Nothing
R/maps.R
In mapboxapi: R Interface to 'Mapbox' Web Services
Defines functions
get_vector_tiles
query_tiles
check_upload_status
upload_tiles
Documented in
check_upload_status
get_vector_tiles
query_tiles
upload_tiles
#' Upload dataset to your Mapbox account
#'
#' @param input An `sf` object, or the path to the dataset to upload as a
#' character string.
#' @param username Your Mapbox username
#' @param access_token Your Mapbox access token; must have secret scope
#' @param tileset_id The ID of the tileset in your Mapbox account
#' @param tileset_name The name of the tileset in your Mapbox account
#' @param keep_geojson Whether or not to keep the temporary GeoJSON used to
#' generate the tiles (if the input is an `sf` object)
#' @param multipart Whether or not to upload to the temporary AWS staging bucket
#' as a multipart object; defaults to `FALSE`.
#'
#' @examples \dontrun{
#'
#' # Example: create a tileset of median age for all United States Census tracts
#' # Requires setting a Mapbox secret access token as an environment variable
#'
#' library(mapboxapi)
#' library(tidycensus)
#' options(tigris_use_cache = TRUE)
#'
#' median_age <- get_acs(
#' geography = "tract",
#' variables = "B01002_001",
#' state = c(state.abb, "DC"),
#' geometry = TRUE
#' )
#'
#' upload_tiles(
#' input = median_age,
#' username = "kwalkertcu", # Your username goes here
#' tileset_id = "median_age",
#' tileset_name = "us_median_age_2014_to_2018"
#' )
#' }
#'
#' @export
upload_tiles <- function(input,
username,
access_token = NULL,
tileset_id = NULL,
tileset_name = NULL,
keep_geojson = FALSE,
multipart = FALSE) {
access_token <- get_mb_access_token(access_token, secret_required = TRUE)
# Allow input to be an `sf` object
if (any(grepl("^sf", class(input)))) {
input <- sf::st_transform(input, 4326)
if (is.null(tileset_name)) {
layer_name <- stringi::stri_rand_strings(1, 6)
} else {
layer_name <- tileset_name
}
if (keep_geojson) {
outfile <- paste0(layer_name, ".geojson")
path <- file.path(dir, outfile)
sf::st_write(input, path, quiet = TRUE)
} else {
tmp <- tempdir()
tempfile <- paste0(layer_name, ".geojson")
path <- file.path(tmp, tempfile)
sf::st_write(input, path, quiet = TRUE)
}
} else {
path <- input
}
# If tileset_id is NULL, use the basename of the input
if (is.null(tileset_id)) {
tileset_id <- gsub("\\.[^.]*$", "", basename(path))
}
# Get AWS credentials
base1 <- sprintf(
"https://api.mapbox.com/uploads/v1/%s/credentials",
username
)
req <- httr::POST(base1, query = list(access_token = access_token))
credentials <- httr::content(req, as = "text") %>%
jsonlite::fromJSON()
# Use these credentials to transfer to the staging bucket
aws.s3::put_object(
file = path,
object = credentials$key,
bucket = credentials$bucket,
region = "us-east-1",
key = credentials$accessKeyId,
secret = credentials$secretAccessKey,
session_token = credentials$sessionToken,
check_region = FALSE,
multipart = multipart
)
# Once done, generate the upload
url <- sprintf(
"http://%s.s3.amazonaws.com/%s",
credentials$bucket,
credentials$key
)
if (is.null(tileset_name)) {
upload <- sprintf(
'{"url": "%s", "tileset": "%s.%s"}',
url, username, tileset_id
)
} else {
upload <- sprintf(
'{"url": "%s", "tileset": "%s.%s", "name": "%s"}',
url, username, tileset_id, tileset_name
)
}
base2 <- sprintf(
"https://api.mapbox.com/uploads/v1/%s",
username
)
request <- httr::POST(base2,
httr::add_headers(
"Content-Type" = "application/json",
"Cache-Control" = "no-cache"
),
body = upload,
query = list(access_token = access_token)
)
response <- request %>%
httr::content(as = "text") %>%
jsonlite::fromJSON()
if (request$status_code != "201") {
stop(sprintf("Upload failed: your error message is %s", response),
call. = FALSE
)
}
message(sprintf("Your upload ID is %s", response$id))
}
#' Check the status of a Mapbox upload
#'
#' @param upload_id The upload ID
#' @param username Your account's username
#' @param access_token Your Mapbox access token
#'
#' @export
check_upload_status <- function(upload_id,
username,
access_token = NULL) {
access_token <-
get_mb_access_token(
access_token,
default = "MAPBOX_SECRET_TOKEN",
secret_required = TRUE
)
status <- httr::GET(
sprintf(
"https://api.mapbox.com/uploads/v1/%s/%s",
username, upload_id
),
query = list(access_token = access_token)
)
status %>%
httr::content(as = "text") %>%
jsonlite::fromJSON()
}
#' Get information about features in a tileset using the Tilequery API
#'
#' @param location The location for which you'd like to query tiles, expressed
#' as either a length-2 vector of longitude and latitude or an address you'd
#' like to geocode.
