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Surf ace Display Rollout 1253
limit. You might want to increase this value to 7
(the greatest value allowed). Se e the description of
Advanced Parameters, below .
Merge—Controls the tessellation of surface
sub-objects whose edges are joined or very nearly
joined.Wheninputtoamodifier(suchasMesh
Select) that requires a mesh, and when NURBS
surfaces are tessellated for production rendering ,
by default the software adjusts the tessellation of
adjoining surfaces to match each other, in terms of
the number of faces along the edges. The Merge
parameter controls how this is done. If Merge is
zero, adjoining faces are unchanged. Increasing
thevalueofMergeincreasesthedistancethe
software uses to calculate how edges should match,
guaranteeing no gaps between the surfaces when
they are rendered. Default=0.01.
In most cases, you don’t need to adjust Merge. If
rendering shows gaps b etween nearly adjoining
faces, increase Merge to eliminate them.
Technically,theMergevalueisonetenthofone
percent of the diagonal of the object’s bounding
box. In other words, a Merge value of 1.0 (higher
than necessary for most purposes) is 0.1 percent
of the length of the diagonal. Because M erge is
based on the object’s dimensions, you can scale the
NURBS model without affecting the Merge setting.
Advanced Par ameter s—Click to display the
Advanced Surface A pproximation dialog (page
1–1246)
. The parameters in this dialog apply to
the Spatial, Curvature, and Spatial and Curvature
approximation methods.
Cle ar Su rf aces —When on, the settings you choose
in this utility override all sub-object specific
surface approximation settings in the selected
NURBS models. When off, the utility affects
top-level NURBS models but settings local to
individua l surface sub-objects remain unaffected.
Default=Off.
Set Sel ected—Applies the surface approximation
values active in the utility to all selected NURBS
objects.
Reset—Resets the values in the utilit y to the default
settings for a NURBS surface.
Surface Display Rollout
Utilities panel > Utilities rollout > More button > Utilities
dialog > Surface Approximation > Surface Display rollout
The controls in the Surface Display rollout are the
same as the display controls for NURBS surface
objects, with two additional buttons: Set Selected
and Reset.
Interf ace
Display group
Lattices—When on, displays control lattices, in
yellow lines. (You can change the lattice color
by using the
Colors panel (page 3–843) of the
Customize User Interface dialog. The Curve CV
and Surface CV sub-object levels also have a lo cal
Display Lattice toggle, which overrides this global
setting at the sub-object le vel. The Cur ve CV and
Surface CV settin gs are independent. In ot her
words,atthesub-objectlevel,youcanturnonthe