WKT је формат текстуалног приказа геометрија, који се користи у базама података (PostGIS, SpatiaLite) и GIS апликацијама. Једноставан и лак за интеграцију.
Кључне могућности
О формату WKT
WKT (Well-Known Text) is the textual encoding of geometry from the OGC standard: POINT(37.6177 55.7558), LINESTRING(...), POLYGON((...)). It is understood by every spatial database and library — PostGIS, SpatiaLite, Shapely, JTS, GEOS — and it can be read by eye, which makes the format indispensable while debugging.
The export is taken when geometry is needed as text: to paste into an SQL query, to put into a test, to pass coordinates to someone else's system, to take a quick look at what came out of the selected area at all.
The output is a single text file in UTF-8. At the top are comments with the bounding box of the area and the coordinate system, then it goes layer by layer: a line like "-- layer: roads" with one geometry per line underneath it. Coordinates are in WGS84 (EPSG:4326) with six decimal places — that is about ten centimeters on the ground.
One important thing: WKT stores shapes only. There are no names, types or other OpenStreetMap tags in the file — if you need attributes, take GeoJSON, GeoPackage or a CSV with a WKT column.
Који програм отвара WKT датотеке
Следећи програми и апликације могу да отворе, уреде и раде са WKT (Well-Known Text) (.wkt) датотекама извезеним из OSM2CDR:
Format specifications
- Open standard
- 3D coordinates supported
- Lossless (no quality loss)
- No attributes
- Output: 1 file
- Well-Known Text (OGC Simple Features). One geometry per line, human-readable. Direct INSERT into PostGIS / Spatialite.
Ко користи WKT карте
Како извести WKT
Како отворити након извоза
- PostGIS — paste the lines as they are: INSERT ... VALUES (ST_GeomFromText('POLYGON((...))', 4326)); the SRID must be specified.
- Python — from shapely import wkt, then wkt.loads(line) line by line, skipping the lines that begin with two hyphens.
- QGIS — the QuickWKT plugin pastes geometry from the clipboard onto a temporary layer; for a full-fledged layer it is easier to download GeoJSON right away.
- Tables — WKT is understood by CSV import in QGIS: "Add Delimited Text Layer", with geometry from the WKT field.
- Checking — ST_IsValid in PostGIS or shapely.is_valid: self-intersections after simplification do happen, and it is better to learn about them before loading into a database.
Популарне карте у формату WKT
Преузмите извозе карата у формату WKT (Well-Known Text)
Преузмите професионалне WKT карте из OpenStreetMap. Тренутачно генерисање, било која област.
Често постављана питања
Упоредите са другим форматима
Сродни формати
Често се извозе заједно
Related Articles
WKB and WKT: Geometry Formats for Developers
WKB and WKT: binary and text geometry formats. PostGIS, Shapely, GEOS. When to use which, conversion, performance, and e
formatWKT (Well-Known Text) — OGC and ISO Text Standard for Geometries in SQL
WKT is the OGC Simple Features + ISO 19125 text representation of geometries: POINT/LINESTRING/POLYGON; backbone of Post