: Results with no lookahead (left) and lookahead (right) for 2 demo scenarios. Crossing: (Top) shows two groups of agents heading to diametrically opposite ends t = 10s, note how bigger group parts to allow smaller group through with lookahead. Circle: (Bottom) shows agents on the edge of a circle heading to diametrically opposite points t = 40s, note significantly improved progress with lookahead Local collision avoidance algorithms in crowd simulation often ignore agents beyond a neighborhood of a certain size. This cutoff can result in sharp changes in trajectory when large groups of agents enter or exit these neighborhoods. In this work, we exploit the insight that exact collision avoidance is not necessary between agents at such large distances, and propose a novel algorithm for extending existing collision avoidance algorithms to perform approximate, long-range collision avoidance. Our formulation performs long-range collision avoidance for distant agent groups to efficiently compute trajectories that are smoother than those obtained with state-of-the-art techniques and at faster rates. Another issue often sidestepped in existing work is that discrete and continuum collision avoidance algorithms have different regions of applicability. For example, low-density crowds cannot be modeled as a continuum, while high-density crowds can be expensive to model using discrete methods. We formulate a hybrid technique for crowd simulation which can accurately and efficiently simulate crowds at any density with seamless transitions between contin- * golas@cs.unc.edu † narain@eecs.berkeley.edu ‡ lin@cs.unc.edu uum and discrete representations. Our approach blends results from continuum and discrete algorithms, based on local density and velocity variance. In addition to being robust across a variety of group scenarios, it is also highly efficient, running at interactive rates for thousands of agents on portable systems.
To robustly model multiple densities, REF proposed a hybrid scheme for simulating high-density and low-density crowds with seamless transitions.
Hybrid long-range collision avoidance for crowd simulation
I3D '13
Computer Science Medicine