8

1242 Chapter 9: Sur face Modeling
Tessellation group
Viewports—When chosen, the rollout affects
how surfaces in the NURBS objec t are displayed
interactively in viewports, including shaded
viewports, and by the preview renderer.
TheViewportssurfacesettingsarealsousedwhen
you apply a mesh modifier such as Mesh Select to
the NURBS object. T his is important because the
modifier can affect the scene’s geometry.
R end er er—When chosen, the rollout affects how
surfacesintheNURBSobjectaredisplayedby
the renderer, and by the draft renderer for Quick
Render.
The next cluster of buttons lets you choose which
portions of the geometry are affected by the
surface approximation settings.
Base Sur face—Settings affect the entire surface.
This is the default.
Surf ace Edge—Turn on to set approximation values
fortessellatingsurfaceedgesthataredefinedby
tr im curves. With Lock turned off, the surface and
edge tessellation values are independent of each
other.
For object-level surfaces, this is unavailable unless
Lock (described b elow) is turned off.
Displaced Surface—Tur n on to s et a third ,
independent approximation setting for surfaces
that have a
displacement map (page 2–1352)
applied to them. Available only when Renderer is
chosen.
Using a preset approximation setting (in the
Presets group box) should give you faster results
for displaced surfaces.
Lock —(for object-level surfaces only) Locks the
BaseSurfacesettingstotheSurfaceEdgesettings.
In other words, surfaces and surface edges hav e a
relational tessellation setting un less Lock is tur ned
off. Default=on.
Tessellation Presets group
Lets you choose a preset low, medium, or high
quality surface approximation. While a preset
is chosen, the values it uses are displayed on the
Tessellation Method rollout.
Preset values are saved in the
3dsmax.ini file.
You can customize the preset values by using the
Surface Approximation utility (page 1–1247) .
Low—Selectsa(comparatively)low-qualitysurface
approximation. These are the default values:
View ports, Base Surface:
Method=Spatial and Curvature Edge=50.0
Distance=50.0 Angle=50.0 Merge=0.0 Advanced
Parameters > Minimum=0, Maximum=3
Renderer, Base Surface:
Method=Spatial and Curvature Edge=20.0
Distance=20.0 Angle=15.0 Merge=0.01 Advanced
Parameters > Minimum=0, Maximum=3
Renderer, Displaced Surface:
Method=Spatial and Curvature Edge=20.0
Distance=20.0 Angle=10.0 Merge=(Unavai lable)
Advanced Parameters > Minimum=0,
Maximum=2
Keyboard shortcut: ALT+1
Medium—(The default for both viewports and
rendering.) Selects a medium-quality surface
approximation. These are the default values:
View ports, Base Surface:
Method=Spatial and Curvature Edge=20.0
Distance=20.0 Angle=15.0 Merge=0.0 Advanced
Parameters > Minimum=0, Maximum=3
Renderer, Base Surface:
Method=Spatial and Curvature Edge=10.0
Distance=15.0 Angle=10.0 Merge=0.01 Advanced
Parameters > Minimum=0, Maximum=4