AutoCAD® 2009 & AutoCAD LT® 2009 Bible

Chapter 23. Creating 3D Surfaces

In this chapter, you learn to create all types of surfaces, also called meshes. Surfaces have a great advantage over 3D wireframe models because you can hide back surfaces and create shaded images for easier visualization of your models. Surfaces also enable you to create unusual shapes, such as topological maps or free-form objects. Figure 23.1 shows a lamp drawn with surfaces.

Note

This chapter assumes that you are using the 3D Modeling Workspace.

Note

This entire chapter applies to AutoCAD only. For information on surfaces that AutoCAD LT can create, see Chapter 21.

You cannot obtain information about physical properties — such as mass, center of gravity, and so on — from surfaces. Such information can be obtained only from 3D solids, which are covered in the next chapter.

AutoCAD approximates curved surfaces by creating a mesh of planes at varying angles. You see the planes because AutoCAD displays them using a web of intersecting lines. AutoCAD defines the mesh by its vertices — where the lines intersect. Figure 23.2 shows a mesh with its vertices.

Figure 23.1. A lamp drawn with surfaces.

Figure 23.2. A surface mesh.

Converting Objects to Surfaces

Perhaps the simplest way to create a surface is to convert an existing object to a surface. The CONVTOSURFACE ...