBuilder scene. The active model binding is indicated in the model binding combo box on the Device tab.
The MotionBuilder plugin monitors the tracking model list it is receiving from the server (e.g. Motive). If it detects a change in the tracking model list, it will automatically update the current MotionBuilder skeleton list to match, creating new skeletons when necessary, or re-connecting to existing skeletons where possible, based upon the skeleton/tracking model name. It will not remove existing MotionBuilder skeletons.
If the plugin is unable to automatically update the model template, you must update your model binding in the Skeleton Device plugin to a model binding that matches the tracked model. To do this:
If the active model list in Motive changes, the MotionBuilder Plugin Device Information panel will show Tracking Models Changed and the Info Tab will indicate whether a suitable template was found.
The Auto-Characterize button on the Skeleton Device will automatically characterize each generated skeleton based on the scaled neutral pose of the performer. It will create a new MotionBuilder character with the same name as the mocap performer/MotionBuilder skeleton pairing. The advantages of using this approach are:
When using Auto-Characterize, you must be streaming from Motive before enabling the OptiTrack Skeleton device for correct pose scale detection. Otherwise, when the auto-characterized skeleton is used as the input to a target character, the character may incorrectly scale. This does not apply if the target character’s Match Source or Actor Space Compensation is adjusted.
Auto-Characterize is an optional feature and is not required for character retargeting.
Configure Motive for Streaming Data
Be sure to configure any Firewall software first (either disable or permit MotionBuilder as an exception).
Create an OptiTrack Skeleton device
Connect Skeleton Device to Motive
Create a Motive to MoBu skeleton binding
Begin streaming marker data
The OptiTrack Skeleton device can record optical data to the current MotionBuilder take. Please refer to the Autodesk MotionBuilder: OptiTrack Optical Plugin page for steps on how to record from devices into MotionBuilder.
The OptiTrack Skeleton device can be used show live data or blend live data with a recorded take. Please refer to Playing Back Recorded Data section for steps on how to record from devices into MotionBuilder.
One approach to quickly stream Motive skeletons onto MotionBuilder characters:
Note for saving into FBX
When a MoBu character is associated with a streamed skeleton and it is set to Active, only the mapped segments of the character will be saved in exported FBX files, and segments that were not mapped will not be saved. In order to fully preserve the character including unassociated segments, uncheck Active (from Step 8) before saving out the FBX file.