9

Editing Surface Sub-Objects 1145
Mak e Independent—
Disabled if the surface is
independent. If the surface is dependent, clicking
this button makes it independent.
Wa rning: When you make a surface independent, you
lose the animation controllers for all objects that depend
on it in turn .
Remove Animation—
Removes animation
controllers from the selected surfaces.
Detach—Detaches the selected surface sub-object
from the NURBS model, making it a new top-level
NURBS surface object (page 1–1101).TheDetach
dialog (page 1–1228) is displayed, which lets you
name the new surface. The new object is no longer
part of the original NURBS model.
To create a new top-level NURBS surface that is a
copy of the selected surface, turn on Copy before
you click Detach.
Co py—When on, clicking Detach creates a copy of
the selected surface instead of detaching it from
the NURBS model. Default=off.
Renderable—When on, the surface renders. Turn
offtomakethesurfaceinvisibleinrenderings.
Default=on.
Display Normals—When on, the normal for each
selected sur face is displayed. There is one normal
per surface sub-object. The normal is displayed at
the surface’s UV origin, so displaying normals can
help you see how materials wil l be mapped. On
the other hand, the normal can be hard to see if
you are zoomed out. Default=off.
Flip Normals—Turn on to reverse the direction of
the surface normals. D efault=off.
Tip: The Flip Normals control is usef ul for viewing
a surface that is mostly concave or mostly convex.
With more complicated NURBS sur faces, you
often wan t to render both sides of the surface.
Turn on Force 2-Sided in the Render Scene dialog
(page 3–2) to see both sides of the sur face. To see
both sides of the surfaces in viewpor ts, turn on
Force 2-Sided in the Rendering Method p anel of
the Viewport Configuration dialog (page 3–853),or
assign a Double-Sided Mate rial (page 2–1591).
Break R ow—Breaks t he surface into two sur faces in
the direction of a row (the surface’s U axis).
Break Col.—Breaks the surface into two surfaces in
the direction of a column (the surface’s V axis).
Break Both—Breaks the surface into four surfaces
in both directions.
You cannot break a trimmed surface.
Ex tend—Extendsthesurfacebychangingits
length.
Wa rn in g : Extending a surface loses all animation
controllers for t he surface and its points or CVs.
Join—
Joins two surface sub-objects together. After
you ha v e joined the surfaces in a viewport, the
Join Surfaces dialog (page 1–1233) is displayed.
This dialog lets you cho ose the method for joining
the two surfaces. You can join only original edges
of surfaces; you cannot join edges created by
trimming.
Wa rn in g : When you join two surface sub-objects, you
lose the animation controllers for all point or CVs on
both surfaces.
CV Surface rollout
This additional rollout is displayed when a CV
surface is selected.