ST_YupToZup - PolarDB - Alibaba Cloud Documentation Center

This topic describes the ST_YupToZup function. This function converts a model from Y-up coordinate system to Z-up coordinate system.

Syntax

sfmesh ST_YupToZup(sfmesh mesh);

Return value

The sfmesh object that is obtained after the Y and Z axes are flipped.

Parameters

Parameter	Description
sfmesh	The sfmesh object that you want to convert.

Description

This function flips the Y and Z axes of the sfmesh object. In some cases, you can call this function to convert a Y-up coordinate system to a Z-up coordinate system.

You can also call the ST_Affine function and perform the following matrix transformation operations to implement the conversion:

1.0, 0,   0,   0,
0,   0,   1.0, 0,
0,   -1.0,0,   0

Examples

SELECT ST_AsText(ST_YupToZup(ST_MeshFromText('{"version" : 1, "root" : 0, "meshgeoms" : ["MESHGEOM(PATCH(INDEXSURFACE Z (VERTEX(0 0 2,0 10 3,10 10 1,10 0 1),INDEX((0,1,2),(1,2,3)))))"], "primitives" : [{"meshgeom" : 0}], "nodes" : [{"primitive" : 0}]}')));

Result:

{"version" : 1, "root" : 0, "meshgeoms" : ["MESHGEOM(PATCH(INDEXSURFACE Z (VE
RTEX(0 0 2,0 10 3,10 10 1,10 0 1),INDEX((0,1,2),(1,2,3)))))"], "primitives" : 
[{"meshgeom" : 0}], "nodes" : [{"primitive" : 0,"matrix" : [1,0,0,-1,0,0,0,0,1
,0,0,0,0,0,0,1]}]}