Approximate, incremental nearest-neighbour algorithm for moving bodies

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Here\'s a problem I\'ve been playing with.

Answer 1

When the distance that an Actor moves in a given timestep exceeds the distance to its furthest known neighbour, resample all neighbours.

Another trigger: when the distance an Actor has moved since the last resample exceeds the distance to the furthest known neighbour, resample.

Trivial optimisation goes well here, if there is a hierarchial spatial index, search for a node containing both a) a sphere of radius equal to the jump size, and b) at least N Actors.