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Postgis-挤出多边形
我想在Postgis中拉伸多边形以创建伪3D效果。为此，我编写了一个粗略的函数来实现它。这是非常多的测试代码，它为多边形上的每个点创建一个新的Y顶点，然后通过返回原始点将其关闭：- CREATE OR REPLACE FUNCTION public.extrude_polygon(wkb_geometry_param geometry, height integer, simplify boolean DEFAULT false) RETURNS geometry AS $BODY$ DECLARE f int; ret_geom geometry; wkb_geometry geometry; BEGIN --convert polygon to linestring IF ST_GeometryType(wkb_geometry_param) != 'ST_Polygon' THEN RETURN NULL; END IF; IF simplify THEN wkb_geometry = ST_Simplify(ST_Transform(ST_Exteriorring(wkb_geometry_param), 27700), 0.5); ELSE wkb_geometry = ST_Transform(ST_Exteriorring(wkb_geometry_param), …