Crowd Dynamics AI Engine w/ PSO

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Crowd Dynamics AI Engine w/ PSO

• By Keith Ainsworth
• Pd. 5

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Crowd Dynamics AI in C

• Using a game for demonstration
• C with Object Oriented Programming
• SDL for graphical Display (might become OpenGL)

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The AI

• Crowd Dynamics
• Simulates the motion, movement, behavior of
  groups
• Conventional games do it individually
• Simple example A group of people finding a
  target
• Particle Swarm Optimization

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PSO

• A method to optimize the behavior of swarms
• Conventionally used in anthill simulations
• This only optimizes half of my AI engine
• Optimizes the movement calculations
• Does not optimize the communication aspect

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Current Class Structure
PNetwork
World
Person
weight_list
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weight_list

• Looping, array-based, fixed-size container
• 2 lists, one for data, one for weighting in
  summation
• Summation functions, which return the average
  value of the list (taking weighting into
  consideration)
• Used by the PNetwork to pick a direction for a
  person to travel after receiving a bunch of tips
  from the other people

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Pnetwork

• Instantiated with a list of people as the group
• Each time the step() method is called it
• Calls the communicator method of each person
• Adds them all into a weight_list for each person
  (differentiated by the weightings given)
• Instructs the persons to travel in the direction
  of the summation of their weight_list

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Simulation

• Shows Regular Simulation

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Subclassing Structure

• Program Built around base libraries which can be
  subclassed
• Classes include
• World (subclass ngon_world)
• Std_Person (subclasstheta_person, subclass of
  person)

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ngon and ngon_world

• ngon is a class that essentially stores a polygon
  of n sides through the boundary points
• Can be concave, convex, even internally
  intersecting
• ngon_world is a subclass of world, which
  maintains the global variables to the
  simulation
• The subclass allows for obstructions in sight and
  movement of agents in the form of ngons

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R_Limit.hpp

• The simulation wasnt regular in its behavior in
  human/computer interaction
• Different computers Different Difficulties
• This is a rate limiting library
• Utilizes time.h system functions for maximum
  portability and accuracy
• Two methods, queue() and hold(). Queue is called
  before the frames codes, hold is called at the
  end and holds if necessary to maintain a rate.
• Slows a simulation to a rate but cannot speed it
  up to a rate it isnt maintaining.

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ngon_world