Using an IndirectAttributeVariable<System.Double>, can be less efficient and is not recommended. The reason is that the operator must extend the requested view area with a margin that exceeds all possible values of MaxDisplacement * ShortestMatchFactor / 2. When ShortestMatchFactor is indirect, the operator does not know how large it may become, and it will assume that it may be as much as 20.0. If this default is larger than was necessary, the operator will be slower; if the default is too small, matches that are long enough in reality may appear too short because the polygons have been clipped by a RectangleClipOperator, and omitting the RectangleClipOperator would also slow down the operator.

Using an IndirectDoubleAttributeVariable, can be less efficient and is not recommended. The reason is that the operator must extend the requested view area with a margin that exceeds all possible values of maxDisplacement * shortestMatchFactor / 2. When shortestMatchFactor is indirect, the operator does not know how large it may become, and it will assume that it may be as much as 20.0. If this default is larger than was necessary, the operator will be slower; if the default is too small, matches that are long enough in reality may appear too short because the polygons have been clipped by a RectangleClipOperator, and omitting the RectangleClipOperator would also slow down the operator.

Using an IndirectDoubleAttributeVariable, can be less efficient and is not recommended. The reason is that the operator must extend the requested view area with a margin that exceeds all possible values of maxDisplacement * shortestMatchFactor / 2. When shortestMatchFactor is indirect, the operator does not know how large it may become, and it will assume that it may be as much as 20.0. If this default is larger than was necessary, the operator will be slower; if the default is too small, matches that are long enough in reality may appear too short because the polygons have been clipped by a RectangleClipOperator, and omitting the RectangleClipOperator would also slow down the operator.

Using an IndirectDoubleAttributeVariable, can be less efficient and is not recommended. The reason is that the operator must extend the requested view area with a margin that exceeds all possible values of maxDisplacement * shortestMatchFactor / 2. When shortestMatchFactor is indirect, the operator does not know how large it may become, and it will assume that it may be as much as 20.0. If this default is larger than was necessary, the operator will be slower; if the default is too small, matches that are long enough in reality may appear too short because the polygons have been clipped by a RectangleClipOperator, and omitting the RectangleClipOperator would also slow down the operator.