#' @param tileset_id The tileset ID to query.
#' @param radius The radius around the point (in meters) for which you'd like to
#' query features. For point-in-polygon queries (e.g. "what county is my point
#' located in?") the default of 0 should be used.
#' @param limit How many features to return (defaults to 5). Can be an integer
#' between 1 and 50.
#' @param dedupe Whether or not to return duplicate features as identified by
#' their IDs. The default, TRUE, will de-duplicate your dataset.
#' @param geometry The feature geometry type to query - can be `"point"`,
#' `"linestring"`, or `"polygon"`. If left blank, all geometry types
#' will be queried.
#' @param layers A vector of layer IDs you'd like to query (recommended); if
#' left blank will query all layers, with the limitation that at most 50
#' features can be returned.
#' @param access_token A Mapbox access token, which can be set with
#' [mb_access_token()].
#'
#' @return An R list containing the API response, which includes information
#' about the requested features. Parse the list to extract desired elements.
#' @seealso
#' <https://docs.mapbox.com/help/tutorials/find-elevations-with-tilequery-api/>
#'
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#'
#' elevation <- query_tiles(
#' location = "Breckenridge, Colorado",
#' tileset_id = "mapbox.mapbox-terrain-v2",
#' layer = "contour",
#' limit = 50
#' )
#'
#' max(elevation$features$properties$ele)
#' }
#'
#' @export
query_tiles <- function(location,
tileset_id,
radius = 0,
limit = 5,
dedupe = TRUE,
geometry = NULL,
layers = NULL,
access_token = NULL) {
access_token <- get_mb_access_token(access_token)
# If location is an address, geocode it
if (length(location) == 1) {
coords <- mb_geocode(location, access_token = access_token)
} else if (length(location) == 2) {
coords <- location
} else {
stop("The specified location must either be a
coordinate pair or a valid address",
call. = FALSE
)
}
# Format the requested layers if included
if (!is.null(layers)) {
layers <- paste0(layers, collapse = ",")
}
# Format the dedupe param
if (dedupe) {
dedupe <- "true"
} else {
dedupe <- "false"
}
# Construct the JSON for the request
base <- sprintf(
"https://api.mapbox.com/v4/%s/tilequery/%s,%s.json",
tileset_id, coords[1], coords[2]
)
# Build the request
query <- httr::GET(base, query = list(
radius = radius,
limit = limit,
dedupe = dedupe,
geometry = geometry,
layers = layers,
access_token = access_token
))
content <- httr::content(query, as = "text")
if (query$status_code != 200) {
pull <- jsonlite::fromJSON(content)
stop(pull$message, call. = FALSE)
}
result <- jsonlite::fromJSON(content)
return(result)
}
#' Retrieve vector tiles from a given Mapbox tileset
#'
#' @param tileset_id The name of the tileset ID; names can be retrieved from
#' your Mapbox account
#' @param location The location for which you'd like to retrieve tiles. If the
#' input is an `sf` object, the function will return data for all tiles that
#' intersect the object's bounding box. If the input is a coordinate pair or
#' an address, data will be returned for the specific tile that contains the
#' input.
#' @param zoom The zoom level of the request; larger zoom levels will return
#' more detail but will take longer to process.
#' @param access_token A Mapbox access token; which can be set with
#' [mb_access_token()].
#'
#' @return A list of `sf` objects representing the different layer types found
#' in the requested vector tiles.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#' library(ggplot2)
#'
#' vector_extract <- get_vector_tiles(
#' tileset_id = "mapbox.mapbox-streets-v8",
#' location = c(-73.99405, 40.72033),
#' zoom = 15
#' )
#'
#' ggplot(vector_extract$building$polygons) +
#' geom_sf() +
#' theme_void()
#' }
#'
#' @export
get_vector_tiles <- function(tileset_id,
location,
zoom,
access_token = NULL) {
access_token <- get_mb_access_token(access_token)
# If location is an `sf` object, get the bbox and the tiles that intersect it
if (any(grepl("^sf", class(location)))) {
bbox <- location %>%
sf::st_transform(4326) %>%
sf::st_bbox(.)
