BOB JELTES
GAMES PROGRAMMER
Implementing your behavior tree
Now that we’ve made a behavior tree, let’s get it to work in the game.
​Setting up the scene
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Create a capsule game object in the scene
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Add the Behavior Tree Executor component
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Assign the behavior tree you've made to the Behavior field

Override blackboard
Observe that a new section just appeared in the inspector: the blackboard.
This blackboard holds variable overrides. When looking for a variable, the behavior will first search this blackboard for overrides, and then the original blackboard.
This allows us to create unique settings for this agent, or to provide scene references like a game object target.

Creating a target
Let’s create a target cube to put into this variable override.
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Create a 3D cube and call it “Target Cube”
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Select the agent
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Drag the Target Cube into the value slot of the Target variable.

Action!
We are now ready to see the behavior in action.
You should see a green line is drawn between the agent and the target.

Blocking the view
But... not much else is happening.
Let’s place a wall between the agent and the target.

Now the line turns red and is interrupted when the wall obstructs the view!
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And we’re done! You have just created your own behavior tree.