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ManualsBrandsAutodesk ManualsApplications3ds Max

1091

Creating NURBS Models 1079

cur ve remains a Shape object unless you add a

surfacesub-objecttoitwhenyouconvertittoa

NURBS surface (without changing its name).

Surf aces—There are two kinds of NURBS sur faces.

A point surface (page 1–1102) is controlled b y

points, which always lie on the surface. A CV

surface (page 1–1103) is controlled by control

vertices (CVs). Instead of lyi ng on the surface, CVs

form a control lattice (page 3–923) that surrounds

the surface. (This is similar to the lattice used by

the FFD [free-form deformation] modifiers.)

See Creating Surface Sub-Objects (page 1–1177)

and Editing Surface Sub-Objects (page 1–1141).

Curves—There are also two kinds of NURBS

curves. These correspond exactly to the two

kinds of surfaces. A point curve (page 1–1106) is

controlled by poin ts, which always lie on the curve.

A CV curve (page 1–1110) is controlled by CVs,

which don’t necessarily lie on the curve.

See Creating Surface Sub-Objects (page 1–1177)

and Editing Cur ve Sub-Objects (page 1–1135).

Points—Point surfaces and point curves have point

(page 1–1219) sub-objec ts. You can also create

separate point sub-objects that are not par t of a

surface or a curve.

See Creating and Editing Point Sub-Objects (page

1–1219).

CVs —CV surfaces and CV curves have CV

sub-objects. Unlike points, CVs are always part

of a surface or a curve.

See Editing Curve CV Sub-Objects (page 1–1127)

and Editing Surface CV Sub-Objects (page 1–1130).

Impor ts—Imports are 3ds Max objects, including

other NURBS objects. Within the NUR BS model,

they render as NURBS; but they retain their

original parameters and modifiers.

See A ttaching and Importing 3ds Max Objects (page

1–1120).

Sub-objects can be dependent (page 1–1087)

sub-objects whose geometry is related to the

geometry of other sub-objects.