ST_TransformPipeline — Return a new geometry with coordinates transformed to a different spatial reference system using a defined coordinate transformation pipeline.
geometry ST_TransformPipeline(
geometry g1, text pipeline, integer to_srid)
;
Return a new geometry with coordinates transformed to a different spatial reference system using a defined coordinate transformation pipeline.
Transformation pipelines are defined using any of the following string formats:
urn:ogc:def:coordinateOperation:AUTHORITY::CODE
. Note that a simple
EPSG:CODE
string does not uniquely identify a coordinate operation:
the same EPSG code can be used for a CRS definition.
A PROJ pipeline string of the form: +proj=pipeline ...
. Automatic
axis normalisation will not be applied, and if necessary the caller will need to add an
additional pipeline step, or remove axisswap
steps.
Concatenated operations of the form: urn:ogc:def:coordinateOperation,coordinateOperation:EPSG::3895,coordinateOperation:EPSG::1618
.
Availability: 3.4.0
The SRID of the input geometry is ignored, and the SRID of the output geometry will be set to
zero unless a value is provided via the optional to_srid
parameter. When
using `ST_TransformPipeline()` the pipeline is executed in a forward direction. Using
ST_InverseTransformPipeline the pipeline is executed in the inverse direction.
Transforms using pipelines are a specialised version of ST_Transform. In most cases `ST_Transform` will choose the correct operations to convert between coordinate systems, and should be preferred.
Change WGS 84 long lat to UTM 31N using the EPSG:16031 conversion
-- Forward direction SELECT ST_AsText(ST_TransformPipeline('SRID=4326;POINT(2 49)'::geometry, 'urn:ogc:def:coordinateOperation:EPSG::16031')) AS utm_geom; utm_geom -------------------------------------------- POINT(426857.9877165967 5427937.523342293) (1 row) -- Inverse direction SELECT ST_AsText(ST_InverseTransformPipeline('POINT(426857.9877165967 5427937.523342293)'::geometry, 'urn:ogc:def:coordinateOperation:EPSG::16031')) AS wgs_geom; wgs_geom ---------------------------- POINT(2 48.99999999999999) (1 row)
GDA2020 example.
-- using ST_Transform with automatic selection of a conversion pipeline. SELECT ST_AsText(ST_Transform('SRID=4939;POINT(143.0 -37.0)'::geometry, 7844)) AS gda2020_auto; gda2020_auto ----------------------------------------------- POINT(143.00000635638918 -36.999986706128176) (1 row) -- using a defined conversion (EPSG:8447) SELECT ST_AsText(ST_TransformPipeline('SRID=4939;POINT(143.0 -37.0)'::geometry, 'urn:ogc:def:coordinateOperation:EPSG::8447')) AS gda2020_code; gda2020_code ---------------------------------------------- POINT(143.0000063280214 -36.999986718287545) (1 row) -- using a PROJ pipeline definition matching EPSG:8447, as returned from -- 'projinfo -s EPSG:4939 -t EPSG:7844'. -- NOTE: any 'axisswap' steps must be removed. SELECT ST_AsText(ST_TransformPipeline('SRID=4939;POINT(143.0 -37.0)'::geometry, '+proj=pipeline +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=au_icsm_GDA94_GDA2020_conformal_and_distortion.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg')) AS gda2020_pipeline; gda2020_pipeline ---------------------------------------------- POINT(143.0000063280214 -36.999986718287545) (1 row)