9

Surf ace Modifier 847
5.
In the stack display, choose the Surface modifier
again. Now the five-sided NGon is a patch
object, consisting of a quad patch and a tri
patch.
Note: Ifthesplineobjectdidnotturninto
a patch, increase the Surface modifier’s
Threshold parameter until the patches appear.
Example continued: Adjusting the sha pe of the
spline:
1.
In the stack display, expand the Edit Spline
modifier’s hierarchy, and choose the Vertex
sub-object level.
2. In the Top viewport, select the top vertex of the
five-sided NGon.
Two vector handles are displayed. T hese
handles can b e moved on a ny axis.
3. Tur n on S elec t and Move on t he toolbar,
then drag the handles around in the Top
viewport.
Theshapeofthesplinechanges.
4. Belowthestackdisplay,turnontheShow
End Result On/Off Toggle button.
The patch changes shape to fit the spline.
Interfa ce
Spline Options group
Threshold—D e termines the overall distance that is
used to weld the vertices of the spline object. All
ver tices/vec tors within the threshold of each other
are treated as one. Threshold uses units set i n the
Units Setup dialog (page 3–848).
Note: Spline control handles are also treated as
vertices, so setting high Threshold levels can
produce unexpected results.
Flip Normals—Flips the normal direction of t he
patch surface.
Remove I nterior Patches—Removes interior faces
of an object that you would not normally see.
Thesearethefacescreatedwithinthecapsor
otherinteriorpatchesofthesametypeofaclosed
polygon.
Use only s elected segs—Only seg ments selected in
theEditSplinemodifierwillbeusedbytheSurface
modifier to create patches.
Note: SegmentSub-Objectdoesnothavetobeleft
onintheEditSplinemodifier.