230 chapter 7 ■ Transpose, ZSphere Rigging, Retopology, and Mesh Extraction
In Transpose mode, there is another pow-
erful masking option called topology masking.
Topology masking creates a mask on the model
based on the underlying edge flow (Figure 7.7). In
a base mesh with evenly dispersed quad geometry
and edge loops that flow down the appendages, this
makes masking limbs quick and easy. The topology
generated by ZSphere models is especially effective
with this masking technique.
To mask by topology, hold down the Ctrl key
and drag the arm. Notice that the line produces a
mask that dynamically grows with the stroke. With
the entire arm masked, Ctrl-click off the model and
invert the mask so the arm is now unmasked. The edge
of the mask can be blurred or sharpened using the
Ctrl and Alt keys (Figure 7.8). Ctrl-click the masked
area to blur it and to create a more natural deforma-
tion; Ctrl+Alt-click to sharpen the masked area. This can also be accomplished with the
blurMask and sharpenMask buttons under Tool → Masking. You can adjust the amount of
blur or sharpening that is applied when you Ctrl-click by choosing Preferences → Transpose.
Topology masking is only accessible when Move, Rotate, or Scale mode is active.Figure 7.8 By Ctrl-clicking (left), you can blur a mask; using Ctrl+Alt-click (right), you can sharpen it.Posing a Figure
When posing a character, keep in mind some fundamental concepts. Where is the character’s
center of balance, where is the weight of the character placed in relation to the center, and
how is the character’s anatomy changing over the pose (meaning the extension and compres-
sion of the muscles)?
In Figure 7.9 I have labeled the skeleton, the center of balance, and the weight distribu-
tion on this character. The red lines represent the underlying skeleton. Notice that the left hip
is raised with the weight placed on the left leg. This shifting of weight across the center line
is called contrapposto. The blue line represents the center of gravity; this is always a straight
plumb line and is not necessarily in the center of the figure. Notice that the line of the hips is
at an angle opposite that of the shoulders.Figure 7.7 Topology masking