The Flock Modifier is a modifier object for the good old standard particle system in Cinema 4D. It allows to easily apply the behavior of flocks, swarms or schools to the particles.
The modifier uses a distributed behavioral model, as described by Craig Reynolds in his 1987 SIGGRAPH paper "Flocks, Herds, and Schools: A Distributed Behavioral Model". Several of the classic "Reynolds Rules" are implemented. Each particle will...
- ...keep a minimum distance to its neighbors
- ...try to stay in the center of the flock
- ...chase a target
- ...match the velocity and travel direction of its flockmates
- ...obey a certain minimum / maximum speed limit
- ...avoid collision with geometry
- ...fly level / avoid steep rising or falling
- ...apply a certain randomness to its movement
This plugin demonstrates the following C4D API aspects:
- Particle modifier plugins, derived from
class ObjectData - Working with the C4D standard particle system (which is not as lame as it sounds) using
ObjectData::ModifyParticle() - Ray intersections with
class GeRayCollider - Simple viewport drawing
- Aligning matrices to trajectories and directions