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1212 Chapter 9: Sur face Modeling
2-Rail Sweep Surface rollout (creation time)
Rail Curves—Showsthenamesofthetwocurves
you chose to be the rails.
Section Cur ves—Thislistshowsthenamesofthe
cross-section curves, in the order you click them.
You can selec t a curve by clicking its name in the
list. Viewports display the selec ted curve in blue.
Arrow Buttons—Usethesetochangetheorderof
sect ion curves in the list. Select a curve in the list,
andthenusethearrowstomovetheselectionup
or down.
Curve Properties group
These cont rols affect individual cur ves you select
in the S ec tion Curves list, as opposed to properties
of the sweep surface in general. They are enabled
onlywhenyouhaveselectedacurveintheSection
Curves list.
Reverse—When set, reverses the direction of the
selected curve.
Start Point—Adjusts the position of the curve’s
start point. This can help eliminate unwanted
tw ists or "buckles" in the surface.
This control is disabled if the curve is not a closed
curve.
While you’re adjusting start points, a dotted
blue line is displayed between them, to show the
alignment. The surface is not displayed, so it
doesn’t slow down adjustment. When you release
the mouse button, the surface reappears.
Insert—(Disabled.)
Remove—Removes a curve from the list. Select the
curve in the list, and then click Remove.
Refine—(Disabled.)
Replace—(Disabled.)
Sweep Para llel—When off, the rail curves define
a ruled surface, and the cross sections describe
lofting f rom this base ruled surface. When on,
each cross sect ion is associated with its best
fittingplane. Thisplanemovesalongtherails
and par allel to them. If the r ai ls are curved, the
plane can rotate. If the spacing between the rails
changes, the section scales or stretches. In either
case, the surface is blended from section to section
along its entire length. Default=off.
Sweep Scale—Whenoff,thesizeoftheplaneis
scaled only in the direction across the rails. When
on, the plane is scaled uniformly in all directions.
Default=off.
Snap Cross-S ections—When on, cross-section
cur ves are translated and scaled so they intersect
both rails. The first cross section is t ranslated
tothestartoftherails,andthelasttotheendof