What is WKT?
WKT stands for Well-Known Text and is a text markup language for representing vector geometry objects on a map, spatial reference systems of spatial objects and transformations between spatial reference systems.
At this moment, Qinsy supports a variant of WKT version 1. The WKT file that is used in Qinsy contains also transformations that normally are not supported by WKT version 1.
However, the Qinsy WKT version is not the same as WKT version 2 and will not work for the transformations that are available in WKT version 2.
WKT can represent the following distinct geometric objects:
- Point, MultiPoint
- LineString, MultiLineString
- Polygon, MultiPolygon, Triangle
- PolyhedralSurface
- TIN (Triangulated irregular network)
- GeometryCollection
WKT Export / Import
When a Geodetic Configuration is created in the Qinsy Geodetic Configuration User Interface, it is possible to export this configuration to a WKT string and send it to another user.
The next user can simply import this WKT string through the Load function of the Geodetic User Interface and will have the same configuration as defined by the first user.
Example
The following WKT example shows the information of the ETRS89 to Dutch Datum transformation:
TRANSFORM["ETRS89 (EUREF89) to Dutch Datum (RD)", GEOGCS["ETRS89", DATUM["European Terrestrial Reference System 1989", SPHEROID["GRS 1980", 6378137, 298.257222101, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]], AUTHORITY["EPSG", "7019"]], AUTHORITY["EPSG", "6258"]], PRIMEM["Greenwich", 0, AUTHORITY["EPSG", "8901"]], UNIT["degree", 0.0174532925199433, AUTHORITY["EPSG", "9102"]], AUTHORITY["EPSG", "4258"]], GEOGCS["Amersfoort", DATUM["Amersfoort", SPHEROID["Bessel 1841", 6377397.155, 299.1528128, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]], AUTHORITY["EPSG", "7004"]], AUTHORITY["EPSG", "6289"]], PRIMEM["Greenwich", 0, AUTHORITY["EPSG", "8901"]], UNIT["degree", 0.0174532925199433, AUTHORITY["EPSG", "9102"]], AUTHORITY["EPSG", "4289"]], PARAM_MT["molodensky_badekas", PARAMETER["cx", 3904046.173, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["cy", 368161.312, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["cz", 5013449.051, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["dx", -593.0248, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["dy", -25.9984, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["dz", -478.7459, UNIT["meter", 1, AUTHORITY["EPSG", "9001"]]], PARAMETER["ex", -1.9342, UNIT["microradian", 9.9999999999999995e-007, AUTHORITY["EPSG", "9109"]]], PARAMETER["ey", 1.6677, UNIT["microradian", 9.9999999999999995e-007, AUTHORITY["EPSG", "9109"]]], PARAMETER["ez", -9.1019, UNIT["microradian", 9.9999999999999995e-007, AUTHORITY["EPSG", "9109"]]], PARAMETER["ppm", -4.0725, UNIT["part per million", 9.9999999999999995e-007, AUTHORITY["EPSG", "9202"]]], AUTHORITY["EPSG", "9636"]], AUTHORITY["EPSG", "4831"]] |