3D point is spelled `POINT Z` not `POINTZ`
michaelkirk opened this issue · 11 comments
I recently merged #113, but I think it contains a critical error. I do not use 3-d points, so it slipped past me.
@ariesdevil - do you have interest in fixing this?
I thought the WKT spec allowed either POINTZ or POINT Z. I got a separate error from geozero when I passed in POINTZ
Oh - I truly don't know.
Trying to find an actual spec for WKT is making me laugh out loud. I guess we should probably just "do whatever JTS does".
I found this https://loc.gov/preservation/digital/formats/fdd/fdd000548.shtml, which links to some hundred page documents, but they seem to be about WKT CRS, and doesn't include the string "POINTZ" or "POINT Z"
Trying to find an actual spec for WKT is making me laugh out loud. I guess we should probably just "do whatever JTS does".
Yeah I was just searching for a spec and similarly couldn't find one. I suppose the ISO one is the "official" one. But I think this GEOS definition is enough.
I found this loc.gov/preservation/digital/formats/fdd/fdd000548.shtml, which links to some hundred page documents, but they seem to be about WKT CRS, and doesn't include the string "POINTZ" or "POINT Z"
Yeah it is confusing that there's both WKT for geometries and for CRS. Sadly the original simple features spec only defines WKB not WKT.
Shapely (GEOS) doesn't support POINTZ, it only supports POINT Z. So I think it's fine in this crate to only accept the latter
At first glance it looks like only point supports Z/M, and no other geometry types support it, so we should expand that support as well
Ok, I'm working on making this change.
Sorry I should've given you a heads up that I was looking into this. I put up #115
FWIW while I was reading through the GEOS code here, I saw that they do support both POINTZ and POINT Z. It seems strange they support both in GEOS when Shapely only supports the latter. But it looks like it produces POINT Z by default https://github.com/libgeos/geos/blob/main/include/geos/io/WKTWriter.h#L165-L179
Interesting. My understanding is that POINT Z is the "correct" way and POINTZ is a common enough misspelling that it might be worth supporting reading it (but not writing it) some day in the future.
This can be closed from #115