MotionRiver Setup

Setup the Open source MotionRiver tool for Optitrack Motive to stream mocap over the internet to Unreal.
N.B I’m using Unreal version 4.26 Run Motive, play a mocap file or have a live performer move around.
Run the MotionRiver Source App then the MotionRiver Server App. In Unreal check the MotionRiver and LiveLink plugins are loaded.
(MotionRiver Plugin goes in Project folder)
Open LiveLink window, add a MotionRiver Source, use either local IP of your mocap computer (MotionRiver Server machine) or the external IP if you have a fixed IP address.
(You will need to open port 60000 on your router for external mocap streaming, with the port open for the IP address of the computer that is running the MotionRiver server.)
Select the subject and map the corresponding bone names to the skeleton of your character.
Save your LiveLink preset for later use.
Make an Animation Blueprint and use a Live Link Pose as the input with your Subject name.
Make a character blueprint and use your AnimBP.
Place the character in the level and hit Play to see it move.
In project settings, you can set Live Link to load your preset with the project.

To package your project will need to be a C++ project. If it is not then you need to convert it.
To do this, download Visual Studio 2019 and set it up for Unreal. Guide here:…​
In the editor go to File / New c++ class.
Just leave none selected and click okay with the class name at its default and it will convert your project and open Visual Studio.
When that is done, close the project and in Visual Studio, from the menu at the top go to Build / Build Solution.
When that is done reopen the project and it should package.

Now the project will be good to package and send out
(however if the LiveLink preset is not loaded with the project settings (or in code) and the IP address is not external, then it won’t find the streaming mocap)

Credits: Performer: Harry Alexander
Funded by UKRI, developed by Cooperative Innovations for THAYAHT with support from the University of Portsmouth.
Part of the DAZZLE project
Watch out for the upcoming VICON version!!
Github link for the code to come!!

Also note Motive settings below for streaming. I’m using these settings in Motive 2.3. It seems as if there is a bug in Motive 3.0 – the standard skeleton has extra bones added that don’t get picked up correctly by the LiveLink plugging (07/11/21)

Motive 2.3 Settings for streaming to MotionRiver