With version 3.1, an additional skinning option for Metasurfaces is introduced. This allows to have a low number of generating cross sections (curves in surface direction) while matching given boundary curves, also called rails. See the simple example file attached.
In former versions, one solution to approximately match such boundaries has been to increase the number of cross sections - which is expensive and increases the data of the resulting NURBS Surface. Here, this new skinning method is a good alternative to the existing auto-cubic point interpolation. Finally, when it comes to the new BRep type that also comes with version 3.1, it is even recommended to exactly match boundaries for further processing such as Boolean Operations and fillet modeling.
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