Modeling the Teeth and Gums

You can model the teeth with just a few ovals. Once these are lofted, close up the ends that can be seen. The other ends that will be embedded in the gums can be left open since they will not be visible. One can actually get away with modeling only one tooth and then reshaping it into the five or six other types. Half of the upper and lower teeth are shaped, duplicated and mirrored for the other side of the mouth (Figure 7-25).



Figure 7-25 The upper teeth and gums and the entire set of teeth and gums.



The gums are actually very simple. A NURBS sphere is flattened and made concave for the mouth cavity. This sphere is then placed at the root of the teeth so that it encloses all of them. Once it is placed against the teeth, it may need to be adjusted somewhat.


Another Method for Modeling a NURBS Head

A different way of modeling a NURBS head is to start the curves at the top of the head. The first curve defines the profile. It begins at the crown of the skull and curves down around the forehead, nose, lips, chin, and neck. The curve could continue down to the torso's waist or even to the feet. If you try to model the head and torso or the entire body at the same time, then be prepared spend a lot of time tweaking points all over the place. Some people prefer to concentrate on one part at a time, therefore they will model the head, torso, legs, arms, feet, and hands separately.

Figure 7-26 illustrates the rest of the vertical curves. This method works well for shaping eyelids, but for the most part the curves are not facing in the general direction of the head muscles. One also finds extra isoparms around the corners of the mouth which can result in creasing. The jaw bone is more difficult to model since the curves are not naturally aligned with the direction of the mandibula.



Figure 7-26 The curves start at the top of the head.

Once all the curves for either the right or left side of the head are formed, then they can be duplicated, mirrored and lofted. Another approach is to loft half the head. The loft option would remain open instead of going all the way around and closing the half head. The lofted head is then duplicated and mirrored. The two halves of the head are then aligned or attached to each other. Figure 7-27 shows a head with the two halves aligned. Extra isoparms may show up where the two halves are joined. Connecting two halves will also work for the first NURBS modeling technique.



Figure 7-27 A lofted head with vertical curves.

The next part discusses modeling a head with polygons. As mentioned before, the main disadvantages to polygons are that they do not deform as well during animation and do not render as smoothly.


This tutorial is an excerpt from Mastering 3D Animation
Peter Ratner is the author of 3-D Human Modeling and Animation.
He is the founder of the Computer Animation program at James Madison University where he is currently teaching.