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Point Curve Sub-Object 1157
Point Curve Sub-Object
Selec t NURBS object. > Modify panel > C reate Curves
rollout > Point Curve button
Select NU RB S object. > Modify panel > NURBS toolbox >
Create Point Cur ve button
Point curve sub-objects are similar to object-level
point curves (page 1–1108) .Pointsareconstrained
tolieonthecurve.Themaindifferenceisthatyou
can’t give point curves a renderable thickness at
the sub-object level.
Dra wing T hr ee-Dimensional Cur v es
When you create a point curve, you can draw it in
threedimensions.Therearetwowaystodothis:
• Draw In All Viewp orts: This toggle lets you u s e
any viewp ort to draw the curve, enabling you
to draw three dimensionally.
• Using CTRL to drag points: While you draw
acurve,youcanusetheCTRLkeytodraga
point off of the construction plane.
With the CTRL key method , fur ther mouse
movement lifts the latest point off the construction
plane.TherearetwowaystouseCTRL:
• Click-drag.IfyouholddownCTRLandalso
hold down the mouse button, you can drag
to change the height of the point. The point’s
location is set when you release the mouse
button.
This method is probably more intuitive.
• Click-click. If you CTRL+click and then release
the mouse button, the height changes as you
drag the mouse. Clicking the mouse a second
time sets the point’s location.
This method is less prone to repetitive stress
injury.
Whileyouareoffsettingthepoint,areddotted
line is drawn between the original point on the
construction plane and the actual point offset
fromtheplane.Youcanmovethemouseintoan
inactive viewp ort, in which case the sof tware sets
the height of the point using the point’s Z axis in
the inac tive viewport. This lets you set the height
of the point with accuracy.
Snaps (page 2–38) also work w hen you change
the height of a point. For example, if you tur n on
Point snapping, you can set a point to have the
same heig ht as another p oint by snapping to that
other point in an inactive viewport.
Procedure
To create a point curve sub-object:
1.
Tur n on Point Cur ve .
2. In a viewport, click and drag to create the first
point, as well as the first curve segment. Release
the mouse button to a
dd the second point. Each
subsequent location you click adds a new point
to the curve. Right-click to end curve creation.
Note: If you begin the curve by clicking without
dragging, this al
so creates the curve’s first point.
However, if you release the mouse button more
than five pixels away from where you initially
pressed it, t his
creates an additional point.
Whileyouarecre
ating a point curve, you can
press BACKSPA CE to remove the last point you
created, and then previous points in reverse
order .
If Draw In All Vi
ewports is on, you can draw in
any viewp ort, creating a 3D curve.
To lift a point off the construction plane, use
theCTRLkeyasdescribedearlierinthistopic
under
Drawing
Three-Dimensional Curves
(page 1–1157)
.
As with splines, if you click over the curve’s
initial point, a
Close Cur ve dialog (page
1–1237)
is displa
yed. This dialog asks whether
youwantthecurvetobeclosed. ClickNoto