Using the Blackboard

You can access blackboard entries through either the BlackboardEntrySelector<T> class or the non-generic BlackboardEntrySelector.


These classes are not available outside the tree, so don't attempt to use them in a MonoBehavior.

The generic BlackboardEntrySelector<T> class will display a field in the inspector that allos you to pick entries and enter a value if you don't want to source it from an entry.

For example, using a public BlackboardEntrySelector<T> field will display an inspector control like this:

The selector

You can enter any float value in the field below, as well as select a blackboard entry using the button to the right of the field.

To access the value (either from the inspector or from a blackboard entry), use the value property on the object like so. In the case of the field above, logging the value will output 2.5.

public BlackboardEntrySelector<float> mySelector;
Debug.Log(mySelector.value) // Writes 2.5

To set the value, simply set the value property. This will only change the underlying value if the selector is referencing a blackboard entry. Setting it otherwise will have no effect.

mySelector.value = 10.0f;
Debug.Log(mySelector.value) // Writes 10.0

You can access the inspectorValue property to change the value as displayed in the editor, though this is not recommended as it will have global effects and will not change a per-tree variable like the blackboard would.

The non generic BlackboardEntrySelector class is a version of the selector in which you can add custom filters to the selector, without specifying a specific type. This version will not display an inspector field like the generic type, however. It will display a simple dropdown (like an enum) which you can then chose the entry to get or set values for.

To add one or more filters, call the AddFilters method on the object. This can be done at any time, though it is only useful in the editor, as that is when the user is selecting a entry.