ABSTRACT
A joint is a transform node, and like any transform node it has a particular point in space where it is located. Each joint has a World position coordinate. But joints dier from transform nodes in that they are a special type of object and have extra properties that are used when constructing “skeletons,” which are hierarchical construction of multiple joints that are used to dene character motion using rotations and translations (and sometimes even scale). ese special properties are there in order to assist the rigger and animator in constructing rigs that conform to the basic mechanics of movement, which are called “kinematics.” Figure 3.1 illustrates what a single joint looks like in Maya, which is simply three hoops together that indicate the direction of the “joint orient” (which we’ll talk about in a moment). Figure 3.2 illustrates what joints look like when parented to one another, which appears like a pyramidal structure, with the large end of the pyramid beginning at the parent and the small end terminating at the child.
