8
Patch 1085
Pa tch
Example of a p a tch model
A patch is a type of deformable object. A
patch object is useful for creating gently curved
surfaces, and provides very detailed control for
manipulating complex geometry.
When you apply an
Edit Patch modifier (page
1–617)
to an object or con vert it to an
editable
patch (page 1–950)
object, the software converts
the object’s geometry into a collection of separate
Bezier patches. Each patch is made up of three
or four vertices connected by edges, defining a
surface. Patches also have interior vertices that you
can control, or let the software control for you.
Yo u c o n t r o l a p a t c h s u r f a c e ’ s s h a p e b y
manipulating the vertices and edges. The surface
is the renderable geometry of the object.
Pa tch-B a s ed Ob j ects
Objects made from patches.
Physique (page
2–927)
can work with meshes, patches, NUR BS,
splines, and FFD space w arps.
Pa th
A p ath is the line (or other shape) a long which
shapes are lofted to create 3D
Loft objects (page
1–347)
.
The
Path constraint (page 2–380)
also lets you
assignalineorothershapeasa
motion path
.A
motion path is a form of
trajectory (page 3–1119)
.
Get Path (Lof ting)
A circle is lofted along a path to construct a tubular shape.
GetPathchoosesthepathspline
Yo u u s e G e t P a t h a s a l o f t c r e a t i o n m e t h o d w h e n
you want the path to move to the location of the
selected shape. For example, you use this metho d
if you have created a shape at the exact location
where you want the base of your loft object to be.
You use Get Path to create a loft at that location.
Get Path causes the path shape to move and rotate
to a l ign itself with the first shape on the path:
• The first vertex on the path is located at the first
shape’s pivot point.
• The tangent to the first vertex on the path is
aligned with the positive Z axis of the first
shape.
• T he local Z axis of the path is aligned with the
local Y axis of the first shape.
•Thelocalcoordinatesystemoftheresulting
loft object equals the loca l coordinate system of
the path af ter it has been alig ned with the first
shape.
Sometimes, alig ning the tangent of the path with
thepositiveZaxisofthefirstshapedoesnot