92 chapter 3 ■ Designing a Character Bust
disturbing the faces of the head (Figure 3.24). This makes the process of sculpting the ears
independently of the head much easier, especially since you don’t have to constantly re-create
a complex mask. Any time you need to mask the head, ear or outer ring, simply hide the rest
of the mesh and mask the visible parts.Using Polygroups to Move the Mouth
The same problems with sculpting the ears also manifest when you’re trying to move the lips
independently of one another. When trying to mask or move the upper lip, you will often find
the lower lip is moved as well due to their proximity to each other. The brushes will simply
affect anything underneath their falloff rings that isn’t masked. The solution to this is to poly-
group the lower lip separately from the rest of the head. This makes it very simple to grab one
part of the mouth and quickly manipulate it while sculpting.
To polygroup the mouth, we will use steps similar to those we used with the ear, but
we first need to mask the lips separately from each other. This can be difficult since the lips
are so close; masking one lip invariably seems to create a mask on part of the other. We will
need to spread the lips open.- Store a morph target of your model by selecting Tool → Morph Target and clicking the
StoreMT button. This creates a copy of the mesh shape in memory that you can easily
return to. You are storing this morph target because you will now stretch the mouth
open to facilitate masking the lips. By returning to the stored shape, you can correct
any changes made to the mouth while keeping the mask.
Figure 3.22 Outer ring polygrouped
Figure 3.23 Masking with polygroups Figure 3.24 Using masking to help manipulate ear shapes