1. Dept. of Pervasive Computing, Tampere Univ. of Technology, Tampere, Finland
2. Mads Clausen Institute, Univ. of Southern Denmark, Kolding, Denmark
3. The Mixed Reality Laboratory, School of Computer Science, University of Nottingham, UK
4. Game Research Lab, University of Tampere, Tampere, Finland
5. Philips Lighting Research, Eindhoven, The Netherlands