Adaptive User-Centric Experiences in Virtual Environments: Levels of Interactions - Panzoli, David; Peters, C; Dunwell, Ian; Sanchez, S, S; Petridis, Panagiotis; Protopsaltis, Aristidis; Scesa, V; De Freitas, Sara (The 13th International Conference on Computer Graphics and Artificial Intelligence (3IA, 2010)