2011

A different set of constraint bar icons are displayed when a horizontal or
vertical constraint is not parallel or perpendicular with the current UCS.
Use Fix Constraints
A fix constraint associates a constraint point on an object, or the object itself
with a fixed location with respect to the World Coordinate System.
It is often advisable to specify a fix constraint at an important geometric
feature. This locks the location of that point or object, and prevents geometry
from relocating when you make changes to the design.
When you fix an object, the angle of a line, or the center of an arc or circle is
also fixed.
Apply Multiple Geometric Constraints
You can apply multiple geometric constraints to objects either manually or
automatically.
When you want to apply all essential geometric constraints to a design
automatically, you can use AUTOCONSTRAIN with the objects that you select
in your drawing. This helps constrain the geometric shape of the
design—depending on your design, there might be cases where you need to
apply additional geometric constraints.
AUTOCONSTRAIN also provides settings in which you can specify the
following options:
■ What geometric constraints to apply
■ What order to apply geometric constraints
■ What tolerances are used to determine whether objects are horizontal,
vertical, or touching
628 | Chapter 18 Add Constraints to Geometry