2013

Table Of Contents
In addition to 3D solid and mesh objects, AutoCAD offer two type of surfaces:
procedural and NURBS.
Procedural Surfaces can be associative, maintaining relationships with
other objects so that they can be manipulated as a group.
NURBS Surfaces are not associative. Instead, they have control vertices
that allow you to sculpt shapes in a more natural way.
Use procedural surfaces to take advantage of associative modeling, and use
NURBS surfaces to take advantage of sculpting with control vertices. The
illustration below shows a procedural surface on the left, and a NURBS surface
on the right.
Choose a Surface Creation Method
Create procedural and NURBS surfaces using the following methods:
Create surfaces from profiles (page 342). Create surfaces from profile
shapes composed of lines and curves with EXTRUDE, LOFT, PLANESURF,
REVOLVE, SURFNETWORK, and SWEEP.
Create surfaces from other surfaces (page 374). Blend, patch, extend,
fillet, and offset surfaces to create new surfaces (SURFBLEND, SURFPATCH,
SURFEXTEND, SURFFILLET and SURFOFFSET).
Convert objects into procedural surfaces (page 377). Convert existing
solids (including composite objects), surfaces, and meshes into procedural
surfaces (CONVTOSURFACE command).
Convert procedural surfaces into NURBS surfaces (page 378). Some
objects cannot be converted directly to NURBS (for example, mesh objects).
In that case, convert the object to a procedural surface and then convert
it to a NURBS surface. (CONVTONURBS command).
370 | Chapter 8 Work with 3D Models