Add GEOSGeom_homogenize - #1493
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nyalldawson
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Jul 29, 2026
| * input is a single-element GeometryCollection, then the input will be | ||
| * destroyed and the single element returned. If the elements are not | ||
| * homogeneous, or if the input is not a collection, it will be returned | ||
| * unmodified. Nested collections are collapsed during processing. |
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Given that the current logic is all collection specific, should the function be named accordingly? ie "GEOSGeom_homogenizeCollection"?
There's an argument to be made that generic homogenization should also do things like turn a multilinestring containing a single linestring to a linestring, or turning a curve polygon which only consists of linestring rings into a non-curved polygon, or a compound curve with only straight segments to a linestring, etc...
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Maybe the function should be GEOSGeom_simplifyStructure, and it should handle the curve->line cases you're describing.
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Adds a
GEOSGeom_homogenizefunction to flatten a geometry (remove nesting) and convert it to its most specific representation. The existingGeometryFlattenerclass provides this, but it was not exposed to the C API. I don't feel like "homogenize" is a great description of what this does, but it has the advantage of matching the PostGISST_CollectionHomogenizewhose semantics it shares. Alternatives:GEOSGeom_refine,GEOSGeom_flattenPossibly useful as a postprocessing step for
GEOSSplit; see #1482