tile_grid <- slippymath::bbox_to_tile_grid(bbox = bbox, zoom = zoom)
tile_ids <- tile_grid$tiles
message(sprintf("Requesting data for %s map tiles. To speed up your query
choose a smaller extent or zoom level.", nrow(tile_ids)))
sf_list <- purrr::map2(tile_ids$x, tile_ids$y, ~ {
# Build the request to Mapbox
url <- sprintf(
"https://api.mapbox.com/v4/%s/%s/%s/%s.mvt",
tileset_id, zoom, .x, .y
)
request <- httr::GET(url, query = list(access_token = access_token))
# if (request$status_code != 200) {
# content <- httr::content(request, as = "text")
# stop(print(content$message), call. = FALSE)
# }
# Only try to read the data if there is data available
if (request$status_code == 200) {
sf_output <- protolite::read_mvt_sf(request$url)
return(sf_output)
}
})
# Now, combine the internal list elements by name
# First, find the tile with the most elements and get the names
max_ix <- purrr::map(sf_list, ~ length(.x)) %>% which.max()
# Next, grab the names of that list element
layer_names <- names(sf_list[[max_ix]])
names(layer_names) <- layer_names
# Now, iterate over the layer names, then the lists, keeping what you need
# and combining
master_list <- purrr::map(layer_names, function(name) {
# print(name) # Leave here for de-bugging
layer_list <- purrr::map(sf_list, ~ {
if (name %in% names(.x)) {
layer <- .x[[name]]
# If layer comes through as mixed geometry, we need to parse it into
# multiple list elements and return that
if (sf::st_geometry_type(layer, by_geometry = FALSE) == "GEOMETRY") {
sub_geoms <- list()
mixed_geoms <- sf::st_geometry_type(layer, by_geometry = TRUE)
if ("POINT" %in% mixed_geoms || "MULTIPOINT" %in% mixed_geoms) {
point_ix <- mixed_geoms %in% c("POINT", "MULTIPOINT")
sub_geoms$points <- layer[point_ix, ] %>%
suppressWarnings(sf::st_cast("MULTIPOINT"))
}
if ("LINESTRING" %in% mixed_geoms || "MULTILINESTRING" %in% mixed_geoms) {
line_ix <- mixed_geoms %in% c("LINESTRING", "MULTILINESTRING")
sub_geoms$lines <- layer[line_ix, ] %>%
sf::st_cast("MULTILINESTRING")
}
if ("POLYGON" %in% mixed_geoms || "MULTIPOLYGON" %in% mixed_geoms) {
polygon_ix <- mixed_geoms %in% c("POLYGON", "MULTIPOLYGON")
sub_geoms$polygons <- layer[polygon_ix, ] %>%
sf::st_cast("MULTIPOLYGON")
}
return(sub_geoms)
} else {
if ("POLYGON" %in% sf::st_geometry_type(layer)) {
# Remove malformed polygons
layer$layer_area <- sf::st_area(layer) %>% as.numeric()
layer <- dplyr::filter(layer, layer_area > 0)
layer <- sf::st_cast(layer, "MULTIPOLYGON")
layer <- dplyr::select(layer, -layer_area)
} else if ("LINESTRING" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTILINESTRING")
} else if ("POINT" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTIPOINT")
}
return(layer)
}
}
}) %>%
purrr::compact()
})
# Within the master list, we need to separate out by geometry type
# We'll have a mix of points, lines, and polygons for some
parsed_list <- purrr::map(layer_names, function(name) {
# ID the specific segment by layer name then smooth out any mixed geoms
segment <- master_list[[name]] %>%
rlang::flatten_if(predicate = function(x) inherits(x, "list"))
# identify how many geometries are in the list
geoms <- purrr::map_int(segment, ~ {
sf::st_geometry_type(.x, by_geometry = FALSE)
})
# If there is only one geometry, return the combined segment across the
# tiles
# Otherwise, we should give back points, lines, and polygons objects as
# appropriate
if (length(unique(geoms)) == 1) {
return(dplyr::bind_rows(segment))
} else if (length(unique(geoms)) > 1) {
output <- list()
if (2L %in% geoms || 1L %in% geoms || 5L %in% geoms) {
point_ix <- geoms %in% c(1L, 2L, 5L)
output$points <- segment[point_ix] %>%
dplyr::bind_rows() %>%
sf::st_cast("MULTIPOINT")
}
if (6L %in% geoms) {
line_ix <- geoms == 6L
output$lines <- segment[line_ix] %>% dplyr::bind_rows()
}
if (7L %in% geoms) {
polygon_ix <- geoms == 7L
output$polygons <- segment[polygon_ix] %>% dplyr::bind_rows()
}
return(output)
}
})
return(parsed_list)
}
# If location is a length-2 numeric vector of longitude/latitude, get the
# specific tile IDs
# If location is an address/text description, geocode it
if (is.vector(location)) {
if (inherits(location, "numeric")) {
if (length(location) != 2) {
stop("Location must be a length-2 vector of format c(lon, lat) if
supplying coordinates as input.")
