The method

PlanarFigure::EvaluateFeatures()

re-calculates quantities from PlanarFigure objects. It assumes, however, that the generated poly-line of the planar figure is up-to-date. It does currently NOT re-generate the poly-line if it needs to be updated first. Since it is not guaranteed that the poly-line is up-to-date, the poly-line should be re-generated if required.