WKT format

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WKT format (Well-known text) is a textual markup  language for representing the vector geometry of objects on the map. WKT format is defined in the standard ISO/IEC 13249-3:2016 "Information technology – Database languages – SQL multimedia and application packages – Part 3: Spatial" (SQL/MM) и в ISO 19162:2015, "Geographic information – Well-known text representation of coordinate reference systems".

Below there are given the types of objects and the corresponding record with the metric in the WKT format. When processing the objects MULTIPOINT, MULTILINESTRING, MULTIPOLYGON onto the map the appropriate number of objects combined into a set of objects will be applied.

 

Type

Examples

point

POINT (30 10)

linear

LINESTRING (30 10, 10 30, 40 40)

polygon

POLYGON ((30 10, 40 40, 20 40, 10 20, 30 10))

POLYGON ((35 10, 45 45, 15 40, 10 20, 35 10),
(20 30, 35 35, 30 20, 20 30))

Point set of objects

MULTIPOINT ((10 40), (40 30), (20 20), (30 10))

MULTIPOINT (10 40, 40 30, 20 20, 30 10)

linear 
set of objects

MULTILINESTRING ((10 10, 20 20, 10 40),
(40 40, 30 30, 40 20, 30 10))

polygon 
set of objects

MULTIPOLYGON (((30 20, 45 40, 10 40, 30 20)),
((15 5, 40 10, 10 20, 5 10, 15 5)))

MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)),
((20 35, 10 30, 10 10, 30 5, 45 20, 20 35),
(30 20, 20 15, 20 25, 30 20)))