This is a simulation of gravitational attraction between lots of 'stars'.
The Barnes-Hut Algorithm is used to efficiently calculate the forces acting on each star.
Arrow Keys: Slow pan.
=: Zoom in.
-: Zoom out.
0: Zoom standard.
Home: Return to original view.
b: Toggle bounding box rendering.
f: Toggle brute-force mode. Stars turn blue when this mode is active, and gravitational attraction is calculated for every single pair of stars. The Barnes-Hut grid is not updated.
g: Toggle Barnes-Hut grid rendering.
p: Pause/unpause simulation.
t: Toggle star trail rendering.