}
} else if (inherits(location, "character")) {
location <- mb_geocode(location)
}
tile_id <-
slippymath::lonlat_to_tilenum(
location[1], location[2], zoom = zoom
)
# Build the request to Mapbox
url <- sprintf(
"https://api.mapbox.com/v4/%s/%s/%s/%s.mvt",
tileset_id, zoom, tile_id$x, tile_id$y
)
request <- httr::GET(url, query = list(access_token = access_token))
if (request$status_code != 200) {
content <- httr::content(request, as = "text")
stop(print(content$message), call. = FALSE)
}
sf_list <- protolite::read_mvt_sf(request$url)
# Iterate through the elements and parse into sub-elements when geometry is
# mixed
layer_names <- names(sf_list)
names(layer_names) <- layer_names
output_list <- purrr::map(layer_names, function(name) {
layer <- sf_list[[name]]
if (sf::st_geometry_type(layer, by_geometry = FALSE) == "GEOMETRY") {
sub_geoms <- list()
mixed_geoms <- sf::st_geometry_type(layer, by_geometry = TRUE)
if ("POINT" %in% mixed_geoms || "MULTIPOINT" %in% mixed_geoms) {
point_ix <- mixed_geoms %in% c("POINT", "MULTIPOINT")
sub_geoms$points <- layer[point_ix, ] %>%
suppressWarnings(sf::st_cast("MULTIPOINT"))
}
if ("LINESTRING" %in% mixed_geoms || "MULTILINESTRING" %in% mixed_geoms) {
line_ix <- mixed_geoms %in% c("LINESTRING", "MULTILINESTRING")
sub_geoms$lines <- layer[line_ix, ] %>%
sf::st_cast("MULTILINESTRING")
}
if ("POLYGON" %in% mixed_geoms || "MULTIPOLYGON" %in% mixed_geoms) {
polygon_ix <- mixed_geoms %in% c("POLYGON", "MULTIPOLYGON")
sub_geoms$polygons <- layer[polygon_ix, ] %>%
sf::st_cast("MULTIPOLYGON")
}
return(sub_geoms)
} else {
if ("POLYGON" %in% sf::st_geometry_type(layer)) {
# Remove malformed polygons
layer$layer_area <- sf::st_area(layer) %>% as.numeric()
layer <- dplyr::filter(layer, layer_area > 0)
layer <- sf::st_cast(layer, "MULTIPOLYGON")
layer <- dplyr::select(layer, -layer_area)
} else if ("LINESTRING" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTILINESTRING")
} else if ("POINT" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTIPOINT")
}
return(layer)
}
})
return(output_list)
}
}
#' Return a static Mapbox map from a specified style
#'
#' This function uses the [Mapbox Static Maps
#' API](https://www.mapbox.com/static-maps) to return a pointer to an
#' `"magick-image"` class image or a [httr::response] object from the static map
#' image URL.
#'
#' @inheritParams get_static_tiles
#' @param buffer_dist The distance to buffer around an input `sf` object for
#' determining static map, specified in units. If location is a POINT object
#' of 2 rows or less and `buffer_dist` is 0 or `NULL`, a 1 unit buffer is
#' applied to try to ensure the creation of a valid bounding box for the map
#' area.
#' @param units Units of `buffer_dist`; defaults to "m" (meters). If buffer_dist
#' is a units class object, the units argument is ignored.
#' @param style_id A style ID (required if style_url is `NULL`).
#' @param username A Mapbox username (required if `style_url = NULL`).
#' @param style_url A Mapbox style url; defaults to `NULL`.
#' @param overlay_sf The overlay `sf` object (optional). The function will
#' convert the `sf` object to GeoJSON then plot over the basemap style.
#' Spatial data that are too large will trigger an error, and should be added
#' to the style in Mapbox Studio instead.
#' @param overlay_style A named list of vectors specifying how to style the sf
#' overlay. Possible names are "stroke", "stroke-width" (or "stroke_width"),
#' "stroke-opacity" (or "stroke_opacity"), "fill", and "fill-opacity" (or
#' "fill_opacity"). The fill and stroke color values can be specified as
#' six-digit hex codes or color names, and the opacity and width values should
#' be supplied as floating-point numbers. If overlay_style is `NULL`, the
#' style values can be pulled from columns with the same names in
#' `overlay_sf`.
#' @param overlay_markers The prepared overlay markers (optional). See the
#' function [prep_overlay_markers] for more information on how to specify a
#' marker overlay.
#' @param longitude,latitude The longitude and latitude of the map center. If an
#' overlay is supplied, the map will default to the extent of the overlay
#' unless longitude, latitude, and zoom are all specified.
#' @param zoom The map zoom. The map will infer this from the overlay unless
#' longitude, latitude, and zoom are all specified.
#' @param width,height The map width and height; defaults to `NULL`
#' @param pitch,bearing The map pitch and bearing; defaults to `NULL`. pitch can
#' range from 0 to 60, and bearing from -360 to 360.
#' @param scale ratio to scale the output image; `scale = 1` will return the
#' largest possible image. defaults to 0.5
#' @param scaling_factor The scaling factor of the tiles; either `"1x"`
#' (the default) or `"2x"`
#' @param attribution Controls whether there is attribution on the image.
#' Defaults to `TRUE`. If `FALSE`, the watermarked attribution is removed from
#' the image. You still have a legal responsibility to attribute maps that use
#' OpenStreetMap data, which includes most maps from Mapbox. If you specify
#' `attribution = FALSE`, you are legally required to include proper
#' attribution elsewhere on the webpage or document.
#' @param logo Controls whether there is a Mapbox logo on the image. Defaults to
#' `TRUE`.
