Graphics Programs Reference
In-Depth Information
proach seems more logical, especially if the project documentation requires numerous,
complex views of the same object. 3D modeling also is an absolute necessity when you
want to create rendered views for presentation purposes.
While the AutoCAD's 3D construction and visualization tools have improved dramatic-
ally over the years (trust me — you should have seen what they were like as recently as
AutoCAD 2006!), it's still a complex process that requires sophistication on the part of
the AutoCAD user. Although 3D modeling requires only one more dimension than 2D
drafting, developing 3D CAD models is considerably more complicated. Users must mas-
ter new techniques and contend with the 2D limitations of most display screens and in-
put devices.
In the previous chapter, I showed you how to move around models that others have
made, and explained the principles of 3D coordinate systems that you need to under-
stand to work in AutoCAD's 3D environment. This chapter introduces you to the con-
cepts, tools, and techniques of AutoCAD 3D modeling itself; here you can get your feet
wet creating your own 3D objects.
Full 3D support is one of the main differences between full AutoCAD and
AutoCAD LT. If you're using AutoCAD LT, you can look at and plot 3D models cre-
ated in AutoCAD, but you can't do much 3D object creation or editing yourself.
Also, viewing 3D models is less flexible in AutoCAD LT because it lacks nearly all
the 3D navigation tools in the full version of AutoCAD.
Is 3D for Me?
Traditional 2D drawings provide clues to help the viewer's mind construct a 3D model
from the 2D image on paper. Multiple views from different viewpoints in 3D space give
experienced designers, drafters, and builders the information they need to make 3D
sense of 2D drawings. Design and drafting have succeeded pretty well by using 2D rep-
resentations as the guide to creating 3D objects. But at some point, nothing can replace
a true 3D model, such as in helping someone understand how a building will look when
constructed or how two parts fit together.
What does using 3D in AutoCAD mean? Fundamentally, it means creating
models
instead
of
drawings
. Rather than generate cross sections of an object or individual views of it
from certain perspectives, you create a three-dimensional model of the object. This 3D
depiction of each object includes all the necessary information for AutoCAD to create a
drawing view from any point of view. With a properly constructed 3D model, AutoCAD
