Flocking System BreakdownFlocking Systems | Boids | Geometric Flight | Flocking Behaviour | Collision Avoidance | Velocity Matching | Flock Centring | Examples | Steering Behaviours | Seek and Flee | Pursuit and Evasion | Arrival | Wander | Path Following | Wall Following and Containment
Wander behaviour causes the boid to randomly wander around its environment, without any heuristic influences, other than the usual collision avoidance and flock centring etc. Wandering can be achieved by a number of methods.
Random Steering Force
This method involves generating a random steering force vector (truncated by the boids individual maximum force value) on each time step. Doing this does give the desired result of giving an undetermined final motion path, but the motion is twitchy and not very lifelike. Randomly generating the steering vector gives no relationship between forces from one frame to the next. Therefore a more fluid and continuous steering method is needed.
Spherical Constraint Steering
Rather than change the steering force on each frame, small random displacements are made to it at each step. A virtual sphere is projected slightly in front of the boid, and the new steering vector is constrained so that it must lie somewhere on the surface of that sphere. The vector from the previous time step is also constrained with a smaller sphere, attached to the larger one. This sphere defines the range of motion that the vector can make in the next time step.
This method generates a more interesting flowing motion, as the boid will not make drastic changes in its motion from frame to frame.