动态场景的可见性计算对于大规模场景的实时渲染具有重要意义,其中运动中的大规模群体更给可见性计算带来了很大的开销,针对大规模动态群体在建筑物场景内部运动的情况,提出一种与场景结合的动态群体可见性计算方法,在预处理时,根据个体在不同仿真时刻的位置,将其绑定到相应的场景节点中;在实时绘制时,结合场景的可见性判断结果对动态群体中的个体进行可见性判断,实验结果表明,该方法能高效地剔除动态群体中的不可见个体,使大规模动态场景的实时绘制效率得到明显提高。
Visibility calculation of dynamic scenes is a key issue for real-time rendering of large scale scenes, but a time consuming process, in particular, for the visibility computation of large dynamic crowds. In this paper, we present an efficient visibility culling method for dynamic crowds moving inside buildings. During the preprocessing stage, the space of a building is organized as a binary tree, our method subdivides the entire simulation time period into discrete intervals and assumes that at each time interval, any individual of the crowd remains in the same subspace of one scene node while accounting for his/her movement, therefore can be bound to that node. During the rendering stage, the visibility of a scene node can be used as an over-estimate of the visibility of all individuals bound to that node regarding the specified time interval. Experiments show that our method can efficiently cull invisible individuals of dynamic crowds within complex buildings, thus greatly accelerate the visibility calculation process.