Pathfinding steering behaviour

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Pathfinding steering behaviour

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Steering behaviour

• Suggested reading Reynolds, C. W. Steering
  Behaviors For Autonomous Characters. Proceedings
  of Game Developers Conference 1999, San Jose,
  California. Miller Freeman Game Group, San
  Francisco, California. Pages 763-782. 1999.

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Steering behaviour

Action selection strategy, goals, planning,
pathfinding
Steering path determination
Locomotion animation, articulation
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Steering behaviour

• Taxonomy
• Seek pursuit of static target.
• Locate target
• Turn towards location of target
• Move (possibly at full speed)
• Loop to 1.
• Moth around light bulb behaviour

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Steering behaviour

• Taxonomy
• Flee inverse of Seek.
• Locate target
• Turn opposite to location of target
• Move (possibly at full speed)
• Loop to 1.

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Steering behaviour

• Taxonomy
• Pursuit similar to Seek, but target is moving.
• Locate target
• Estimate target future location (ideally at the
  moment of interception, which however is unknown)
• Turn towards future location of target
• Move (possibly at full speed)
• Loop to 1.

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Steering behaviour

• Taxonomy
• Evasion inverse of Pursuit.
• Locate target
• Estimate target movement direction
• Move away from target (possibly at full speed)
• Loop to 1.

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Steering behaviour

• Taxonomy
• Arrival similar to Seek, but speed gradually
  decreases as agent approaches target.

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Steering behaviour

• Taxonomy
• Obstacle avoidance never get closer to obstacles
  than a given offset.

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Steering behaviour

• Taxonomy
• Collision avoidance never get closer to
  obstacles and other moving agents than a given
  offset.

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Steering behaviour

• Taxonomy
• Wander random path.

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Steering behaviour

• Taxonomy
• Path following move forward following e.g. a
  line.

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Steering behaviour

• Taxonomy
• Flow fied following move forward following e.g.
  a vector field.

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Steering behaviour

• Taxonomy
• Group behaviour behaviour that is co-dependent
  on other agents behaviour.
• Separation agent makes sure it is always a
  certain distance apart from all other agents.
• Cohesion agent makes sure it is always within a
  certain distance from at least one other agent.
• Alignment agent identifies closest moving agent
  and goes the same direction and/or speed as that
  agent.

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Steering behaviour

• Taxonomy
• Group behaviour behaviour that is co-dependent
  on other agents behaviour.
• Flocking complex combination of separation,
  cohesion and alignment to simulate natural
  flocking behaviour.
• Leader following special case of flocking in
  which agents are choreographed to follow a leader.

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Steering behaviour

• Previous behaviours can be combined to produce
  complex group behaviour.

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Assignment 3

• Steering behaviour program agents with a
  combination of
• Wander, obstacle avoidance and collision
  avoidance for agent whose ID is 0, who can also
  keep saying permanently a word to help other
  agents locate it.
• Pursuit, obstacle avoidance, separation and
  cohesion for all other agents.