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FIX: use more robust signed-area check for ring orientation - #2665
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Self-intersecting rings may produce incorrect is_ccw results from shapely. We can implement the shoelace formula with numpy dot products to determine the orientation ourselves which is more robust.
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Self-intersecting rings may produce incorrect is_ccw results from shapely. We can implement the shoelace formula with numpy dot products to determine the net orientation ourselves which is more robust.
https://en.wikipedia.org/wiki/Shoelace_formula
@rcomer I thought this might help some of the other boundary attachment arcs (this is a separate issue unfortunately), so I had AI do a quick investigation for me and it came up with this as a solution which made sense to me. Since it didn't solve my other problems I figured I would break it out here into a separate PR. I didn't check against the original geometries, so it would probably be useful to look at those too and make sure this fixes them.
closes #2483