Definition
Simple Features refers to a standardized model for representing two-dimensional geometric objects in geographic information systems (GIS). It defines a set of geometry types and operations used to manipulate and query spatial data.
Overview
Developed and maintained by the Open Geospatial Consortium (OGC), the Simple Features specification provides a common framework for the storage, access, and manipulation of vector-based spatial data. It is widely implemented in GIS software, spatial databases (such as PostGIS), and geospatial programming libraries (e.g., GDAL, Shapely). The specification supports both binary (Well-Known Binary, WKB) and text-based (Well-Known Text, WKT) formats for representing geometric data.
Etymology/Origin
The term "Simple Features" originates from the OGC's effort to create an accessible and interoperable standard for basic geometric objects used in geospatial applications. The standard was first published in the late 1990s, with subsequent revisions enhancing functionality and consistency across platforms.
Characteristics
- Defines a set of fundamental geometric types: Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection.
- Specifies spatial operations such as intersection, union, distance, and containment.
- Supports coordinate reference systems (CRS) to define spatial context.
- Provides binary and text encodings (WKB and WKT) for data exchange.
- Designed for planar (flat-earth) geometry, not curved surfaces or topological relationships.
Related Topics
- Open Geospatial Consortium (OGC)
- Well-Known Text (WKT)
- Well-Known Binary (WKB)
- PostGIS
- GeoJSON
- Spatial Databases
- Computational Geometry
The Simple Features Access specification has become a foundational component in modern geospatial data handling, enabling consistent interpretation and processing of vector geometries across diverse software platforms.