206 chapter 6 ■ ZSpheres
Introducing ZSpheres
ZSpheres are accessed like any other tool in ZBrush: from the Tool menu. The ZSphere icon
is located under the Startup 3D Meshes section of the Tool menu (Figure 6.2). Clicking the
ZSphere icon allows you to draw a ZSphere on the canvas.
When a ZSphere is drawn on the canvas, you must enter Edit mode as with any other
ZTool. Doing so establishes this first sphere as the root of your ZSphere chain. Any other
spheres you draw will have to connect to this first sphere. As you work, you can move this
sphere but you can never delete it—you can delete other ZSpheres at will, however. The chain
created with a ZSphere will be converted to an adaptive skin to make a polygon mesh. An
adaptive skin is a mesh generated by skinning a ZSphere chain based on the properties set
for the spheres. We’ll cover adaptive skins later in this chapter, but for now think of them
as a polygon sock stretched over the ZSphere chain
you created (Figure 6.3). There is a second skinning
method called unified skin, but we won’t use this for
the ZSphere model. Unified skins come into use
for ZSketch meshes in Chapter 10, “ZSketch and
Hard-Surface Brushes.”
While in Edit mode you may tumble and navi-
gate as with any other mesh in Edit mode by clicking
outside the surface of the sphere on the background
of the document window. If you try to click the sur-
face of the sphere, you will notice that drawing on
the ZSphere will draw another sphere on its surface,
connecting it via a chain of concentric rings called
joints (Figure 6.4). You will also notice that ZSpheres
are two-toned with red and dark red. This is to help
you spot twisting in the chain. Twisting will only
be calculated into the mesh when you are using the
“Classic” skinning method discussed later in this
chapter. A chain twisted beyond 180 degrees can
result in bad topology. We’ll cover that topic later in
this chapter, in the section “Moving, Scaling, and
Rotating ZSpheres and Chains.”Figure 6.2 You access ZSpheres via the Tool menu under Startup 3D Meshes.While drawing ZSphere chains, keep your Draw Size set to 1. This prevents you from acci-
dentally selecting another ZSphere because it falls under your draw radius. It is also help-
ful to keep X Symmetry on, even when you’re working on the center pillar of the body,
because it assists in centering the ZSpheres (as you’ll see shortly).Figure 6.1 A ZSphere body and the resulting polygon mesh.