Vector Tiles Reader QGIS Plugin: Unterschied zwischen den Versionen
Stefan (Diskussion | Beiträge) K (→Enhancements and Ideas) |
Stefan (Diskussion | Beiträge) K (→About) |
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Available data sources (MBTiles): | Available data sources (MBTiles): | ||
| − | * Download MBTiles (compatible to "Mapbox Streets | + | * Download MBTiles (compatible to "Mapbox Streets v7") from [http://osm2vectortiles.org/downloads OSM2VectorTiles] project (see also city extracts). |
* There's a possibility to download single tiles from online resources, like "Mapbox Streets v7" (tbd.) | * There's a possibility to download single tiles from online resources, like "Mapbox Streets v7" (tbd.) | ||
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Available styles: | Available styles: | ||
* As of now, there is no QGIS styling available for a vector tiles product. See data model documentation above to help yourself. | * As of now, there is no QGIS styling available for a vector tiles product. See data model documentation above to help yourself. | ||
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== Known Limitations == | == Known Limitations == | ||
Version vom 11. April 2016, 15:32 Uhr
QGIS-Plugin Vector Tiles Reader - This Python plugin reads Mapbox Vector Tiles (MVT) from a local MBTiles file and loads them into a vector layer that is rendered by QGIS and it's (default) styling.
- A project by Geometa Lab HSR
- Project Lead: Stefan Keller
- Authors/Developers: see Github
>> This is Work in Progress! Expected release as experimental QGIS plugin April/May 2016 <<
Important websites:
- Source Code on Github: https://github.com/geometalab/Vector-Tiles-Reader-QGIS-Plugin
- QGIS plugin directory: http://plugins.qgis.org/vector_tiles_reader (tba.)
Inhaltsverzeichnis
About
About Vector Tiles: Though this is a vector representation, Vector Tiles are rather specific data targeted to visualization and thus not fully comparable to generic geospatial vector data formats. Because of many optimization issues Vector Tiles are lossy in many respect: Coordinates are converted to integers and thus loose precision, features are filtered at certain zoom levels and geometries like roads are simplified. Moreover they are "overzoomed" which means that they often borrow data from upper zoom levels.
Available data sources (MBTiles):
- Download MBTiles (compatible to "Mapbox Streets v7") from OSM2VectorTiles project (see also city extracts).
- There's a possibility to download single tiles from online resources, like "Mapbox Streets v7" (tbd.)
Data model documentation:
- Data model of OSM2VectorTiles.
- Data model of "Mapbox Streets v7".
Available styles:
- As of now, there is no QGIS styling available for a vector tiles product. See data model documentation above to help yourself.
Known Limitations
Limitations in general:
- This plugin is only tested on reading MBTiles containing Vector Tiles according to Mapbox Vector Tile Specification 2.1.
- CRS is always EPSG:3857 Web-Mercator. Though Vector Tiles are in principle not bound to a coordinate reference system (CRS), currently it's only possible to handle Vector Tiles in Web-Mercator EPSG:3857.
- There's no styling attached to MBTiles nor to Vector Tiles.
Limitations of current plugin:
- Lines and polygons remain cut off at tile boundaries. They can't be selected and highlighted like the original, since they are not yet stitched together.
- More tba.
Enhancements and Ideas
The plugin could read Vector Tiles directly from the web. But then - to behave similar to raster tiles - the problem of missing corresponding styling becomes even more prominent.
Installation and Source Code
Install from inside QGIS as Python plugin (Note: For plugin versions up to 0.9 you have to enable "experimental plugins").
