Main page → OptiTrack Unity Plugin
Notes on HMD Integration
From Motive, the tracking data can be streamed in real-time either from a live capture (Live Mode) or recorded data (Edit Mode). The streaming settings are configured by modifying the Streaming Settings. NatNet streaming must enabled and the correct IP address must be set.
Open the Streaming Settings in Motive and configure the settings below:
While in the Unity project, double-click on the plugin unitypackage file and import the plugin assets into the project. When the package has been successfully imported, the following contents will be available within the project:
In order to receive tracking data from a server application (e.g. Motive), a client object must be set up. The OptitrackStreamingClient.cs script can be attached to any object to stream data relative to that object. Typically, this script is attached to an empty object or loaded in using the "Client - OptiTrack" prefab object in the Assets/Optitrack/Prefabs folder.
By integrating with Unity's animation system, Mecanim, the Unity3D plugin allows Motive to stream full body skeleton data. The skeleton tracking data from Motive is streamed out as hierarchical bone segment orientations, and this data is fed into the Unity's Mecanim system which allows animating characters with different proportions.
Note: At the time of writing, Mecanim does not support explicit goals for inverse kinematics end-effectors when using real-time retargeting. In addition, you may observe a difference in the overall scale of the position data between the retargeted skeletal animations and streamed rigid bodies. These two limitations may lead to inconsistencies with actors interacting with rigid body props, and will hopefully be addressed in a future version of the integration.
OptiTrack motion capture systems can be used to track head mounted displays (HMD) and integrate the tracking data into Unity for unique VR applications. For instructions on integrating HMD tracking data into Unreal Engine, please refer to the corresponding page Unity: HMD Setup.
At the time of writing, the following HMDs are supported:
When setting up multiplayer games with wireless clients, it is more beneficial for each client to make direct connection to both the tracking-server (Motive) and the game-server, rather than rebroadcasting the streamed tracking data through the game-server. Then, any of the game related actions that interacts with the tracking data can be processed on the game-server, and this server can send out the corresponding updates to the wireless clients. This allows the wireless clients to only receive both the tracking data or updates without having to send back any information; in other words, minimizing the number of data transfers needed. If wireless clients are sending data there will be a minimum of two transfers on the wireless network, and each transfer of data through wireless network is at risk of latency or lost packets.