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264 Chapter 5: Creating Geometry
When Enable in Renderer is on, the shape is
rendered using a circle as a cross section. Mapping
coordinates are generated with U mapped once
around the perimeter, and V mapped once along
the length.
The software provides more control over
renderable shapes; viewports, including wireframe
viewports, can display the geometry of renderable
shapes. The rendering parameters for shapes
appear in their ow n rollout.
The Steps settings affect the number of cross
sections in the renderable shape.
Please observe the following:
• When you apply a modifier that converts a
shape into a mesh (such as Extrude (page
1–680) or Lathe (page 1–707)), the object
automatically becomes renderable, regardless
of the state of the Enable in Renderer check box.
You need to turn on the Enable in Renderer
check b ox only when you want to render an
unmodified spline shape in the scene.
• As with all objects, a shape’s layer must be on
for the shape to render. See Layer Properties
(page 3–656).
•TheObject Properties dialog (page 1–117) also
has a Renderable check b ox, which is turned on
by default. Both this check box and t he Genera l
rollout > Renderable check box must be turned
on in order to render a shape.
Shapes as Planar Objects
A st raightforward usage for shapes is 2D cutouts or
planar objects. Examples include ground planes,
text for signs, and cutout billboards. You create a
planar object by applying an Edit Mesh modifier
(page 1–634) to a closed shape, or by converting it
to an editable mesh object (page 1–996).
2D objects
Yo u c a n a l s o a p p l y a n E d i t M e s h m o d i f i e r t o a 3 D
shape (for example, a shape whose vertices have
been moved vertically away from the construction
plane by differe nt amounts) to create a curved
surface. The resulting 3D surface often requires
manual editing of faces and edges to smooth
surface ridges.
Extruded and Lathed Shapes
You can apply modifiers to a shape to create a 3D
object. TwoofthesemodifiersareExtrudeand
Lathe. Extrude (page 1–680) creates a 3D object
by adding height to a shape. Lathe (page 1–707)
creates a 3D object by rotating a shape about an
axis.