#' @param before_layer A character string that specifies where in the hierarchy
#' of layer elements the overlay should be inserted. The overlay will be
#' placed just above the specified layer in the given Mapbox styles. List
#' layer ids for a map style with `get_style(style_id = style_id, username =
#' username, style_url = style_url, access_token =
#' access_token)[["layers"]][["id"]]`
#' @param access_token A Mapbox access token; which can be set with
#' [mb_access_token].
#' @param image If `FALSE`, return the a [httr::response] object from
#' [httr::GET] using the static image URL; defaults to `TRUE`.
#' @param strip If `TRUE`, drop image comments and metadata when `image = TRUE`;
#' defaults to `TRUE`.
#' @return A pointer to an image of class `"magick-image"` if `image = TRUE`.
#' The resulting image can be manipulated further with functions from the
#' magick package.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#'
#' points_of_interest <- tibble::tibble(
#' longitude = c(-73.99405, -74.00616, -73.99577, -74.00761),
#' latitude = c(40.72033, 40.72182, 40.71590, 40.71428)
#' )
#'
#' prepped_pois <- prep_overlay_markers(
#' data = points_of_interest,
#' marker_type = "pin-l",
#' label = 1:4,
#' color = "fff"
#' )
#'
#' map <- static_mapbox(
#' style_id = "streets-v11",
#' username = "mapbox",
#' overlay_markers = prepped_pois,
#' width = 1200,
#' height = 800
#' )
#'
#' map
#' }
#'
#' @export
#' @importFrom httr GET content
#' @importFrom jsonlite fromJSON
#' @importFrom magick image_read
static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
longitude = NULL,
latitude = NULL,
zoom = NULL,
width = NULL,
height = NULL,
bearing = NULL,
pitch = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
image = TRUE,
strip = TRUE) {
access_token <- get_mb_access_token(access_token)
base <-
set_static_map_style(
style_url = style_url,
username = username,
style_id = style_id
)
# Next, figure out the overlay
# Basically, the idea is that you can string together GeoJSON, markers, etc.
# on a map and put it over a Mapbox style. overlay should accept such
# components and format them accordingly.
#
# `overlay_sf` converts to GeoJSON to make the request.
# The input GeoJSON should have internal information conforming to
# simplestyle-spec Eventually, this function could be able to do that
# internally but not yet
base <-
set_static_map_overlay(
base = base,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers
)
merc_bbox <- location_to_bbox(location, buffer_dist, units, crs = 3857)
lonlat_bbox <- location_to_bbox(location, buffer_dist, units, crs = 4326)
focus_args <- c(longitude, latitude, zoom)
if (all(is.null(focus_args))) {
if (is.null(location)) {
focus <- "auto"
} else {
focus <- paste0("[", paste0(lonlat_bbox, collapse = ","), "]")
}
} else {
if (!is.null(location) && all(sapply(c(longitude, latitude), is.null))) {
center <- bbox_to_center(lonlat_bbox, crs = 4326)
longitude <- center[1]
latitude <- center[2]
}
if (is.null(zoom)) {
zoom <- 11
}
stopifnot(
"`zoom` must be between 0 and 22" = (zoom >= 0) && (zoom <= 22)
)
focus_args <- c(longitude, latitude, zoom)
stopifnot(
all(!is.null(focus_args))
)
if (is.null(bearing)) {
bearing <- 0
} else if ((bearing < 0) && (bearing >= -360)) {
bearing <- 360 + bearing
}
if (is.null(pitch)) {
pitch <- 0
}
stopifnot(
"`bearing` must be between -360 and 360" = ((bearing >= 0) && (bearing <= 360)),
"`pitch` must be between 0 and 60" = ((pitch >= 0) && (pitch <= 60))
)
focus_args <- c(focus_args, bearing, pitch)
focus <- paste0(focus_args, collapse = ",")
}
base <- paste(base, focus, sep = "/")
base1 <-
set_static_map_dims(
base = base,
bbox = merc_bbox,
width = width,
height = height,
scale = scale
)
scaling_factor <- match.arg(scaling_factor)
if (scaling_factor == "2x") {
base1 <- sprintf("%s@2x", base1)
}
if (nchar(base1) > 8192) {
stop("Your request is too large likely due to the size of your overlay
geometry. Consider simplifying your overlay geometry or adding your
data to a style in Mapbox Studio to resolve this.", call. = FALSE)
}
if (!is.null(before_layer)) {
before_layer <-
match.arg(
before_layer,
get_style(
style_id = style_id,
username = username,
style_url = style_url,
access_token = access_token
)[["layers"]][["id"]]
)
}
request <-
httr::GET(
base1,
query = list(
access_token = access_token,
attribution = tolower(attribution),
logo = tolower(logo),
before_layer = before_layer
)
)
