9

1194 Chapter 9: Surface Modeling
Inter face
When you tur n on the Ruled button, and whi le a
ruled surface sub-object is selected, a rollout with
the r uled surface parameters is displayed at the
bottom of the Modify panel.
Ruled Surf rollout (creation tim e )
Flip Beginning and Flip End—Flip one of the curve
directions used to construct the ruled surface.
A ruled surface is c reated using the directions
oftheparentcurves. Ifthetwoparentshave
opposing directions, the ruled surface can be
shaped like a b ow tie. To correct the situation,
use Flip Beginning or Flip End to construct the
ruled surface using a direction opposite the
corresponding parent curve’s direction. These
cont rols eliminate the need to reverse the curve.
Start Point 1 and Star t Point 2—Adjust the position
ofthestartpointatthetwocurvesthatspecify
the ruled sur face. Adjusting the start points can
help eliminate unwanted twists or "buckles" in the
surface.
Thesespinnersaredisablediftheedgesorcurves
are not closed.
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 dow n adjustment. When you release
the mouse button, the surf ace reappears.
Flip Normals—Turn on to reverse the direction of
the ru led sur face’s norma ls.
Ruled Surf rollout (modificatio n time)
Flip Beginning and Flip End—Flip one of the curve
directions used to construct the ruled surface.
A ruled surface is c reated using the direct ions
of the parent curves. If the two parents have
opposing directions, the ruled surface can be
shaped like a b ow tie. To correct the situation,
use Flip Beginning or Flip End to construct the
ruled surface using a direction opposite the
corresponding parent curve’s direction. These
controls eliminate the need to reverse the curve.
Start Point 1 and Start Point 2—Adjust the position
of the start point at the two curves that specify
the ruled sur face. Adjusting the start points can
help eliminate unwanted twists or "buckles" in the
surface.
These spinners are disabled if the edges or curves
are not closed.
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.
ReplaceFirstCurveandReplaceSecondCurve—Let
you replace the parent curves. Click a button,
then click the curve to replace the original first or
second curve.