3

Probably a bit hard to explain but hopefully the image can explain better

There are 2 datasets, one is a point, the other is a line. Intended outcome is having polygons based on them

The lines form a shape around each point which I need to build a polygon out of, which I've highlighted as the shaded areas in yellow. But there can be multiple lines that can form each polygon, which I gave 2 examples in orange:

enter image description here

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Polygonize all lines then inner join your points to them, and select distinct polygons:

with polygonized as (
select l.id, st_makepolygon((st_dump(l.geom)).geom) as geom
from test.lines as l
)
select distinct on (polygonized.id) polygonized.* from polygonized
join test.points_in_lines as p
on st_intersects(polygonized.geom, p.geom)

enter image description here

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  • I needed to use ST_NumPoints(part_geom) >= 4 and ST_IsClosed(part_geom) otherwise it wouldn't work. But somehow it didnt work in many cases like in the below i.sstatic.net/QsN9WFIn.png
    – Luffydude
    Commented Jul 23 at 11:49
  • The polygon in your screenshot is self intersecting = invalid
    – Bera
    Commented Jul 23 at 15:01
  • Is there anyway to maybe make it at least a little bit tolerant of bad geometries? maybe like a buffer?
    – Luffydude
    Commented Jul 23 at 16:21

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