TouchEngine allows other software packages to load TouchDesigner components from .tox files, process them, and pass data back and forth.
The SDK, including documentation and an example project for Windows are available here:
and for macOS:
There is no licensing fee or royalty required to make use of TouchEngine within your software package. It can be included in any software package for free, and the feature becomes enabled by the end-user installing a paid TouchDesigner or TouchPlayer license on the machine (Educational, Commercial, or Pro, see Licensing for details). Additionally TouchDesigner or TouchPlayer must be installed on the system to use TouchEngine.
In TouchDesigner the Engine COMP works with any license including Non-Commercial licenses.
Engine COMP - The Engine COMP is a native component in TouchDesigner that loads .tox component files into a project yet runs them on a separate TouchEngine process.
Unreal Engine Plugin - The TouchEngine For UE Plugin allows Unreal Engine users and developers to load TouchDesigner .tox files, process them, and pass data back and forth from within Unreal Engine.