01 / ALIGNMENT
Go with the flow.
Steer toward your neighbors’ average direction. Turn alignment down to see the flock lose its shared heading.
Preparing your flock…
A free-flowing flock. Try guiding it with Attract.
Your moving world
RunningHold or drag to guide the flock. Choose Obstacle to add or remove a rock; Inspect to follow one boid.
- Boids
- 120
- Moving together
- —
- Obstacles
- 0
Choose Inspect, then tap a boid to reveal its local world.
Keyboard controls
Tab to the canvas. Arrow keys move the tool marker. Enter uses the selected tool; hold Enter to attract or repel. Escape releases the target. Space pauses or resumes. Obstacles toggle on or off near the marker, up to eight rocks.
Your experimentTune the flock
Change one rule at a time. The flock responds immediately.
Restart replays this starting flock with your current settings. New flock changes the starting arrangement. Changing scenes starts a new experiment.
No leader. Just neighbors.
Three rules make a flock.
Each boid steers using the agents close to it. A group pattern emerges from those local decisions.
02 / COHESION
Stay connected.
Steer toward the center of nearby boids. Turn cohesion down and watch how easily groups drift apart.
03 / SEPARATION
Keep some space.
Steer away from close neighbors. Increase separation to make the group spread out around each boid.
Try an experiment
What makes them move together?
- Remove a rule. Set alignment to zero. Wait a moment, then restore it. Does the group recover its direction?
- Split the flow. Place a few obstacles. Use Attract to guide the flock past them. Then choose School to explore its stronger alignment.
- Follow one decision. Pause, turn on neighbors & forces, and Step. Compare the three colored steering arrows as nearby boids change.
Read the view: “Moving together” measures how closely the flock’s headings agree, from 0% (mixed directions) to 100% (one direction). It does not measure how close together they are. In Inspect, the circle marks the neighborhood. Teal, violet, and coral arrows show alignment, cohesion, and separation; the white arrow shows their combined steering with other influences.
This is a two-dimensional learning model inspired by Craig Reynolds’ original Boids work, developed in 1986. It illustrates collective motion rather than predicting a particular animal species. Motion pauses when the page is hidden. Reload starts a fresh session.
Langton’s Ant
Ring of Fire