if (request$status_code != 200) {
content <- httr::content(request, as = "text")
stop(print(jsonlite::fromJSON(content)), call. = FALSE)
}
if (!image) {
return(request)
}
if (!rlang::is_installed("magick") && rlang::is_interactive()) {
rlang::check_installed("magick")
}
magick::image_read(httr::content(request), strip = strip)
}
#' Add username and style_id to API query for static_mapbox
#'
#' @noRd
#' @importFrom stringi stri_extract
set_static_map_style <- function(style_url = NULL, username, style_id) {
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url,
regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url,
regex = paste0("(?<=", username, "/).+"))
}
# Construct the request URL
# First, do chunk 1
base <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/static",
username, style_id
)
return(base)
}
#' Add overlay to API query for static_mapbox
#'
#' @noRd
#' @importFrom sf st_sf
#' @importFrom utils URLencode
#' @importFrom geojsonsf sf_geojson
set_static_map_overlay <- function(base = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL) {
overlay <- NULL
if (!is.null(overlay_sf)) {
if (is_sfc(overlay_sf)) {
overlay_sf <- sf::st_sf(overlay_sf)
}
overlay_sf <-
set_overlay_style(
overlay_sf = overlay_sf,
overlay_style = overlay_style
)
if (sf::st_crs(overlay_sf)["input"] != "EPSG:4326") {
overlay_sf <- sf::st_transform(overlay_sf, 4326)
}
overlay_json <- geojsonsf::sf_geojson(overlay_sf)
overlay <- sprintf("geojson(%s)", overlay_json)
}
if (!is.null(overlay_markers)) {
if (attr(overlay_markers, "mapboxapi") != "marker_spec") {
stop("Overlay markers should be formatted with `prep_overlay_markers()`
before using in a static map", call. = FALSE)
}
marker_spec <- overlay_markers %>%
unlist() %>%
paste0(collapse = ",")
if (!is.null(overlay)) {
overlay <- paste(overlay, marker_spec, sep = ",")
} else {
overlay <- marker_spec
}
}
if (!is.null(overlay)) {
return(paste(base, overlay, sep = "/"))
}
base
}
#' Set overlay style
#'
#' @noRd
#' @importFrom utils URLencode
set_overlay_style <-
function(overlay_sf,
overlay_style = NULL) {
if (is.null(overlay_style)) {
overlay_style <- overlay_sf[1, ]
}
style_names <- names(overlay_style)
if ("stroke" %in% style_names) {
if (!is_hex(overlay_style$stroke)) {
overlay_style$stroke <- col2hex(overlay_style$stroke)
}
overlay_sf$stroke <-
utils::URLencode(overlay_style$stroke, reserved = TRUE)
}
if ("stroke-opacity" %in% style_names) {
overlay_sf$`stroke-opacity` <-
utils::URLencode(
as.character(overlay_style$`stroke-opacity`),
reserved = TRUE
)
}
if ("stroke_opacity" %in% style_names) {
overlay_sf$`stroke-opacity` <-
utils::URLencode(
as.character(overlay_style$stroke_opacity),
reserved = TRUE
)
}
if ("stroke-width" %in% style_names) {
overlay_sf$`stroke-width` <-
utils::URLencode(
as.character(overlay_style$`stroke-width`),
reserved = TRUE
)
}
if ("stroke_width" %in% style_names) {
overlay_sf$`stroke-width` <-
utils::URLencode(
as.character(overlay_style$stroke_width),
reserved = TRUE
)
}
if ("fill" %in% style_names) {
if (!is_hex(overlay_style$fill)) {
overlay_style$fill <- col2hex(overlay_style$fill)
}
overlay_sf$fill <-
utils::URLencode(overlay_style$fill, reserved = TRUE)
}
if ("fill_opacity" %in% style_names) {
overlay_sf$`fill-opacity` <-
utils::URLencode(
as.character(overlay_style$fill_opacity),
reserved = TRUE
)
}
if ("fill-opacity" %in% style_names) {
overlay_sf$`fill-opacity` <-
utils::URLencode(
as.character(overlay_style$`fill-opacity`),
reserved = TRUE
)
}
overlay_sf
}
#' Add width/height to API query for static_mapbox
#'
#' @noRd
set_static_map_dims <- function(base = NULL,
bbox = NULL,
width = NULL,
height = NULL,
scale = 0.5) {
has_map_dims <- !all(is.null(c(width, height)))
if (!has_map_dims && !is.null(bbox)) {
asp <- as.numeric(abs(bbox$xmax - bbox$xmin) / abs(bbox$ymax - bbox$ymin))
max_size <- min(1280, round(1280 * scale))
width <- min(max_size, round(max_size * asp))
height <- min(max_size, round(max_size / asp))
} else if (has_map_dims) {
width <- round(width)
height <- round(height)
}
sprintf("%s/%sx%s", base, width, height)
}
#' Make a static Mapbox ggplot2 layer or tmap basemap
#'
#' These functions wrap [static_mapbox()] and [ggspatial::layer_spatial()] or
#' [tmap::tm_rgb()] to support the use of images from the [Mapbox Static Maps
#' API](https://www.mapbox.com/static-maps) as
#' [{ggplot2}](https://ggplot2.tidyverse.org/) or
#' [{tmap}](https://r-tmap.github.io/tmap/) basemaps.
