CG Modeling 3: Advanced - An Introduction to Computer Graphics for Artists - page 275

15.2.6 Conclusion

Subdivision surfaces are a viable option for many types of subjects, particularly in
fi lm and video games. They are generally not suitable for industrial design. Character
models in particular benefi t from this type of geometry. The strength of subdivision
surface models is that they can be used to make clean but arbitrary branching or high
degree genus models.

15.3 Exercise: Vehicle

Using the same criteria from the vehicle project in Sect. 14.5 , build a vehicle in
subdivision surfaces.

15.4 Sculpting

Sculpting applications allow artists to use tools that resemble traditional sculpting
tools to make extremely detailed models. Topology plays a role in the way the under-
lying mesh is subdivided, but because of the extraordinarily high number of subdivi-
sions, artists can for the most part ignore topological considerations. This means that
models can have very weak topology despite their extraordinary level of detail, but
sculpting applications have tools to allow users to fi x topology problems.

15.4.1 Industry Use

The fi lm and video game industries use sculpting tools extensively as part of their
texturing pipeline. They make very high resolution meshes, some more than
30,000,000 triangles, and then bake the high res geometry onto a lower resolution
mesh as normal maps (Fig. 15.3 ). The resulting low resolution object is nearly indis-
tinguishable from the high resolution mesh that was used to make the normal maps.
This allows artists to make real time character models that contain fi ne details such
as wrinkles or pores in the skin of a character. The limiting factor with this detail is
the texture map size allowed for the object.

15.4.2 Method

Sculpting applications vary more than traditional polygon mesh editing packages
because some are based on pixols, a 3D pixel, and others on subdivision meshes.
Either way, artists can start with a low resolution mesh from another program or