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260 Chapter 5: Creating Geometry
Initial tex t shape with extruded shape below
Lathed obje ct with initial shape on ri ght
Lof ti ng S ha pes
Yo u c r e a t e Lofts (page 1–347) by combining two
or more splines in special ways. Shapes form the
lofting p ath, loft cross-sections, and loft fit curves.
Shapes as Animation Paths
You can use shapes to define the position of an
animated object. You create a shape and use it to
define a path that some other object follows.
Some possible ways for a shape to control animated
position are:
•Youcanusea
Path constraint (page 2–380) to
use a shape to control object motion.
• You can con vert a shape into position keys using
the Motion panel > Trajectories > Conv ert
From function (see
Trajectories (page 2–296) ).
See also
Edit Modifiers and E ditable Objects (page 1–491)
Modif ying at the Sub-Object Level (page 1–492)
Modifier Stack Controls (page 3–802)
Shape Check Utility
Utilities panel > Utilities rollout > More button Utilities
dialog > Shape Ch eck
The Shape Check utility tests spline and
NURBS-based s hapes and curves for
self-intersection and graphically displays
any instances of intersecting segments.
Self-intersecting shapes used to produce lathed,
extruded, lofted, or other 3D objects can result in
rendering errors.
The utility is "sticky" in that once you’ve picked
a shape object for it to check, you can pan/zoom
view ports and it w ill continually display the
locations of intersecting curves in the shape you
pick.
If a shape is animated, moving the time slider wi ll
recheck the shape on each frame of the animation,
allowing for easy checking of these changing
shapes.