9

1200 Chapter 9: Surface Modeling
automatic alignment minimizes the amount of
twisting in the loft surface. Default=off.
Close Loft—If the loft was initially an open surface,
turning on this togg le closes it by adding a new
segmenttoconnectthefirstcurveandthelast
curve. Default=off.
Insert—Adds a curve to the U loft surface. Click
to tu rn on Insert, then click the curve. The curve
is inserted before the selected curve. To insert a
cur ve at the end, first highlig ht the "----End-----"
marker in the list.
Remove—Removes a curve from the U loft surface.
Selectthecurveinthelist,andthenclickRemove.
This button is available at creation time.
Refine—Refines the U loft su rface. Click to turn
onRefine,thenclickaU-axisisocurveonthe
surface. (As you drag the mouse over the surface,
theavailablecurvesarehighlighted.)Thecurve
you click is converted to a CV curve and inserted
into the loft and the U Curves list. As when you
refineapointcurve,refiningaUloftcanchange
the curvature of the surface slightly. Once you’ve
refined the surface by adding a U curve, you can
useEditCurvetochangethecurve.
Replace—Replaces a U curve with a different
cur ve. Select a U curve, click to turn on Replace,
then click the new curve in a viewp ort. Available
curves are h ighlighted as you drag the mouse.
This button is enabled only when you’ve selected a
single curve in the U Curves list.
Display Iso Curv es—When set, the U loft’s V-axis
isocurvesaredisplayedaswellastheU-axiscurves
used to construct the loft. The V-axis curves are
only for display. You can’t use them for surface
construction.
Edit Cur ve—Lets you edit the currently selected
curve without switching to another sub-object
level. ClicktoturnonEditCurve. Thepoints
or CVs of the curve are displayed, as well as the
control lattice if the curve is a CV curve. You can
now transform or otherwise change the points
or CVs as if you were at the Point or Curve CV
sub-object level. To finish editing the curve, click
to turn off Edit Curve.
WhenyouturnonEditCurves,allapplicable
rollouts for the selected curves are displayed,
including the Curve Common rollout, the CV
or Point rollout (depending on the curve type),
and the CV Cur ve or Point Curve rollout. These
rollouts appear beneath the U Loft rollout. They
let you edit the loft curves and their points or CVs
w ithout having to switch sub-object levels.
Tip: WhenyoueditcurvesinaUloft,turningoff
displayoftheUloftitselfcanmakethecurves
easier to see and improve performance. Use
Ctrl +D (whi le the Keyboard Shortcut Override
Toggle button (page 3–872) is on) to toggle display
of dependent sub-objects, including U Lofts.
UV Lof t Su r f ace
Select NURBS object. > Modify panel > Create Surfaces
rollout > D ependent Surfaces group box > UV Loft
Select NURBS object. > Modify panel > NURBS toolbox >
Create UV Loft Surface b utton
A UV loft surface is similar to a U loft surface, but
has a set of c urves i n the V dimension as well as in
the U dimension. This can give you finer control
over the lofted shape, and require fewer curves to
achieve the result you want.