Overview

In the previous chapter, you learned about VIZ s geometry primitives and how they can be shaped by parameters and modifiers into an infinite variety of forms. In this chapter, you ll continue your introduction to primitives with an exploration of splines. Splines are a type of primitive, and they are classified as shapes in VIZ. In a way, shapes are even more primitive than the geometry primitives you looked at in Chapter 2. You can create more varied forms with splines than you can with the geometry primitives, but they require a bit more work to use.

In general, you can think of splines as objects composed of straight-line or curved-line segments. Splines can be two- or three-dimensional, but unlike geometry, splines do not define surface areas or volumes. Splines are defined only along their edge segments. Strictly speaking, a spline is a line or curve whose shape is controlled by its vertices, which are the points along the spline. Bezier splines are a type of spline that includes features, called handles, for controlling the curvature as it enters or exits each vertex. Splines are initially created as two-dimensional objects (with the exception of the Helix spline primitive, which is a line that curves in 3D space like a spring or a DNA strand). Like the standard primitives in VIZ, most splines are parametric; that is, they can be modified using parameters like the Width and Length parameters of the Box standard primitive. All the splines can...