摘要: Imagine that you are sitting on a train, standing in queue or walking down the street. You are, like majority of people world, carrying one more mobile computing devices. It could be telephone, portable media player, personal digital assistant (PDA) gaming console (e.g. Nintendo DS, Sony Playstation Portable). Your particular device has 3D graphics capabilities, and have some application – perhaps game, navigation tool computer-aided design (CAD) model needs input. How do provide input to your as intuitively quickly possible, preferably using only hand? And how can while without needing use stable surface such table wall?