All Questions
5 questions
1
vote
0
answers
38
views
Why does ST_DelaunayTriangles return an empty GeometryCollection?
I'm currently struggling to calculate the area of a slightly non-planar surface in PostGIS. The area is a wall surface from a LOD2 data source.
Here's an example:
SELECT ST_AsText(ST_DelaunayTriangles(...
- 11
3
votes
0
answers
102
views
Apollonius Graphs (Delaunay Graphs of Disks) in sfcgal or PostGIS?
I was wondering if there is support for Delaunay Graphs of Disks (a.k.a. Apollonius Graphs) in PostGIS/sfcgal?
A CGAL function seems to exist for this. But I can't seem to find it in the PostGIS ...
- 11.2k
4
votes
2
answers
2k
views
St_delaunaytriangles polygon with holes
I'm using PostGIS to decompose a polygon with a few holes into triangles via st_delaunaytriangles. Unfortunately, it does not return the right result with holes, because the triangles being outputted ...
- 195
3
votes
2
answers
315
views
Query Z at intersecting point locations from a MultiPolygonZ?
I create a MultiPolygonZ geometry with ST_DelaunayTriangles().
select st_setsrid(
ST_CollectionExtract(
ST_DelaunayTriangles(
ST_GeomFromText('MULTIPOINT ...
- 2,299
1
vote
1
answer
858
views
Constrained Delaunay Triangulations in PostGIS?
It is possible to make Constrained Delaunay triangulations in PostGIS (PostgreSQL)? I have a Polygon and I need to make internal triangulation like this:
I tried to use ST_DelaunayTriangles but is ...
- 61