2-2. Links to Nodes in NIFF
3. Hierarchical Structure of 3D Objects
The objects in 3D games have a hierarchical structure, in many cases . For instance, consider the example illustrated below.
Figure: Object with Hierarchical Structure
This example is an object comprised from 11 objects (hypothetically named Man_Object). As an example, if the Man_Hip object in the above figure is the top level object, the links between the objects would be as shown below.
Figure: Hierarchical Links in an Object
In the case of the above figure, the origin of this Man_Object would be matched to the local coordinate system of the Man_Hip object. However, since Man_Object would normally have its own local coordinate system, and it could be imagined that Man_Hip would be animated in that coordinate system, Man_Object is defined as a NULL object and is linked as shown below.
Figure: Hierarchical Links Utilizing a NULL Object at the Top Level