8

1064 Glossary
have default smoothing groups. The default
material ID assignment depends on the type of
geometry. Most curved objects such as spheres
have a single material ID. Boxe s have six IDs, one
for each side. Cylinders have three: ID number 1
and2forthetwocaps,andIDnumber3forthe
sides. Hedra have three: one for each of their P,
Q, and R axes.
When you apply a Multi/Sub-Object material,
the m aterials wi ll match the Multi/Sub-Object
mater ial ID numbers to the material ID numbers
on the faces of the object. Faces keep a record of
the ID number, and not of the material name. If
the m aterial is anything but Multi/Sub-Object, the
material is assigned to the object’s entire surface.
Assigning some defining material ID number to
each object before they become compound object
operandscanbeausefultechniqueforbeingable
toselecttheseparatepiecesafterthey’recombined.
You can use material IDs for continuous surfaces
that require separate paints or finishes. For
example, a car constructed from different types of
materials, such as a colored metal body, chrome
parts, glass windows, and so on.
Yo u c a n u s e t h e
Material modifier (page 1–706) to
assign material ID numbers. Also you can reassign
materialIDsusingtheEditableMesh>Surface
Properties rollout, or Edit Mesh modifier > Edit
Surface rollout.
Material/Map Hierarchy
Material/map hierarchy shown i n the Material/Map
Navigator
TheMaterialEditorcouldbecalledtheMaterial
and Map Editor, because you can use it to design
both materials and maps, and any combinat ion of
the two. In addition, you can create material or
map hierarchies.
A material hierarchy is a material that consists
of other materials (or maps). Similarly, a map
hierarchy is a map consisting of other maps.
Materials that consist of other materials are
called
compound materials (page 3–1016) .Maps
consisting of maps are compound maps.