Trigger volumes
CTriggerVolumeBox components define a 3D bounding box that triggers an event, much like script triggers. The difference is that a script trigger is a separate object, while a trigger volume is a component of the object it triggers.
The box is drawn only while the component is selected, or when the Trigger Volumes camera layer is enabled.

Edit a trigger volume
Section titled “Edit a trigger volume”- Move, rotate and scale it using the component panel on the right or using gizmos.