Decorator, also known as conditionals in other Behavior Tree systems, are attached to either a Composite or a Task node and define whether or not a branch in the tree, or even a single node, can be executed.

Built-In Decorators

In Blackboard Based Conditions the node will check to see if a value is set on the given Blackboard Key.

With Notify Observer it is possible to choose when changes are notified to the decorator:

• On Result Change: Reevaluate only when the condition has changed.
• On Value Change: Reevaluate only when the observed Blackboard Key changes.

With Observer Aborts it is possible to specify the mode in which the decorator reacts to the aformentioned changes:

• **None: ****Do not abort anything.
• **Self: ****Abort self and any sub-trees running under this node.
• Lower Priority: Abort any nodes to the right of this node.
• Both: Abort self, any sub-trees running under this node, and any nodes to the right of this node.

The Loop decorator will make the node it is applied to loop.

The user can specify the number of loops or set it to be infinite.

The IsAtLocation decorator checks if the actor is in at a certain distance or less from the object described in a blackboard key.

With Acceptable Radius it is possible to specify a value, at it can also be parametrized by setting the binding in Parametrized Acceptable Radius.