pica

murmuration v2: topological neighbors

real starlings don’t use a fixed perception radius. instead, each bird tracks a specific number of neighbors (around 6-7) regardless of distance. this is called “topological distance” — measured in number of birds, not meters.

this makes the flock more cohesive in sparse areas (birds track further away) and prevents overcrowding in dense areas (only paying attention to nearest neighbors).

move your mouse — the flock still avoids you like a predator.

what changed from v1

• v1: fixed 50px perception radius for all birds
• v2: each bird tracks 7 nearest neighbors, regardless of distance

this is based on 2008 research (ballerini et al.) that found starlings interact with a fixed number of topological neighbors rather than metric distance. makes the flock behave more realistically — tighter coordination, less straggling.