#'
#' This function uses a different approach than [get_static_tiles()]. Instead,
#' [layer_static_mapbox()] is based largely on `layer_mapbox()` in the snapbox package
#' (available under a [MIT
#' license](https://github.com/anthonynorth/snapbox/blob/master/LICENSE). There
#' are a few key differences between [layer_static_mapbox()] and
#' `layer_mapbox()`. The "scale" parameter is equivalent to the
#' "scale_ratio" parameter for snapbox. Setting `scale_factor = "2x"` is
#' equivalent to setting `retina = TRUE.` Both functions return basemaps that
#' are no larger than a single tile (a maximum of 1280 by 1280 pixels).
#'
#' For [tm_static_mapbox()], [tmap::tm_shape] is called with `projection = 3857` and
#' [tmap::tm_rgb] is called with `max.value = 1`.
#'
#' @rdname layer_static_mapbox
#' @inheritParams static_mapbox
#' @param ... additional parameters passed to [ggspatial::layer_spatial] or [tmap::tm_rgb]
#' @export
#' @author Eli Pousson, \email{eli.pousson@gmail.com}
#' @author Anthony North, \email{anthony.jl.north@gmail.com}
#' @author Miles McBain, \email{miles.mcbain@gmail.com}
#' @importFrom rlang is_installed is_interactive check_installed
layer_static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
width = NULL,
height = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
...) {
if (!rlang::is_installed("ggspatial") && rlang::is_interactive()) {
rlang::check_installed("ggspatial")
}
request <-
static_mapbox(
location = location,
buffer_dist = buffer_dist,
units = units,
style_id = style_id,
username = username,
style_url = style_url,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers,
width = width,
height = height,
scale = scale,
scaling_factor = scaling_factor,
attribution = attribution,
logo = logo,
before_layer = before_layer,
access_token = access_token,
image = FALSE
)
ras <- request_to_raster(request, location, buffer_dist, units)
ggspatial::layer_spatial(data = ras, ...)
}
#' @name tm_static_mapbox
#' @rdname layer_static_mapbox
#' @inheritParams static_mapbox
#' @importFrom rlang is_installed is_interactive check_installed
#' @export
tm_static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
width = NULL,
height = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
...) {
if (!rlang::is_installed("tmap") && rlang::is_interactive()) {
rlang::check_installed("tmap")
}
request <-
static_mapbox(
location = location,
buffer_dist = buffer_dist,
units = units,
style_id = style_id,
username = username,
style_url = style_url,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers,
width = width,
height = height,
scale = scale,
scaling_factor = scaling_factor,
attribution = attribution,
logo = logo,
before_layer = before_layer,
access_token = access_token,
image = FALSE
)
ras <- request_to_raster(request, location, buffer_dist, units)
tmap::tm_shape(shp = ras, projection = 3857) +
tmap::tm_rgb(max.value = 1, ...)
}
#' Convert static_mapbox API request to raster image
#'
#' @noRd
#' @importFrom sf st_crs
#' @importFrom raster brick extent projection
#' @importFrom httr content
request_to_raster <- function(request,
location = NULL,
buffer_dist = NULL,
units = "m") {
ras <- raster::brick(httr::content(request))
merc_bbox <- location_to_bbox(location, buffer_dist, units, crs = 3857)
merc_proj <- sf::st_crs(3857)$proj4string
raster::extent(ras) <- merc_bbox
suppressWarnings(raster::projection(ras) <- merc_proj)
ras
}
#' Prepare overlay markers for use in a Mapbox static map
#'
#' Markers are prepared to match GeoJSON
#' [marker-spec](https://github.com/mapbox/mapbox-gl-markers#geojson-marker-spec)
#' which is a partial implementation of the GeoJSON
#' [simplestyle-spec](https://github.com/mapbox/simplestyle-spec/tree/master/1.1.0)
#' (described as a work-in-progress by Mapbox).
#'
#' @param data An input data frame with longitude and latitude columns (X and Y
#' or lon and lat as names are also acceptable) or an `sf` object with
#' geometry type POINT.
#' @param marker_type The marker type; one of `"pin-s"`, for a small pin;
#' `"pin-l"`, for a large pin; and `"url"`, for an image path. If
#' marker_type is the same length as the rows in data, a mix of different
#' marker types are allowed.
#' @param label The marker label (optional). Can be a letter, number (0 through
#' 99), or a valid Maki icon (see <https://labs.mapbox.com/maki-icons/>)
#' for options).
#' @param color The marker color (optional). `color` can be specified as a color
#' name or as a three or six-digit hexadecimal code (with or without the
#' number sign).
#' @param longitude A vector of longitudes; inferred from the input dataset if
#' `data` is provided.
#' @param latitude A vector of latitudes; inferred from the input dataset if
#' `data` is provided.
#' @param url The URL of the image to be used for the icon if `marker_type =
#' "url"`.
#' @name prep_overlay_markers
#' @return A formatted list of marker specifications that can be passed to the
#' [static_mapbox] function.
