postgis_sfcgal

PostGIS SFCGAL functions

GPL-2.0

PGDG

postgis : PostGIS SFCGAL functions

Overview

ID	Extension	Package	Version	Category	License	Language
1503	postgis_sfcgal	postgis	`3.6.4`	GIS	GPL-2.0	C

Attribute	Has Binary	Has Library	Need Load	Has DDL	Relocatable	Trusted
--s-d-r	No	Yes	No	Yes	yes	no

Relationships
Requires	postgis
See Also	pointcloud pg_sphere q3c earthdistance pgrouting h3 mobilitydb
Siblings	postgis postgis_topology postgis_raster postgis_tiger_geocoder address_standardizer address_standardizer_data_us

Packages

Type	Repo	Version	PG Major Compatibility	Package Pattern	Dependencies
EXT	PGDG	`3.6.4`	18 17 16 15 14	`postgis`	`postgis`
RPM	PGDG	`3.6.3`	18 17 16 15 14	`postgis36_$v`	-
DEB	PGDG	`3.6.4`	18 17 16 15 14	`postgresql-$v-postgis-3`	-

Linux / PG	PG18	PG17	PG16	PG15	PG14
el8.x86_64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
el8.aarch64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
el9.x86_64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
el9.aarch64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
el10.x86_64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
el10.aarch64	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3	PGDG 3.6.3
d12.x86_64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
d12.aarch64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
d13.x86_64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
d13.aarch64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u22.x86_64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u22.aarch64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u24.x86_64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u24.aarch64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u26.x86_64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4
u26.aarch64	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4	PGDG 3.6.4

Source

Repository

git.osgeo.org/gitea/postgis/postgis

Install

Make sure PGDG repo available:

pig repo add pgdg -u    # add pgdg repo and update cache

Install this extension with pig:

pig install postgis;		# install via package name, for the active PG version
pig install postgis_sfcgal;		# install by extension name, for the current active PG version

pig install postgis_sfcgal -v 18;   # install for PG 18
pig install postgis_sfcgal -v 17;   # install for PG 17
pig install postgis_sfcgal -v 16;   # install for PG 16
pig install postgis_sfcgal -v 15;   # install for PG 15
pig install postgis_sfcgal -v 14;   # install for PG 14

Create this extension with:

CREATE EXTENSION postgis_sfcgal CASCADE; -- requires postgis

Usage

PostGIS SFCGAL: 3D geometry and advanced operations powered by SFCGAL

PostGIS SFCGAL provides advanced 2D and 3D spatial operations by wrapping the SFCGAL library. It adds support for 3D geometry operations, volume calculations, extrusion, tesselation, and other functions not available in the core PostGIS GEOS backend.

SFCGAL Function Reference

Setup

CREATE EXTENSION postgis_sfcgal;

3D Operations

3D Intersection and Difference

-- 3D intersection of two solids
SELECT ST_3DIntersection(
    ST_GeomFromText('POLYHEDRALSURFACE Z(((0 0 0,1 0 0,1 1 0,0 1 0,0 0 0)),((0 0 1,1 0 1,1 1 1,0 1 1,0 0 1)),((0 0 0,0 1 0,0 1 1,0 0 1,0 0 0)),((1 0 0,1 1 0,1 1 1,1 0 1,1 0 0)),((0 0 0,1 0 0,1 0 1,0 0 1,0 0 0)),((0 1 0,1 1 0,1 1 1,0 1 1,0 1 0)))'),
    ST_GeomFromText('POLYHEDRALSURFACE Z(((0.5 0.5 0.5,1.5 0.5 0.5,1.5 1.5 0.5,0.5 1.5 0.5,0.5 0.5 0.5)),((0.5 0.5 1.5,1.5 0.5 1.5,1.5 1.5 1.5,0.5 1.5 1.5,0.5 0.5 1.5)),((0.5 0.5 0.5,0.5 1.5 0.5,0.5 1.5 1.5,0.5 0.5 1.5,0.5 0.5 0.5)),((1.5 0.5 0.5,1.5 1.5 0.5,1.5 1.5 1.5,1.5 0.5 1.5,1.5 0.5 0.5)),((0.5 0.5 0.5,1.5 0.5 0.5,1.5 0.5 1.5,0.5 0.5 1.5,0.5 0.5 0.5)),((0.5 1.5 0.5,1.5 1.5 0.5,1.5 1.5 1.5,0.5 1.5 1.5,0.5 1.5 0.5)))')
);

-- 3D difference
SELECT ST_3DDifference(solid_a, solid_b) FROM solids;

-- 3D union
SELECT ST_3DUnion(solid_a, solid_b) FROM solids;

3D Measurements

-- 3D area of a surface
SELECT ST_3DArea(geom) FROM surfaces;

-- Volume of a solid
SELECT ST_Volume(geom) FROM solids;

Extrusion

-- Extrude a 2D polygon into a 3D solid
SELECT ST_Extrude(
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))'),
    0, 0, 10  -- dx, dy, dz
);

Tesselation and Triangulation

-- Tesselate a polygon into triangles
SELECT ST_Tesselate(
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))')
);

-- Constrained Delaunay triangulation
SELECT ST_ConstrainedDelaunayTriangles(
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))')
);

Other Functions

-- Straight skeleton of a polygon
SELECT ST_StraightSkeleton(
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))')
);

-- Approximate medial axis
SELECT ST_ApproximateMedialAxis(
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))')
);

-- Minkowski sum
SELECT ST_MinkowskiSum(
    ST_GeomFromText('LINESTRING(0 0, 4 0)'),
    ST_GeomFromText('POLYGON((0 0, 1 0, 1 1, 0 1, 0 0))')
);

-- Check planarity of a surface
SELECT ST_IsPlanar(geom) FROM surfaces;