locationtech / locationtech/jts

snapRoundingNoder on polygons result in MultiLineString

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Dominant language
Java
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Description

When using the snapRoundingNoder on the attatched dataset with a precision scale of 10, I get a MultiLineString where the number of decimal places are all reduced to 1, but the number of coordinate pairs go from 2818 in the original polygon data to 5419 in the resulting MultiLineString. This makes the data larger in bytes and more complex to work with. Is this the expected behavior?

Also, why is the result a MultiLineString? I don't see an obvious way to convert this back to polygons as there is no info on what were polygon exteriors and what were holes/interiors.

snap_problem_area_1144.txt

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Research direction

Reproduce the reported behavior with snapRoundingNoder, the attached snap_problem_area_1144.txt dataset, and a precision scale of 10. Compare the input polygon with the resulting MultiLineString and determine whether the coordinate expansion and loss of polygon ring information are expected; document the explanation or identify the needed fix.

Written by the indexing model from the issue text.

Assessment

Tech stack
java
Domain
computer-graphics
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
30/100

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