An Angle constraint will replace an existing Parallel or Perpendic constraint on a given pair of linear elements. This is because Parallel and Perpendic are simply special cases of the Angle constraint.

The angle between the elements in an Angle pair is given as the difference between the slopes of the two elements (see Slope). If the Angle constraint is parameterized, this angle can be accessed via expression by referencing the parameter name.

AUTO will only extract angle constraints for line elements that share an endpoint or fillet. If you are assigning angle constraints manually, the members of the Angle pair need not be connected, refer to the following figure.