| 172 | | ST_Boundary(geometry) (not really - always return a geometry a dimension lower - i.e. the boundary of a polygon is a polyline.)[[BR]] |
| 173 | | ST_box(geometry) (return a box object)[[BR]] |
| 174 | | ST_box2d(geometry) (return a box2d object)[[BR]] |
| 175 | | ST_box3d(geometry) (return a box3d object)[[BR]] |
| 176 | | ST_Envelope(geometry) |
| | 172 | ST_Boundary(geometry) (not really - always return a geometry a dimension lower - i.e. the boundary of a polygon is a polyline.)[[BR]][[BR]] |
| | 173 | ST_box(geometry) (return a PostgreSQL box object)[[BR]][[BR]] |
| | 174 | ST_box2d(geometry) (return a box2d object)[[BR]][[BR]] |
| | 175 | ST_box3d(geometry) (return a box3d object)[[BR]][[BR]] |
| | 176 | ST_Envelope(geometry) Returns the minimum bounding box for the supplied geometry, as a geometry. The polygon is defined by the corner points of the bounding box ((MINX, MINY), (MINX, MAXY), (MAXX, MAXY), (MAXX, MINY), (MINX, MINY)). (PostGIS will add a ZMIN/ZMAX coordinate as well). In PostGIS, the bounding box of a geometry is represented internally using float4s instead of float8s that are used to store geometries. The bounding box coordinates are floored, guarenteeing that the geometry is contained entirely within its bounds. This has the advantage that a geometry's bounding box is half the size as the minimum bounding rectangle, which means significantly faster indexes and general performance. But it also means that the bounding box is NOT the same as the minimum bounding rectangle that bounds the geometry.[[BR]][[BR]] |
