2012

Once applied, constraints permit only those changes to the geometry that do
not violate the constraints. This provides a method for exploring design options
or making design changes while maintaining the requirements and
specifications of the design.
NOTE
The order in which you select two objects when you apply a constraint is
important in some cases. Normally, the second object you select adjusts to
the first object. For example, when you apply a perpendicular constraint, the
second object you select will adjust to become perpendicular to the first.
You can apply geometric constraints to 2D geometric objects only. Objects
cannot be constrained between model space and paper space.
Specify Constraint Points
With some constraints, you specify constraint points on objects instead of
selecting the objects. This behavior is similar to that of object snaps, but the
locations are limited to endpoints, midpoints, center points, and insertion
points.
For example, a coincident constraint can restrict the location of the endpoint
of one line to the endpoint of another line.
The following glyph is displayed on the object as you roll over the object.
Add Constraints to Geometry | 297