[postgis-users] PointCloud to Delaunay Triangles

[Jonathan Moules]

Hi List,
I have a pointcloud, and I want to turn it into a TIN (so I guess ST_DelaunayTriangles), and then measure the length of the sides of the triangles.

Does anyone have any suggestions on how to do this, ideally in a performant fashion?


I've tried a few things, but I'm currently struggling to just turn the points into the TIN. The following fails with the error "set-valued function called in context that cannot accept a set" - alas googling doesn't find anything that explains clearly what the error means. I'm guessing it doesn't want to use an aggregation function (st_union and st_accum also fail), but it's not clear why.

SELECT
            st_collect(pc_explode((pa))::geometry)
from
            TABLENAME where cloud_id = 994

Any thoughts welcome.

Thanks,
Jonathan

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