Download imagery tiles to a standard cache and load the data into raster objects. Facilities for 'AWS' terrain https://registry.opendata.aws/terrain-tiles/ terrain and 'Mapbox' https://www.mapbox.com/ servers are provided.
The ceramic package provides tools to download raster tiles from online servers.
Maintainer: Michael Sumner mdsumner@gmail.com (ORCID)
Other contributors:
Miles McBain (ORCID) [contributor]
Ben Raymond (regex wizardry) [contributor]
Any process that can trigger downloads will first check the ceramic_cache() in case the tile already exists.
It can also load raster data from online servers to obtain imagery, but we let GDAL manage that.
If you want to deal with the tiles downloaded directly, see ceramic_tiles().
The main functions are for downloading tiles and each accepts a spatial object for the first argument, alternatively a raster extent, or location:
get_tiles | Download tiles for a given service for an extent and resolution |
get_tiles_buffer | Download tiles based on location and buffer (width, height) in metres |
get_tiles_dim | Download tiles based on extent and output dimension in pixels |
get_tiles_zoom | Download tiles base on extent and zoom level |
Two helper functions will load imagery into a raster object:
cc_location | Download tiles and build a raster object of imagery |
cc_elevation | Download tiles and build a raster object of elevation data |
Administration functions for handling the file cache and required API key for on online service:
get_api_key | Return the stored key for online API, or NULL |
ceramic_cache | Report the location of the tile cache |
clear_ceramic_cache | Delete all files in the tile cache (use with caution!) |
Other functions that are either rarely used or considered subject to change:
ceramic_tiles | Find particular tiles from the cache |
mercator_tile_extent | Abstract raster-extent form of the spherical Mercator tile system, expressed in tile-index and zoom |
plot_tiles | Plot the tiles from ceramic_tiles |
tiles_to_polygon | Convert ceramic_tiles to simple features format |
cc_heard | Specific location hardcoded form of cc_location |
cc_kingston | Specific location hardcoded form of cc_location |
cc_macquarie | Specific location hardcoded form of cc_location |
Useful links: