Simple Features
Simple Features are an OpenGIS standard which specifies digital storage of geographical data (point, line, polygon, multi-point, multi-line, etc) with both spatial and non-spatial attributes. Simple Features are based on 2D geometry with linear interpolation between vertices. In general, a 2D geometry is simple if it contains no self-intersection. The OpenGIS Simple Features specifications define various spatial operators, which can be used to generate new geometries from existing geometries.
Contents
Types
Point
Example: POINT (10 10)
LineString
Example: LINESTRING( 10 10, 20 20, 30 40)
Polygon
Example: POLYGON ((10 10, 10 20, 20 20, 20 15, 10 10))
Multipoint
Example: MULTIPOINT(10 10, 20 20)
Multipolygon
Example: MULTIPOLYGON(((10 10, 10 20, 20 20, 20 15, 10 10)),((60 60, 70 70, 80 60, 60 60)))
GeomCollection
Example: GEOMETRYCOLLECTION(POINT (10 10), POINT(30 30), LINESTRING(15 15, 20 20))
See also
External links
- OpenGIS Specifications (Standards)
- OpenGIS Simple Features Specification for CORBA (99-054)
- OpenGIS Simple Features Specification for OLE/COM (99-050)
- OpenGIS Simple Features Specification for SQL (99-054, 05-134, 06-104r3)
- OGR - OGR library which implements relevant OGC standards
- OpenGIS Simple Features Specifications For SQL
- MySQL 5.1 documentation on Spatial extensions
- PostGIS Simple Features implementation for PostgreSQL
- A short history lesson on simple features. [1]
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