Flow Field Pathfinding

Over the years people have asked me about "Flow field pathfinding". I felt like the early papers about it conflated the flow fields with hierarchical pathfinding, but I wasn't sure, and I didn't want to write about it until I was sure. Flow fields are a vector field that tells agents from any location what direction to move to find a single destination. Optionally, agents that are in between locations on the pathfinding graph can interpolate between the vectors in the flow field. Optionally, a hierarchy of coarse and fine stepped fields can speed up pathfinding. The graph-based pathfinding algorithms I cover on my A* page output both distance fields and flow fields, in the cost so far and came from outputs. I still update my pathfinding pages that I started in 1997, and I still update my interactive pathfinding pages that I started in 2014.