WKT (Well-Known Text)
Open BetaWKT ir teksta attēlojuma formāts ģeometrijām, ko izmanto datubāzēs (PostGIS, SpatiaLite) un GIS lietojumprogrammās. Vienkāršs un viegli integrējams.
Galvenās iespējas
Par WKT formātu
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.
Kura programma atver WKT failus
Tālāk norādītās programmas un lietotnes var atvērt, rediģēt un strādāt ar WKT (Well-Known Text) (.wkt) failiem, kas eksportēti no 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.
Kas izmanto WKT kartes
Kā eksportēt WKT
Kā atvērt pēc eksporta
- 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.
Populāras kartes formātā WKT
Eksportējiet kartes formātā WKT (Well-Known Text)
Lejupielādējiet profesionālas WKT kartes no OpenStreetMap. Tūlītēja ģenerēšana, jebkurš apgabals.
Biežāk uzdotie jautājumi
Salīdziniet ar citiem formātiem
Convert to WKT and back
What people who already downloaded say
Reviews are quoted in the language their authors wrote them in.
Наконец-то карты можно скачать в векторе. Автору спасибо!
всё очень круто, не ожидал что просто приду и скачаю кусочек карты! спасибо!!!
ОГРОМНОЕ СПАСИБО!!! ОЧЕНЬ ХОРОШАЯ ПРОГРАММА!!! Искал карту в векторе на стыке 3 стран - очень помогло!!
Ты - молодец! Сделал большое и нужное дело!
Иван, спасибо огромное! Не просто человек - Человечище!
иван, вы просто чудо. Спасибо за неимоверно крутой сервис
Относительно быстро и качественно собирает карты, самое приятно что бесплатно. удобно выбирать области
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