9

Point Curve 1107
Points lie on the curve they define.
Dra wing T hree-Dimensi onal Cur ves
When you create a point curve, you can draw it in
threedimensions.Therearetwowaystodothis:
• Draw In All Viewports: T hi s toggle lets you use
any v iewport to draw the curve, enabling you
to draw three dimensionally.
•Using
Ct rl to drag points: While you draw a
cur ve, you can use the
Ct rl key to drag a point
offoftheconstructionplane.
With the
Ct rl –key metho d, further mouse
movement lifts the latest point off the construction
plane.Therearetwowaystousethis:
•Click-drag.Ifyouholddown
Ct rl and a ls o
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
Ct rl +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 metho d 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 viewport, in which case the software sets
the height of the point using the point’s Z axis in
the inactive viewport. This lets you set the height
of the poin t with accuracy.
Snaps (page 2–41) also work w hen you change the
height of a point. For example, if you turn on Point
snapping, you can set a point to have the same
height as another point by snapping to that other
point in an inactive viewport.
Procedure
To create a NURBS point curve:
1.
Go to the Create panel.
2. Turn on Shapes, and choose NURBS
Curves from the drop-down list.
3. Tu r n on Point Cu r ve.
4. In a viewport, click and drag to create the first
point, as well as the first curve segment. Release
the mouse button to add the second p oint. 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 clicki ng without
dragging, this also creates the curve ’s first point.
However, if you release the mouse button more
than five pixels away from where you initially
pressed it, this creates an additional poin t.
Whileyouarecreatingapointcurve,youcan
press
Backspace to remove the last point you
created, and then previous points in reverse
order .
If Draw In All Viewports is on, you can draw in
any viewpor t, creating a 3D curve.
To lift a point off the construction plane, use
the
Ctrl key as described earlier in this topic
under "Drawing T hree-Dimensional Curves."