9.5.2

1126 • CHAPTER 22
XPRESSO EDITOR • 1127
Hierarchy
Paths enable you to access groups of objects at any position in the hierarchy. In this example, the
Hierarchy node outputs the three Sphere objects.
This node rst locates a position in an object hierarchy, as dened by a Reference Path and a Start
Path. From this position in the hierarchy, the node then follows a repeatable Iteration Path and outputs
all of the objects it meets as it travels along the iteration path. The node is controlled primarily in the
Attribute manager.
Reference Mode
Use Start Position
To reference an element relative to the object that owns the XPresso tag, use either this mode or the
more advanced Relative Reference mode. For example, to reference the element that is three positions
before the object that owns the tag, set Reference Mode to Use Start Position, set Start Position to
Predecessor On This Level and set Start Distance to 3. The Use First Position mode also enables you to
reference the rst or last object in the scene.
Absolute Reference
This mode references the object that is displayed in the Reference box. If you want to use the
expression in several places in your scene, avoid using the Absolute Reference mode, otherwise you’ll
need to change the referencing of the objects each time.