8

1102 Chapter 9: Sur face Modeling
Parametric tessellation also solves this problem
for every kind of surface except
Ulofts(page
1–1197)
and UV lofts (page 1–1202) .
• If the View Dependent setting doesn’t seem
to be doing much, change the tessellation
(on the Surface Approximation rollout) from
Curvature to Spatial. You will then get a much
more drast ic change in face count.
•Togetamaptosmoothlycovertwoormore
surface without tiling, create another surface
whose shape covers and roughly conforms to
theoriginalsurfaces.Applythetexturetothe
larger surface. In the
Material Properties rollout
(page 1–1150)
for the original surfaces, set
Texture Surface to Projected, click Pick Source
Surface, and pick the larger surface. Adjust the
larger surface to fine-tune the map projection.
Hide the larger surface before you render.
•Tohavedifferentmapsonasurfacesub-object,
use different
mapping coordinates (page
3–1061)
,andmultiple map channels (page
3–1060)
.Onthe Material Properties rollout
(page 1–1150)
, change the Map Channel
value and then turn on Generate Mapping
Coordinates. (Each map channel requires its
own set of mapping coordinates.)
NURBS surface sub-objects let you set the map
channel directly, and don’t require you to apply
UVWMapmodifiersasotherobjectsdo.
•Ifamapdoesn’taligntoasurfacesub-objectthe
way you want it to, on the
Material Properties
rollout (page 1–1150)
choose User Defined as
the Texture Surface, and then use Edit Texture
Points or the E dit Texture Surface dialog to
movethepointsofthetexturesurface.
• To adjust how the map aligns to the edges of
asurfacesub-object,usetheTextureCorner
settings on the
Material Properties rollout (page
1–1150)
.
NURB S Sur face Primitives
NUR B S S urf aces
Create panel > Geometry > NURBS Surfaces
Create menu > NURBS > CV Surface/Point Su rface
NURBS (page 3–1074) surface objects are the
basis of NURBS models. The initial surface you
create using t he Create panel is a planar seg ment
w ith points or CVs. It is meant simply to be "raw
material" for creating a NURBS model. Once
youhavecreatedtheinitialsurface,youcan
modify it on the Modify panel by moving CVs or
NURBS points, attaching other objects, creating
sub-objects, and so on.
There are two kinds of NU RBS surfaces:
Point Surface (page 1–1103)
CV Surface (page 1–1105)
Yo u c a n a l s o create a NURBS surface f rom a
geometric primitive (page 1–1117)
.
NURBS surfaces can contain multiple sub-objects,
including NURBS points, NURBS curves, and
other NURBS surfaces. These sub-objects are
either dependent or independent.
Creating Cur ve Sub-Objects (page 1–1153)
Creating Surface Sub-Objects (page 1–1179)
Creating and Editing Point Sub-Objects ( page
1–1220)
Common Sub-Object Controls (page 1–1123)
Editing Point Sub-Objects (page 1–1124)
Editing Curve CV Sub-Objects (page 1–1128)
Editing Surface CV Sub-Objec ts (page 1–1132)
Editing Curve Sub-Objects (page 1–1136)