This topic describes the ST_FromSuperMap function. This function converts a hypergraph-based sfmesh object to a World Geodetic System 1984 (WGS84)-based sfmesh object.
Syntax
sfmesh ST_FromSuperMap(sfmesh mesh);Parameters
Parameter | Description |
mesh | The sfmesh object that you want to convert. |
Description
This function coverts a hypergraph-based sfmesh object to a WGS84-based sfmesh object to facilitate computations. A hypergraph-based sfmesh object is described by using the east-north-up (ENU) system and local coordinate system. This makes computing and query inconvenient.
Examples
SELECT ST_AsText(ST_FromSupermap(the_mesh))
FROM t_sm_mesh
ORDER BY num;
-----------------
{"version" : 1, "srid" : 4326, "root" : 0, "meshes" : [{"root" : 0, "meshgeoms" : ["MESHGEOM(PATCH(POINT Z (116.375228273102 40.000091623698 13.8479756591842)))"], "primitives" : [{"meshgeom" : 0}], "nodes" : [{"primitive" : 0}]}], "primitives" : [{"mesh" : 0}], "nodes" : [{"children" : [1]}, {"primitive" : 0}]}