User Guide

This section illustrates how to create the various Behavior Tree assets within Unity.

Behavior Trees are essentially the Is processor and can make decisions and execute various branches based on the outcome of those decisions. Now an example of creating a simple bot will be shown:

Creating Behavior Tree

Behavior Trees are essentially the AI's processor and can make decisions and execute various branches based on the outcome of those decisions.

Click on the Assets tab, then select Create/Renowned Games/Behavior Tree

Creating Behavior Tree

Also you can right-click in the Project Window, then select Create/Renowned Games/Behavior Tree

The new Behavior Tree asset will be added to the Project Window which you can rename to your desired name.

Behavior Tree Name

Creating Random Position Task

To create Random Position node, we need to go to the desired Behavior tree and right-click the context menu.

Click on Create Node/Tasks/NavMesh/Random Position

To save the position value we need to create Blackboard.

Creating Blackboard

Click on the Assets tab, then select Create/Renowned Games/Blackboard

Creating Blackboard

Also you can right-click in the Project Window, then select Create/Renowned Games/Blackboard

The new Blackboard asset will be added to the Project Window which you can rename to your desired name.

Blackboard name

Connecting Blackboard in Behavior Tree

To connect Blackboard to the Behavior Tree, click on the Behavior Tree we need and drag the desired Blackboard into the Behavior Tree inspector window where the Blackboard field will be.

Behavior Tree Inspector

You can also add it by clicking on the field with blackboard and select it from all the blackboards in the project.

Connecting Blackboard in Behavior Tree

Creating Keys for Blackboard

In the Blackboard, we create a Key with the vector type and call it position.

To create a Key, click on the New Key tab.

Creating new Key

In the window that opens, select the Key type.

Selecting Key types

An example of how it should turn out:

Creating position Key

In the Random Position node inspector window, specify your new Key.

Assigning new Key in Task

Creating Move To Task

So that our character can approach the generated position, we will create Move To node.

To create Move To node, we need to go to the desired Behavior tree and right-click the context menu.

Click on Create Node/Tasks/NavMesh/Move To

Creating Move To Task

In the Move To node inspector window, specify position Key.

Assigning new Key in Task

Creating Wait Task

To create a small delay, we will create Wait node.

To create Wait, we need to go to the desired Behavior tree and right-click the context menu.

Click on Create Node/Tasks/Common/Wait

Creating Wait Task

As in Move To Task, we add the position Key

In field Wait time specify 3 seconds.

Filling Wait Time field

If you don't want to create a Key in the Blackboard, then you can click on the flag next to the field and enter your fixed value.

Creating Sequencer

Now our tree looks like this.

To link our years we need to add Sequencer. Executes child nodes alternately.

To create Sequencer, we need to go to the desired Behavior tree and right-click the context menu.

Click on Create Node/Tasks/Composites/Sequencer

Creating Sequencer

Linking Nodes

To link a node, you must pull the connection from the top or bottom of the node (indicated by a circle) to the center of another node.

Link example

Connecting nodes in Behavior Trees only work by connecting an output to an input (you cannot connect from an input to an output).

We connect the remaining nodes in the same way:

Links example

Connecting Behavior Tree with GameObject

To connect Behavior Tree to GameObject, we need to add a component to it Behavior Runner.

To do this, go to the inspector window of the necessary GameObject.

Clicks Add Component and searches Behavior Runner.

In the Behavior Runner field, connect our created Behavior Tree.

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