Name

ST_GetFaceEdges — 返回一组绑定的有序边 aface

Synopsis

getfaceedges_returntype ST_GetFaceEdges(varchar atopology, integer aface);

描述

返回一组绑定的有序边 aface 。每个输出由一个序列和edgeid组成。序列号以值1开头。

每个环形边的枚举从具有最小标识符的边开始。边的顺序遵循左侧规则(约束面位于每条有向边的左侧)。

可用性:2.0

This method implements the SQL/MM specification. SQL-MM 3 Topo-Geo和Topo-Net 3:例程详细信息:X.3.5

示例

-- Returns the edges bounding face 1
SELECT (topology.ST_GetFaceEdges('tt', 1)).*;
-- result --
 sequence | edge
----------+------
        1 |   -4
        2 |    5
        3 |    7
        4 |   -6
        5 |    1
        6 |    2
        7 |    3
(7 rows)
-- Returns the sequence, edge id
-- and geometry of the edges that bound face 1
-- If you just need geom and seq, can use ST_GetFaceGeometry
SELECT t.seq, t.edge, geom
FROM topology.ST_GetFaceEdges('tt',1) As t(seq,edge)
        INNER JOIN tt.edge AS e ON abs(t.edge) = e.edge_id;

另请参阅

GetRingEdges, AddFace, ST_GetFaceGeometry