2009

The Shared Motion Flow Networks feature lets many bipeds use a single
motion-flow network. Therefore, it’s practical to make motion-flow networks
large without taxing your computer's memory.
Delegate-Directed Behavioral Goals
You can give a biped a behavioral goal by associating it with a delegate in the
Crowd system, and then assigning behaviors to the delegate.
For example, in the walkers.max sample, the behavioral goals of each of the
biped's delegates are to:
■ Move toward the sphere using the Seek behavior.
■ Avoid hitting each other using the Avoid behavior.
During a biped crowd simulation, the software attempts to compute the best
motion flow script for each biped member of the crowd that satisfies the
behavioral goals of its associated delegate. In other words:
■ The biped’s crowd delegate defines the behavioral goals of the biped.
■ The possible motions to reach those goals are defined by the biped's motion
flow network.
■ The Crowd object's Solve operation computes the script, or path through
the motion flow network, that best meets the goals of the biped's delegate.
So in the walkers.max sample, the simulation will always choose the best
available walking clip in the network that directs the biped's delegate toward
the sphere. Each biped's script evolves as the crowd "Solve" computes. This is
somewhat like a real-time "game engine" in that the crowd solver’s choice of
the next best clip for a given biped is restricted by that biped's currently active
clip.
Biped Crowd Avoidance, Priority, and Backtracking
Because bipeds in crowds are always following motion flow scripts, the
avoidance behavior for bipeds works differently. Unlike ordinary delegates,
biped delegates can move only along motion flow-scripted paths, so if a
collision takes place, the software will
backtrack on page 4907 to the previous
clip in the current script and find another path. This may take some time to
compute when complex crowd interactions are present since a single backtrack
may not be enough. The computation will explore all paths from a given
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