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1082 Chapter 9: Surface Modeling
NURBSsurfaceobjectsincludesrolloutsthatlet
you create new NURBS sub-objects.
Example: Rollout for creating NURBS surface sub-objects
Tip: Another way to create curve and surface
sub-objects is to use the NURBS Creation Toolbox
(page 1–1083).
This is a summary of how to create sub-objects:
• An individual point sub-object is either an
independent point or a dependent point tied to
other NURBS geometry.
• Curve sub-objects are either independent point
cur ves or CV curves, or they are dependent
(page 3–928) curves whose geometry is based
on other curves or surfaces already present in
the model. For example, a blend curve is a
dependent curve sub-object that connects the
endpoints of two other curves.
• Surface sub-objects are either independent
point sur faces or CV surfaces, or they are
dependent (page 3–928) surfaces whose
geometry is based on other surfaces or curves
already present in the model. For example, a
blend surface is a dependent surface sub-object
thatconnectstheedgesoftwoothersurfaces.
• You can attach 3ds Max objects. If t he attached
object is not already a NURBS object, it is
converted to NURBS geometry. You can attach
a NURBS curve, another NURBS surface, or
aconvertible3dsMaxobject. Theattached
object becomes one or more curve or surface
sub-objects.
• You can import 3ds Max objects. The imported
object retains its p ar ameters. While it is p art
oftheNURBSobjectitrendersasaNURBS,
but you can still edit it parametrically at the
Imports sub-object level. At this sub-object
level,viewportsdisplayitsusualgeometry,
not its NURBS form. A NURBS curve can
import NURBS curves or spline curves. A
NURBS surface can import curves, surfaces, or
convertible 3ds Max objects.
Note: Yo u c a n d e t a c h a N U R B S s u b - o b j e c t t o
make it a new, top-level NUR BS object, and
you can extract an imported object to create an
independent, top-level object once again.
Qua d M enu for N UR B S Objects
While a NURBS object is selected and the Modify
panel is ac t ive, the quad menu (page 3–694)
displays two quadrants that are specifical ly for
NURBS editing .