Initializer

init(toCohereWith:maxDistance:maxAngle:)

Creates a goal whose effect is to make an agent stay near the other agents in a specified group.

Declaration

convenience init(toCohereWith agents: [GKAgent], maxDistance: Float, maxAngle: Float)

Parameters

agents

The agents with whom to stay close.

maxDistance

The maximum distance from other agents required for this goal to take effect.

maxAngle

The maximum angle, in radians, between an affected agent’s velocity and the direction toward the other agents required for this goal to take effect.

Return Value

A new goal object.

Discussion

The agents array can safely include the agent(s) affected by the goal—an agent pursuing this goal will ignore itself in the array. Therefore, you can use a single goal created with this method to cause an entire group of agents to mutually stay near one another.

Changing the maxDistance parameter determines how close to one another agents need to be in order for them to form a group. Changing the maxAngle parameter determines how tightly an agent will turn to maintain cohesion in the group.

You can combine separation, alignment, and cohesion goals to produce “flocking” behaviors in which a group of agents move together.

See Also

Creating Goals for Flocking Behavior

init(toSeparateFrom: [GKAgent], maxDistance: Float, maxAngle: Float)

Creates a goal whose effect is to make an agent maintain the specified distance from other agents in a specified group.

init(toAlignWith: [GKAgent], maxDistance: Float, maxAngle: Float)

Creates a goal whose effect is to make an agent align its orientation with that of other agents in a specified group.