About Trigger Zones

A trigger zone can detect a single actor or a collection of actors.

With the Object Filter property, you can define which actor or collection of actors must be detected by the trigger zone. For more information, see Trigger Zones Properties.

A trigger zone is also a scenario object. By default, it is hidden when you play an experience. You can customize the visibility of a trigger zone by modifying the default preferences. For more information, see Customizing Preferences.

There are several types of trigger zones: cube, sphere, etc. You can define the size of each type.

For example, you can use a trigger zone to activate the door opening when an actor enters the volume.

Interactions between actors of a scene are propagated to parents actors. An interaction between any exposed subactor of the scene and a trigger zone also applies to its parent actor.

Conditions for propagating interactions to a parent actor are described in the following table:

Interaction Type	Conditions for Propagation
Enter	A parent actor enters a trigger zone if one of the following conditions is met: Its own geometry enters the trigger zone* Any of its exposed subactors enters the trigger zone.
Inclusion	A parent actor is included a trigger zone if all the following conditions are met: Its own geometry is included in the trigger zone* All of its exposed subactors are included in the trigger zone.
Exit	A parent actor leaves a trigger zone if all the following conditions are met: Its own geometry leaves the trigger zone* All of its exposed subactors leave the trigger zone.
End Inclusion	A parent actor is no longer entirely included in a trigger zone if one of the following conditions is met: Its own geometry is no longer entirely included the trigger zone* Any of its exposed subactors is no longer entirely included in the trigger zone.

^*: the geometry is unexposed under a subactor.