Inspired 3D Character Setup: Basic Building Blocks of Effective Character Creation

Michael Ford and Alan Lehman take us through the step-by-step process of planning the setup of a 3D character. While these steps may sound time consuming the authors assure us it will pay off in the end! The second of several excerpts from the book, Inspired 3D Character Setup.

By Mike Ford and Mike Ford | Friday, July 25, 2003 at 12:00 am

Posted In | Magazines: VFXWorld

[Figure 22] The local rotate and scale pivots values in the Attribute Editor.

It’s important to realize the importance of properly placed pivot points. Also note that while the Insert key moves the rotation and scale pivots together, they are actually stored separately and thus can be modified separately. You may encounter a situation in which you’ll need an object to rotate and scale around a different point.

To view the values of an object’s pivots, select your sphere and open the Attribute Editor (see Figure 22).
When the Transform node is selected, the pivot information appears in the second window shade, under the major transform attributes. Here you can see the local and world space values of both the rotate and scale pivots.
In the Pivots window shade, check both Display Rotate Pivot and Display Scale Pivot. In any view, you should now see both pivots right on top of one another.
Modify the values of the local space scale pivot back to 0, 0, 0 in the Attribute Editor. You should see the scale pivot move back to the origin.
Select the Scale tool or press the “R” key, and notice that your scale pivot is now in a different location than your rotate pivot. Scale and rotate the sphere to see the difference (see Figure 23).

When you change pivot points, you dramatically alter the way in which the object will behave. A good point to remember is that pivots must be kept in the same locations once a character is created in its default position. Animation curves will not properly copy over from one character rig to the next if there are changes to the character’s pivot locations.

[Figure 23] Composite image of scale and rotate pivots in different locations.

Hierarchy — Parent/Child Relationships
It is crucial that you understand how hierarchy influences the movement and structure of the character that you build. As we learned in the Computer Graphics Primer, a hierarchy is a relationship of nodes to other nodes described in terms of parent, child and sibling.

Nodes
Every object in a scene is referred to as a node, including lights, cameras, geometry, materials, animation curves, constraints, and any other type of object you can create. Nodes with a presence in 3D space (locators, polygons, cameras and so on) are broken into two parts, called transform nodes and shape nodes.