This is how far I could get (with present wb, i.e. without werners magic commit) without resorting to approximated curves/lines.
This was done with Part workbench and Curves workbench.
It was a looot of clicking...
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- Arbitrary_four_sided_surface.png (46.96 KiB) Viewed 2095 times
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To have it working by the book, one must be able to force the sovereign surfaces to be tangent to the planes at each end (could not get it to work). And the surface creation type for them shall be "multi section surface" (in this case only two sections is used).
The empty space in the "rectangle" will be of the surface creation type "fill" (could not get that to work either), which I guess is a nurbs surface? Or can a bezier surface satisfy four arbitrary curves with tangency conditions along all four curves?
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For larger and more complex areas, just repeat the "Arbitrary four sided surface" but skip the one side and replace it with one of the previously created curves/sovereign surfaces.
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Everything is governed with two points:
- Vertex_1a_The_no_1_sovereign (under Curve_1 / Corner_1a)
- Vertex_2a_The_no_2_sovereign (under Curve_2 / Corner_2a)