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Displace NURBS Modifier (World Space) 515
updated automatically because that can become
extremely time consuming.
Custom Settings—When turned off, Displace Mesh
uses default settings to subdivide the mesh for the
purposes of displacement mapping. When turned
on, the subdivision controls in this rollout are
enabled. Default=off.
Subdivision Displacement—Subdivides mesh faces
to accurately displace the map, using the method
and settings you specify in t he Subdivision Presets
and Subdivis ion Method group boxes. When
turned off, the modifier applies the map by moving
vertices in the mesh, the way the Displace modifier
(page 1–629) does. Default=on.
Split Mesh—Affectstheseamsofdisplacedmesh
objects; also affects texture mapping. When on,
the software splits the mesh into individual faces
before displacing them; this helps preserve texture
mapping.Whenoff,thesoftwareusesaninternal
method to assign texture mapping. Default=on.
Tip: This p arameter is required because of an
architectural limitation in the way displacement
mapping works. Turning Split Mesh on is usually
the better technique, but it can cause problems for
objects with clearly distinct faces, such as b oxes,
or even spheres. A box’s sides might separate as
they displace outward, leav ing gaps. And a sphere
might split along its longitudinal edge (found in
the rear for spheres created in the Top view) unless
you turn off Split Mesh. However, texture mapping
works unpredictably when Split Mesh is off, so
you might need to add a Displace Mesh modifier
and make a snapshot (page 1–453) of the mesh.
Yo u w o u l d t h e n a p p l y a UVW Map modifier (page
1–922) and then reassign mapping coordinates to
the displaced snapshot mesh.
Subdivision Presets group and Subdivisio n
Method group
Thecontrolsinthesetwogroupboxesspecifyhow
the mo difier applies the displacement map when
Custom Settings and Subdivision Displacement
are both turned on. They are identical to the
surface approximation controls (page 1–1239) for
NURBS surfaces.
Displace NURB S Modifier ( World
Space)
Select a NURBS object. > Modify panel > Modifier List >
World-Space M odifiers > * Displace NURBS
The Displace NURBS world-space modifier
(World Space) converts a NURBS (page 1–1078)
objectintoamesh. Ifadisplacementmapis
applied to the object, the mesh shows the effect of
the displacement map in viewports. There are two
main reasons for using Displace NURBS:
•Asavisualizationaidtoseetheeffectofa
displacement map in viewports
When you use Displace NURBS this way,
you usually delete the modifier once you’ve
obtained the effect you want.
• Toobtainaneditablemeshcreatedfroma
displacement map on a NURBS object
TouseDisplaceNURBSthisway,youapplyit
to the object that has a displacement map, then
use the Snapshot command (page 1–453) from
the Tools menu, and choose Mesh as the Clone
Method.
Snapshot creates a permanently displaced mesh.
As it does for other kinds of objects, Snapshot
also leaves t he original, displacement-mapped
object in the scene. After applying Snapshot,
you can delete the orig i nal object, or you c an
keep it in your scene to use for other purposes.
Interfa ce
The rollou t for Displace NURBS lets you choose
which surface approximation settings are used to
produce the mesh.