■ Building a ZSphere Biped 211Figure 6.12 Rotate an entire sphere chain by clicking the connecting joint.
Figure 6.13 Rotating a sphere alone can create a twist in the mesh. To correct the rotations of
ZSpheres, select Rotate and Alt-drag to reorient the chain.
You can spot rotation errors in the sphere model by seeing if the ZSphere color codes
are consistent. Remember that ZSpheres are red and dark red, so you can visually spot the
orientation. In Figure 6.14, when I twist the spheres in the new skinning it creates issues like
the one pictured. Notice that the orientations don’t match, so the resulting mesh is twisted.
When corrected, the mesh is fine. This twisting will have less of an effect when you use the
default skinning method, but it is important to be aware of your ZSphere orientations. When
you use Classic Skinning under Tool → Adaptive Skin, the twist can create serious problems
in your resulting mesh. Twisting can be desirable when you want the underlying topology to
follow the direction of a muscle flow or the direction of the drapery you plan to sculpt.
Building a ZSphere Biped
You are now ready to apply your knowledge of the theory behind ZSpheres and some of
their basic controls to creating a biped character. Follow the steps in this section to build
a humanoid armature and generate a polygon mesh as a base for sculpting. For a video of
this process, see the accompanying DVD.