ST_MaterialN-PolarDB(PolarDB)-阿里云帮助中心

Retrieves the Nth material from an sfmesh object.

Syntax

material  ST_MaterialN(sfmesh sfmeshObject, int4 index);

Parameters

Parameter	Description
sfmeshObject	The sfmesh object.
index	The index of the material. The index starts from 0.

Description

This function returns the Nth material in an sfmesh object.

Examples

select ST_MaterialN('{   "meshgeoms" : ["MESHGEOM(PATCH(TRIANGLESTRIP(0 0,0 10,10 10,10 0)))"],  "materials":[{"type":"db", "attributes": {"schema":"public","table":"t_material","column":"the_material","key":"num=1"}} ], "primitives" : [  {"meshgeom": 0, "material" : 0}],  "nodes" : [    {"primitive" : 0} ] }'::sfmesh, 0);

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