Motion levels of detail for real-time virtual worlds

Animating numerous human-like figures in large virtual spaces makes it difficult to provide users with an interactive simulation rate. The problems mainly consist in the large number of walkers required to simulate realistic virtual spaces and in the accuracy of the model needed to account for complex environments. We propose a new approach of model design in order to minimize the computation cost according to the kind of simulation and environment; A low-cost simplified walking model is designed for flat-ground while a more complex one is proposed for complex terrains. We also describe how and when the transitions between these models occur while ensuring a visually realistic motion. The results show that using simulation levels of detail is specially suitable for simulations in large virtual spaces and makes it possible to visualize realistic motions of walkers with a controlled computation cost.