We discussed smoothing in Hour 4, and the same considerations apply with characters. In some ways, it’s more important to think about smoothing as you are working with characters, because as a character deforms in animation, the smoothing you apply will greatly affect how it looks in your final images.
Smoothing Reduces Detail
Remember that smoothing the geometry by tessellation does just that: It smooths! Wherever there are details that are not represented by enough polygons to really “define” it, you are going to lose that detail a bit when you smooth the mesh. Take a look at how the profile of the nose changes slightly when we press the 3 key and preview the smoothing, as shown in Figure 8.26.
FIGURE 8.26. The nose before and after smoothing. Notice how the profile changes when smoothing is applied.
When you are getting close to making your final adjustments to a model, previewing the smoothing is important. Keep a close eye on areas where the geometry is protruding or receding, because smoothing will reduce the contrast in these areas the most.
Deciding on Smoothing
The issues regarding what type of smoothing to use are the same with characters as they are with non-organic geometry.
Under most circumstances, if you are using Mental Ray to render (and not the Maya software renderer or a third-party choice), smooth your geometry with Mental Ray’s smooth mesh preview (by pressing 3 with geometry selected). This is when smoothing can happen as a last step before rendering.
In some rare cases, certain deformers, constraints, or miscellaneous nodes depend highly on the geometry and you will need to smooth your mode using the Mesh, Smooth command. Things such as toon lines depend on topology, and in order for them to follow the contour of the model, you will have to smooth the mesh using the Smooth command and not Mental Ray smooth mesh preview.