GeoPlatform Tilegarden¶
MVT Tiles¶
MVT tiles are a vector tile format, meaning geospatial data is represented as points, lines, and polygons in their native mathematical representation.
Advantages include
Their display can be customized client-side
Clients can run geospatial or geometric operations
Disadvantages include
Complex layers can take a long time to render and hog a lot of memory on the client
Raster Tiles¶
Raster tiles are images. precomputed to a level of detail at a particular zoom level
Advantages include
Lightweight rendering
Rendering speed and weight is unaffected by layer complexity
Disadvantages are
Harder to customize the display on the client
More disk space is required for pre-computed tiles
GeoPlatform Tilegarden¶
Both MVT and raster tiles (as PNG files) are rendered using AWS lambda. Tiles are cached in AWS S3 and can be precached for some higher zoom levels.
Usage¶
See GeoPlatform’s TerriaMap for an example of how raster tiles are used.
A list of available cached services in GeoPlatform are available here: https://www.geoplatform.gov/search?filters=format:%7C:GeoPlatform%20Services Anything marked with “Vector Tile Service” or “Raster Tile Service” is availble for preview with TileGarden tiles
Raster tiles from cached services can be used in QGIS. For example “https://tileservice.geoplatform.gov/tile/7670d620_0a7d_4c2d_b5e7_884d8deddf43/{z}/{x}/{y}.png” can be added as an XYZ Tile layer.
Data Updates¶
When data are updated, new cached layers are created, which will change the identifier in the URL. There is currently no permalink available, so check back in GeoPlatform for any updated cache services.
