Returns bounding box of the whole curve or a part of it. The box is axis-aligned in the specified local coordinate system. It is guaranteed to enclose the curve, but not guaranteed to be tight/minimal. 

If the range is unbound (e.g. by default), the bounding box of the whole curve (range can be obtained by the getInterval method) is computed. Otherwise the bounding box is computed only for the set of points with the parameter in the specified range. If coordSystem is NULL (e.g. by default), then bounding box is aligned with global coordinate axes. Otherwise, the box will be axis-aligned in the local coordinate system specified by the coordSystem matrix.