3Ds Max Modeling Basics Chapter 12

Modeling Basics

Modeling is the process of pure creation. Whether it is sculpting,
building with blocks, construction work, carving, architecture,
or advanced injection molding, many different ways exist for creating
objects. Max includes many different model types and even more
ways to work with these model types.
This chapter gives you the scoop on modeling in Max and introduces
you to many utilities and helpers that, well, help as you begin to
model objects.
Exploring the Modeling Types
You can climb a mountain in many ways, and you can model one in
many ways. You can make a mountain model out of primitive objects
like blocks, cubes, and spheres, or you can create one as a polygon
mesh. As your experience grows, you discover that some objects are
easier to model using one method and some are easier using another.
Max offers several different modeling types to handle various modeling
situations.
Parametric objects versus editable objects
All geometric objects in Max can be divided into two general
categories—parametric objects and editable objects. Parametric
means that the geometry of the object is controlled by variables
called parameters. Modifying these parameters modifies the
geometry of the object. This powerful concept gives parametric
objects lots of flexibility. For example, the sphere object has a
parameter called Radius. Changing this parameter changes the
size of the sphere. Parametric objects in Max include all the
objects found in the Create menu.
Editable objects do not have this flexibility of parameters, but they
deal with subobjects and editing functions. The editable objects
include Editable Spline, Mesh, Poly, Patch, and NURBS. Editable
objects are listed in the Modifier Stack with the word Editable in
front of their base object (except for NURBS objects, which are
simply called NURBS Surfaces). For example, an editable mesh
object is listed as Editable Mesh in the Modifier Stack.

Actually, NURBS objects are a different beast altogether. When created using the Create
menu, they are parametric objects, but after you select the Modify panel, they are editable
objects with a host of subobject modes and editing functions.
Editable objects aren’t created; instead, they are converted or modified from another object.
When a primitive object is converted to a different object type like an Editable Mesh or a
NURBS object, it loses its parametric nature and can no longer be changed by altering its
base parameters. Editable objects do have their advantages, though. You can edit subobjects
such as vertices, edges, and faces of meshes—all things that you cannot edit for a parametric
object. Each editable object type has a host of functions that are specific to its type. These
functions are discussed in the coming chapters.
Several modifiers enable you to edit subobjects while maintaining the parametric nature of
an object. These include Edit Patch, Edit Mesh, and Edit Spline.
Max includes the following modeling types:
✦ Primitives: Basic parametric objects such as cubes, spheres, and pyramids. The primitives
are divided into two groups consisting of Standard and Extended Primitives. The
AEC Objects are also considered primitive objects. A complete list of primitives is
covered in Chapter 5, “Creating and Editing Primitive Objects.”
✦ Shapes and splines: Simple vector shapes such as circles, stars, arcs and text, and
splines such as the Helix. These objects are fully renderable. The Create menu includes
many parametric shapes and splines. These parametric objects can be converted to
Editable Spline objects for more editing. These are covered in Chapter 13, “Drawing and
Editing 2D Splines and Shapes.”
✦ Meshes: Complex models created from many polygon faces that are smoothed together
when the object is rendered. These objects are available only as Editable Mesh objects.
✦ Polys: Objects composed of polygon faces, similar to mesh objects, but with unique
features. These objects are also available only as Editable Poly objects. Mesh and Poly
objects are covered together in Chapter 14, “Working with Meshes and Polys.”
✦ Patches: Based on spline curves; patches can be modified using control points. The
Create menu includes two parametric Patch objects, but most objects can also be converted
to Editable Patch objects. Chapter 15, “Creating and Editing Patches,” covers
patches in detail.
✦ NURBS: Stands for Non-Uniform Rational B-Splines. NURBS are similar to patches in
that they also have control points. These control points define how a surface spreads
over curves. NURBS are covered in Chapter 16, “Working with NURBS.”
✦ Compound objects: A miscellaneous group of modeling types, including Booleans, loft
objects, and scatter objects. Other compound objects are good at modeling one specialized
type of object such as Terrain or BlobMesh objects. All the Compound objects
are covered in Chapter 17, “Building Compound Objects.”

✦ Particle systems: Systems of small objects that work together as a single group. They
are useful for creating effects such as rain, snow, and sparks. Particles are covered
along with the new Particle Flow interface in Chapter 18, “Creating Particles and
Particle Flow.”
With all these options, modeling in Max can be intimidating, but you learn how to use each of
these types the more you work with Max. For starters, begin with primitive or imported
objects and then branch out by converting to editable objects. A single Max scene can
include multiple object types.
Converting to editable objects
Of all the commands found in the Create menu and in the Create panel, you won’t find any
menus or subcategories for creating editable objects.
To create an editable object, you need to import it or convert it from another object type.
You can convert objects by right-clicking on the object in the viewport and selecting the
Convert To submenu from the pop-up Quadmenu, or by right-clicking on the base object in
the Modifier Stack and selecting the object type to convert to in the pop-up menu. Once converted,
all the editing features of the selected type are available in the Modify panel, but the
object is no longer parametric.
If a modifier has been applied to an object, the Convert To menu option in the Modifier Stack
pop-up menu is not available until you use the Collapse All command.
The pop-up menu includes options to convert to editable mesh, editable poly, editable patch,
and sometimes NURBS. If a shape or spline object is selected, then the object can also be converted
to an editable spline. Using any of the Convert To menu options collapses the Modifier
Stack.
Objects can be converted between the different types several times, but each conversion
may subdivide the object. Therefore, multiple conversions are not recommended.