ST_3DShortestLine

ST_3DShortestLine
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描述

返回两个几何图形之间的三维最短直线。如果找到多行，则该函数只返回第一个最短的行。如果G1和G2仅在一点相交，该函数将返回一条起点和终点都在该交点的直线。如果G1和G2与多个点相交，该函数将返回一条起点和终点在同一点的直线，但它可以是任何交点。返回的行将始终以G1开始，以G2结束。此函数返回的线的3D长度将始终与 ST_3DDistance G1和G2的退货。

可用性：2.0.0

已更改：2.2.0-如果输入2个2D几何图形，则返回2D点(而不是假设缺少Z的行为为0)。在2D和3D的情况下，对于缺失的Z，不再假定Z为0。

This function supports 3d and will not drop the z-index.

This function supports Polyhedral surfaces.

示例

线串和点--三维和二维最短直线

SELECT ST_AsEWKT(ST_3DShortestLine(line,pt)) AS shl3d_line_pt,
                ST_AsEWKT(ST_ShortestLine(line,pt)) As shl2d_line_pt
        FROM (SELECT 'POINT(100 100 30)'::geometry As pt,
                        'LINESTRING (20 80 20, 98 190 1, 110 180 3, 50 75 1000)'::geometry As line
                ) As foo;


 shl3d_line_pt                                                                 |               shl2d_line_pt
----------------------------------------------------------------------------+------------------------------------------------------
 LINESTRING(54.6993798867619 128.935022917228 11.5475869506606,100 100 30)  | LINESTRING(73.0769230769231 115.384615384615,100 100)

线串和多点--三维和二维最短直线

SELECT ST_AsEWKT(ST_3DShortestLine(line,pt)) AS shl3d_line_pt,
                ST_AsEWKT(ST_ShortestLine(line,pt)) As shl2d_line_pt
        FROM (SELECT 'MULTIPOINT(100 100 30, 50 74 1000)'::geometry As pt,
                        'LINESTRING (20 80 20, 98 190 1, 110 180 3, 50 75 900)'::geometry As line
                ) As foo;


                       shl3d_line_pt                                       | shl2d_line_pt
---------------------------------------------------------------------------+------------------------
 LINESTRING(54.6993798867619 128.935022917228 11.5475869506606,100 100 30) | LINESTRING(50 75,50 74)

三维和二维最短直线的多重线串和面

SELECT ST_AsEWKT(ST_3DShortestLine(poly, mline)) As shl3d,
    ST_AsEWKT(ST_ShortestLine(poly, mline)) As shl2d
        FROM (SELECT  ST_GeomFromEWKT('POLYGON((175 150 5, 20 40 5, 35 45 5, 50 60 5, 100 100 5, 175 150 5))') As poly,
                ST_GeomFromEWKT('MULTILINESTRING((175 155 2, 20 40 20, 50 60 -2, 125 100 1, 175 155 1),
                (1 10 2, 5 20 1))') As mline ) As foo;
                   shl3d                                                                           |     shl2d
---------------------------------------------------------------------------------------------------+------------------------
 LINESTRING(39.993580415989 54.1889925532825 5,40.4078575708294 53.6052383805529 5.03423778139177) | LINESTRING(20 40,20 40)

另请参阅

ST_3DClosestPoint , ST_3DDistance , ST_LongestLine , ST_ShortestLine , ST_3DMaxDistance

Name

Synopsis

描述

示例

另请参阅