A trio of IT researchers affiliated with Facebook have created a new method to turn a video of an individual performing a series of actions (e.g. a dance) into a 3D 'game character'. This character - and its associated movements - can then be transposed onto a new background. The researchers assert that this background could interact with said character.
https://www.notebookcheck.net/Facebook-researchers-develop-AI-method-to-convert-videos-of-people-into-playable-game-characters.418589.0.html