Graphics Programs Reference
In-Depth Information
To select an isoparm that isn't displayed on the surface, click a viewable isoparm and drag
the mouse to place the isoparm selection elsewhere on the surface. Release the button to
make the selection; a dashed isoparm line is now selected. This is a valid surface isoparm, but
it isn't one used to define the number of spans in the surface.
Insert Isoparms
You've already come upon a modeling assignment for which you needed extra surface
definition (that is, more spans) on a NURBS object. As you've seen, it's a matter of
selecting an isoparm and choosing Edit NURBS
➔
Insert Isoparms. Doing so creates an
isoparm and redefines the surface to add more spans. This function is used to make extra
detailed parts of a NURBS surface, to allow for smoother deformations—for example,
adding an isoparm or two to the elbow joint of a model to make the arm bend with a
cleaner crease (see Figure 5.20). You can either create a new isoparm between two exist-
ing ones or add isoparms to your own defined area.
Figure 5.20
Inserting isoparms
for a smoother
deformation
