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282 Chapter 5: Creating Geometry
Helical spline varied only by bias settings
• A bias of –1.0 forces the turns toward the start
of the helix.
• A bias of 0.0 evenly distributes the turns
between the ends.
• A bias of 1.0 forces the turns toward the end of
the helix.
CW /CCW —The direction buttons set whether the
Helix turns clockwise (CW) or counterclockwise
(CCW).
Section Spline
Create panel > Shapes > Splines > Object Type rollout
>Section
Create menu > Shapes > Section
This is a special type of object that generates other
shapes based on a cross-sectional slice through
mesh objects. The Section object appears as a
bisected rectangle. You simply move and rotate
it to slice through one or more mesh objects, and
then click the Create Shape button to generate a
shape based on the 2D intersection.
Red line shows the section shape based on the structure.
Procedure
To creat e a nd us e a section s hape:
1.
Go to the Create p anel and choose
Shapes.
2. Click Sect ion.
3. Drag a rectangle in the viewport in which you
want to orient the plane. (For example, create it
intheTopviewporttoplacetheSectionobject
parallel w ith the XY home grid.)
The S ection object appears as a simple rectangle
with crossed l ines indicating its center. With
the default settings, the rectangle is for display
purposes only, because the effect of the Sec tion
objectextendsalongitsplanetothefullextents
of the scene.
4. Move and rotate the section so that its plane
intersects mesh objects in the scene.
Yellow lines are displayed where the sectional
plane intersects objects.
5. On the Create panel, click Create Shape, enter a
name in the resulting dialog, and click OK.
An editable spline (page 1–289) is created, based
on the displayed cross sections.