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Vector Projected Curve 1171
Vector Pr oj ected Cur v e
Selec t NURBS o b je ct. > M odify panel > Create Curves
rollout > Dependent Curves group box > Vector Proj.
button
Select NURBS object. > Modify panel > NURBS toolbox >
Create Vector Projected Curve button
A Vector Projected curve lies on a surface. This
isalmostthesameasaNormalProjectedcurve,
except that the projection from t he original cu rve
to the sur face is in the direction of a vector t hat
you can control.
You can use vector projected curves for trimming
(page 1–1080).
Trimmingasurfacewithavectorprojectedcurve
If the projection intersects the surface in two or
more locations, the intersection closest to the seed
point is the one that creates the c urve.
Procedure
To crea te a vector proj ected curve:
1.
In a NURBS object that contains at least
onesurfaceandonecurvesub-object,clickto
turn on Vector P
rojected Curve in the NURBS
toolbox or Vector Proj. in the Create Curves
rollout.
2. Click the curve, then the surface where you
want the vector projection curve to lie.
Theinitialvectordirectionisintheview
direction. That is, the vector points away from
you as you look at the viewport. If the curve can
be projected onto the sur face in this direction,
the projection curve is created. The ori ginal,
parentcurvecango"offtheedgeofthesurface."
The projection curve is created only where the
projection and the sur face intersect.
Interfa ce
In viewports a gizmo (yellow by default) indicates
the projection axis. Transforming the gizmo
changes the projection onto the surface. Rotating
the g izmo is the most useful transform. You can
use rotation to adjust the distortion caused by
projection.
Vector Projected Curve rollout (creation time)
Trim Controls grou p
Tri m—When on, trims the surface against the
curve. When off, the surface isn’t trimmed.
If it’s impossible to trim with this curve, the surface
is displayed in the error color (orange by default).
For example, the curve is unusable for trimming if
it neither crosses the ed ge of the surface nor forms
aclosedloop.
Flip Trim—When on, t rims the surface in the
opposite direction.