Schema
topology
Owner
postgres
Descriptions
args: geom, toponame, layer_id, tolerance - Converts a simple Geometry into a topo geometry
Options
Option | Value |
---|---|
Returns |
topology.topogeometry |
Language |
plpgsql |
Parameters |
ageom public.geometry atopology varchar alayer integer atolerance double precision = 0 |
Definition
CREATE OR REPLACE FUNCTION topology.totopogeom (
ageom public.geometry,
atopology varchar,
alayer integer,
atolerance double precision = 0
)
RETURNS topology.topogeometry AS
$span$
DECLARE
layer_info RECORD;
topology_info RECORD;
tg topology.TopoGeometry;
typ TEXT;
BEGIN
-- Get topology information
BEGIN
SELECT *
FROM topology.topology
INTO STRICT topology_info WHERE name = atopology;
EXCEPTION
WHEN NO_DATA_FOUND THEN
RAISE EXCEPTION 'No topology with name "%" in topology.topology',
atopology;
END;
-- Get layer information
BEGIN
SELECT *, CASE
WHEN feature_type = 1 THEN 'puntal'
WHEN feature_type = 2 THEN 'lineal'
WHEN feature_type = 3 THEN 'areal'
WHEN feature_type = 4 THEN 'mixed'
ELSE 'unexpected_'||feature_type
END as typename
FROM topology.layer l
INTO STRICT layer_info
WHERE l.layer_id = alayer
AND l.topology_id = topology_info.id;
EXCEPTION
WHEN NO_DATA_FOUND THEN
RAISE EXCEPTION 'No layer with id "%" in topology "%"',
alayer, atopology;
END;
-- Can't convert to a hierarchical topogeometry
IF layer_info.level > 0 THEN
RAISE EXCEPTION 'Layer "%" of topology "%" is hierarchical, cannot convert to it.',
alayer, atopology;
END IF;
--
-- Check type compatibility and create empty TopoGeometry
-- 1:puntal, 2:lineal, 3:areal, 4:collection
--
typ = geometrytype(ageom);
IF typ = 'GEOMETRYCOLLECTION' THEN
-- A collection can only go collection layer
IF layer_info.feature_type != 4 THEN
RAISE EXCEPTION
'Layer "%" of topology "%" is %, cannot hold a collection feature.',
layer_info.layer_id, topology_info.name, layer_info.typename;
END IF;
tg := topology.CreateTopoGeom(atopology, 4, alayer);
ELSIF typ = 'POINT' OR typ = 'MULTIPOINT' THEN -- puntal
-- A point can go in puntal or collection layer
IF layer_info.feature_type != 4 and layer_info.feature_type != 1 THEN
RAISE EXCEPTION
'Layer "%" of topology "%" is %, cannot hold a puntal feature.',
layer_info.layer_id, topology_info.name, layer_info.typename;
END IF;
tg := topology.CreateTopoGeom(atopology, 1, alayer);
ELSIF typ = 'LINESTRING' or typ = 'MULTILINESTRING' THEN -- lineal
-- A line can go in lineal or collection layer
IF layer_info.feature_type != 4 and layer_info.feature_type != 2 THEN
RAISE EXCEPTION
'Layer "%" of topology "%" is %, cannot hold a lineal feature.',
layer_info.layer_id, topology_info.name, layer_info.typename;
END IF;
tg := topology.CreateTopoGeom(atopology, 2, alayer);
ELSIF typ = 'POLYGON' OR typ = 'MULTIPOLYGON' THEN -- areal
-- An area can go in areal or collection layer
IF layer_info.feature_type != 4 and layer_info.feature_type != 3 THEN
RAISE EXCEPTION
'Layer "%" of topology "%" is %, cannot hold an areal feature.',
layer_info.layer_id, topology_info.name, layer_info.typename;
END IF;
tg := topology.CreateTopoGeom(atopology, 3, alayer);
ELSE
-- Should never happen
RAISE EXCEPTION
'Unsupported feature type %', typ;
END IF;
tg := topology.toTopoGeom(ageom, tg, atolerance);
RETURN tg;
END
$span$
LANGUAGE 'plpgsql'
VOLATILE
RETURNS NULL ON NULL INPUT
SECURITY INVOKER
COST 100;
COMMENT ON FUNCTION topology.totopogeom(ageom public.geometry, atopology varchar, alayer integer, atolerance double precision)
IS 'args: geom, toponame, layer_id, tolerance - Converts a simple Geometry into a topo geometry';
This file was generated with SQL Manager for PostgreSQL (www.pgsqlmanager.com) at 26/02/2014 11:51 |