Associative surfaces
automatically adjust to changes made to other, related objects.
When surface
associativity is on, surfaces
are created with a relationship to the surface or profiles that
created them.
Associativity allows
you to:
Reshape the generating profiles to automatically
reshape the surface.
Work with a group of surfaces as if they
were one object. Just as reshaping one face of a solid box adjusts
the entire primitive, reshaping one surface or edge in a group of
associated surfaces adjusts the entire group.
Use geometric constraints on the 2D profiles
of a surface.
Assign mathematical expressions to derive
properties of surfaces, such as height and radius. For example,
specify that the height of an extruded surface be equal to one half
the lengh of another object.
As you add more objects
and edit them, all these objects become related and create a chain
of dependency. Editing one object can ripple through and affect
all associated objects.
It is important to understand
the chain of associativity because moving or deleting one of the
links in the chain can break the relationship between all the objects.
NoteTo modify the shape
of a surface that is generated from a curve or spline, you must
select and modify the generating curve or spline, not the surface
itself. If you modify the surface itself, you will lose associativity.
When associativity is
on, the DELOBJ system variable
is ignored. If Surface Associativity and NURBS
Creation are both on,
surface are created as NURBS surfaces, not associative surfaces.
Save time by planning
your model ahead; you cannot go back and add associativity after
the model has been created. Also, be careful not to accidentally break
associativity by dragging objects away from the group.
Procedure
To create an associative
surface
Click Surface
tabCreate
panelSurface
Associativity.At the Command prompt,
enter surfaceassociativity.
Any new procedural surfaces
will be associative.
NoteNURBS creation overrides Surface
Associativity. If Surface Associativity and NURBS Creation are both
on, surface associativity will not work.
To see what objects a surface
is associated with
In a drawing, select an associative surface.
Open the properties palette, in Surface
Associativity, select Show from the Show Associativity
drop-down list.
Roll over the surface and nearby objects.
The associated objects,
such as generating curves or edge subobjects highlight as well as
the surface itself.
To turn associativity off
for a particular surface
In a drawing, select an associative surface.
Open the properties palette, in Surface
Associativity, select Non from the Maintain Associativity
drop-down list.
The surface maintains
its associativity to other objects. But any new objects that are
created will not be associated with this surface. It breaks the
chain of associativity.
To remove associativity
from a surface
In a drawing, select an associative surface.
Open the properties palette, in Surface
Associativity, select Remove from the Maintain Associativity
drop-down list.
The surface becomes a
generic surface. You can no longer change any or its properties
in the properties palette and it loses its relationship with other objects.
