Emergent Motion

BOIDS.JS

A high-performance flocking library for the modern web. Simulate complex collective behavior with algebraic precision.

Scroll
Origins & Evolution

The Legacy of
Craig Reynolds

In 1986, Craig Reynolds revolutionized computer animation by introducing the world to "Boids", an artificial life program that simulated the flocking behavior of birds.

Instead of complex global control, Reynolds proved that group intelligence could emerge from three simple local rules: Separation, Alignment, and Cohesion.

BoidsJS pays homage to this groundbreaking discovery, bringing the same mathematical elegance to the modern web with optimizations for real-time interactivity and scalability.

Rule 01

Separation

Steer to avoid crowding local flockmates.

Rule 02

Alignment

Steer towards the average heading of flockmates.

Rule 03

Cohesion

Steer to move towards the average position of flockmates.

The Optimal Strategy

The Power of Seven

While Reynolds defined the rules, researchers at Princeton University discovered how birds actually apply them. By studying starling murmurations, they found that each bird tracks exactly their seven nearest neighbors.

This topological interaction, rather than a fixed radius, provides the most robust balance between individual effort and group cohesion, allowing flocks to maintain their structure regardless of density.

BoidsJS implements this "7-Nearest" optimization, providing a highly performant alternative to classic O(n²) spatial sensing.

Core Logic

Three Distinct
Movements

BoidsJS provides native support for multiple steering behaviors, allowing you to choose the right balance between performance, style, and fidelity.

The Gold Standard

Classic Reynolds

The original 1986 implementation using global sensing and O(n²) complexity for high-fidelity flocking behavior.

Performance Driven

7-Nearest Optimized

A modern optimization that limits perception to the 7 closest neighbors, reducing computational load and better matching natural flocking behavior.

Vector-Based Guidance

Dynamic Flow Fields

Boids follow an underlying noise map that evolves over time, creating organic, wind-like movement patterns.