R/create_provider.R

In riatelab/maptiles: Download and Display Map Tiles

#' @title Create a new tile provider
#' @description
#' Use this function to create new tiles provider.
#'
#' @param name name of the provider.
#' @param url url of the provider.
#' The url must contain \{x\}, \{y\} and \{z\} placeholders. It may also contain
#' \{s\} for sub-domains or \{apikey\} for API keys (see Examples).
#' @param sub sub-domains.
#' @param citation attribution text of the provider.
#'
#' @return a list is returned. This list can be used by \link{get_tiles}.
#' @export
#' @examples
#' statdia_toner <- create_provider(
#'   name = "stadia_stamen_toner",
#'   url = "https://tiles.stadiamaps.com/tiles/stamen_toner/{z}/{x}/{y}.png?api_key={apikey}",
#'   citation = "© Stadia Maps © Stamen Design © OpenMapTiles © OpenStreetMap contributors"
#' )
#' opentopomap <- create_provider(
#'   name = "otm",
#'   url = "https://{s}.tile.opentopomap.org/{z}/{x}/{y}.png",
#'   sub = c("a", "b", "c"),
#'   citation = "map data: © OpenStreetMap contributors, SRTM | map style: © OpenTopoMap (CC-BY-SA)"
#' )
#' IGN <- create_provider(
#'   name = "orthophoto_IGN",
#'   url = paste0(
#'     "https://data.geopf.fr/wmts?",
#'     "request=GetTile",
#'     "&service=WMTS",
#'     "&version=1.0.0",
#'     "&style=normal",
#'     "&tilematrixset=PM_6_18",
#'     "&format=image/jpeg",
#'     "&layer=ORTHOIMAGERY.ORTHOPHOTOS.BDORTHO",
#'     "&tilematrix={z}",
#'     "&tilerow={y}",
#'     "&tilecol={x}"
#'   ),
#'   citation = "IGN, BD ORTHO®"
#' )
#'
#' # Find TileMatrixSet and Style values
#' layer <- "ORTHOIMAGERY.ORTHOPHOTOS.BDORTHO"
#' path <- "https://data.geopf.fr/wmts?"
#' param_info <- "service=wmts&request=GetCapabilities&version=1.0.0"
#' url <- paste0("WMTS:", path, param_info, ",layer=", layer)
#' \dontrun{
#' tmp <- tempfile(fileext = ".xml")
#' sf::gdal_utils(
#'   util = "translate",
#'   source = url, destination = tmp,
#'   options = c("-of", "WMTS")
#' )
#' readLines(tmp)
#' }
create_provider <- function(name, url, sub = NA, citation) {
  return(list(src = name, q = url, sub = sub, cit = citation))
}