Write-Once, Transpile-Everywhere: Re-using Motion Controllers of Virtual Humans Across Multiple Game Engines

  • Fabrizio NunnariEmail author
  • Alexis Heloir
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10850)


Transpilation allows to write code once and re-use it across multiple runtime environments. In this paper, we propose a software development practice to implement once the motion controllers of virtual humans and re-use the implementation in multiple game engines. In a case study, three common human behaviors – blinking, text-to-speech, and eye-gaze – were developed in the Haxe programming language and deployed in the free, open-source Blender Game Engine and the commercial Unity engine. Performance tests show that transpiled code executes within 67% faster to 127% slower with respect to an implementation manually written in the game engine target languages.


Virtual humans Motion controller Software architecture Transpilation Haxe 



The authors wish to thank our student Timo Gühring for his precious help in the development and translation of the TTS and the eye-gaze modules. We also thank Kiarash Tamaddon for the Unity project setup.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.DFKI-MMCI, SLSI groupSaarbrückenGermany
  2. 2.LAMIH UMR CNRS/UVHC 8201ValenciennesFrance

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