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Table Of Contents
Selecting the parent node at the top of the hierarchy also selects the items
contained in the hierarchy below. Selecting a child node lower in the hierarchy
selects any child nodes that are lower in the hierarchy.
Hierarchies allow you to create complex structures with relationships between
components. For example, when you animate a hierarchical model, you simply
need to select and move the parent node of the hierarchy and the rest of the
model (child nodes) also moves.
Regardless of whether you decide to animate the mechanical arm using FK or
IK, or a combination of both methods on the same model, the best approach
involves making the mechanical arm model into a hierarchical structure.
Creating a hierarchy for the mechanical arm ensures that:
Components of the hierarchy can be rotated as if they were one unit. A
common pivot point is created at the parent node level. This allows the
separate components to rotate as one unit based on their membership in
the hierarchy. For example, if the mechanical arms base (parent node) is
rotated, anything lower down the hierarchy, for example, the mechanical
arm which is constructed of child nodes, will also rotate because of its
membership and position in the hierarchy.
When a particular segment of the model is posed and keyframed, the
components that are lower in the hierarchy are also posed and keyframed.
Viewing hierarchies using the Hypergraph
In the following steps, you use the Hypergraph to view the hierarchy for the
mechanical arm. The Hypergraph is a scene management editor that presents
a graphical view of the scene hierarchy. It allows you to more easily create,
understand, and manage the hierarchy of objects and nodes in your scene.
To view hierarchies using the Hypergraph
1 From the perspective views panel menu, select Panels > Layouts > Two
Panes Stacked.
The workspace displays two panels stacked on top of each other with an
identical perspective view of the scene.
2 In the lower panel, select Panels > Hypergraph Panel > Hypergraph
Hierarchy.
The lower panel displays the Hypergraph.
Viewing hierarchies using the Hypergraph | 265