How to validate intersecting geoshape in odk xlsform definition

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1. What is the issue? Please be detailed.
The issue that I am facing is that users are mapping there polygon, which happens to be intersecting with the whole polygon itself, resulting in giving validation errors in the backend.
Please see the red marked area, that is what i am talking about.

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2. What steps can we take to reproduce this issue?
Is there a function or anything to verify this and validae the polygon while he is filling the form itself. Can i add any if else condition to verify this in xlsform definition only?

3. What have you tried to fix the issue?

4. Upload any forms or screenshots you can share publicly below.

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I dont think there is a ready way to do this on the fly whilst acquiring the geoshape (and the algorithms for detecting self-intersecting polygons are non-trivial). But you may be able to cleanup the data in your backend prior to further processing, depending on what GIS package you are using; eg ArcGIS has: https://pro.arcgis.com/en/pro-app/latest/tool-reference/topographic-production/repair-self-intersections.htm

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Ok. Thanks. We decided to make the check at the backend itself.

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