Modeling 1: Polygons - An Introduction to Computer Graphics for Artists - page 75

Loft

This tool takes two or more curves and creates a poly mesh from them. To do this,
it connects the endpoints of each successive curve, usually in the order selected, and
then, based on your settings for the tool, will either connect control points within the
curve or will evenly subdivide each curve into the same number of segments and
connect those.

Extrude

This tool will take one curve, copy it a given offset from its current location, and
then connect the two identical curves with polygons. You may have the option to
modify the curve globally during the offset, and to have multiple subdivisions along
the offset axis. You can also use another curve as an extrude path. For example, if
you extruded a circle along an arc-shaped path, the resulting shape would be a
half-torus.

Revolve

The revolve command is similar to the extrude command because it copies the
original curve a specifi ed offset, and then connects the curves with polygons. The
difference is that instead of a linear offset, it is radial and the end result is what you
would expect from turning a piece of wood on a lathe. You will have the option of
determining how many degrees of a curve you want in your fi nal object. This can
be a fraction of a full circle, a full circle, or more than a full circle. For the latter,
you should also have a linear offset option so that instead of getting overlapping
polygons as an end result, you get a helix, or screw thread shape.

Face

This simple command fi lls the curve with a single face, usually with many isolated
vertices.
There are more ways to constrain polygon construction by using curves than are
described here, but these are the most basic, and most commonly used, tools of this
type. They will be enough for almost all of your modeling work, and for some of
you, they will be enough for all of your future modeling needs.

6.3.3 Deleting Vertices

All of the following commands work on any component type, and all result in the
deletion of vertices (Fig. 6.6 ).