#' @export
#' @importFrom sf st_geometry_type st_point_on_surface st_transform
#' st_coordinates
#' @importFrom purrr map
prep_overlay_markers <- function(data = NULL,
marker_type = c("pin-s", "pin-l", "url"),
label = NA,
color = NA,
longitude = NULL,
latitude = NULL,
url = NA) {
if (!is.null(data)) {
if (any(grepl("^sf", class(data)))) {
if (sf::st_geometry_type(data, by_geometry = FALSE) != "POINT") {
data <- suppressWarnings(sf::st_point_on_surface(data))
}
# Construct the marker data frame
coords_df <- data %>%
sf::st_transform(4326) %>%
sf::st_coordinates() %>%
as.data.frame()
coords_df <- cbind(data, coords_df)
} else {
coords_df <- data
}
# Infer coordinates from column names
names(coords_df) <- tolower(names(coords_df))
if (all(c("lon", "lat") %in% names(coords_df))) {
coords_df$longitude <- coords_df$lon
coords_df$latitude <- coords_df$lat
} else if (all(c("x", "y") %in% names(coords_df))) {
coords_df$longitude <- coords_df$x
coords_df$latitude <- coords_df$y
}
if (!all(c("longitude", "latitude") %in% names(coords_df))) {
stop("Your input dataset must have longitude/latitude information denoted
by columns x and y, lon and lat, or longitude and latitude.",
call. = FALSE
)
}
if ("marker_type" %in% names(coords_df)) {
marker_type <- coords_df$marker_type
} else {
marker_type <-
match.arg(
marker_type, c("pin-s", "pin-l", "url"),
several.ok = length(marker_type) == nrow(coords_df)
)
coords_df$marker_type <- marker_type
}
if ("label" %in% names(coords_df)) {
label <- coords_df$label
} else {
if (!is.null(label)) {
coords_df$label <- label
}
}
if ("color" %in% names(coords_df)) {
color <- coords_df$color
} else {
if (!is.null(color)) {
coords_df$color <- color
}
}
if (!all(is.null(coords_df$color))) {
if (!is_hex(coords_df$color)) {
coords_df$color <- col2hex(coords_df$color, TRUE)
} else {
coords_df$color <- rmv_hash(coords_df$color)
}
}
if ("url" %in% names(coords_df)) {
url <- coords_df$url
} else {
if (!is.null(url)) {
coords_df$url <- url
}
}
} else {
if (!is.null(color)) {
if (!is_hex(color)) {
color <- col2hex(color, TRUE)
} else {
color <- rmv_hash(color)
}
}
coords_df <-
data.frame(
longitude = longitude,
latitude = latitude,
marker_type = marker_type,
label = label,
color = color,
url = url
)
}
# Iterate through the coords_df to make a formatted list of markers
marker_list <- purrr::map(1:nrow(coords_df), ~ {
format_marker(.x, coords_df = coords_df, url = url)
})
attr(marker_list, "mapboxapi") <- "marker_spec"
marker_list
}
#' Format marker using marker_spec based on n row of a coordinate data frame
#'
#' @noRd
#' @importFrom utils URLencode
format_marker <- function(n, coords_df = NULL, url = NULL) {
r <- coords_df[n, ]
if (r$marker_type %in% c("pin-s", "pin-l")) {
if (!is.na(r$label) && !is.na(r$color)) {
return(sprintf(
"%s-%s+%s(%s,%s)",
r$marker_type,
tolower(r$label),
r$color,
r$longitude,
r$latitude
))
} else if (is.na(r$label) && !is.na(r$color)) {
return(sprintf(
"%s-%s(%s,%s)",
r$marker_type,
r$color,
r$longitude,
r$latitude
))
} else if (!is.na(r$label) && is.na(r$color)) {
return(sprintf(
"%s-%s(%s,%s)",
r$marker_type,
tolower(r$label),
r$longitude,
r$latitude
))
} else {
return(sprintf(
"%s-(%s,%s)",
r$marker_type,
r$longitude,
r$latitude
))
}
} else if (r$marker_type == "url") {
if (is.null(url)) {
stop("A valid URL must be provided.")
}
encoded_url <- utils::URLencode(r$url, reserved = TRUE)
return(sprintf(
"url-%s(%s,%s)",
encoded_url,
r$longitude,
r$latitude
))
}
}
#' Use a Mapbox style in a Leaflet map
#'
#' See the [Mapbox Static Tiles API
#' documentation](https://docs.mapbox.com/api/maps/static-tiles/) for more
#' information.
#'
#' @param map A map widget object created by [leaflet::leaflet()]
#' @param style_url A Mapbox style URL
#' @param style_id The style ID of a Mapbox style
#' @param username A Mapbox username
#' @param scaling_factor The scaling factor to use when rendering the tiles. A
#' scaling factor of `"1x"` (the default) returns 512px by 512px tiles. A
#' factor of `"1x"` returns 256x256 tiles, and a factor of `"2x"` returns
#' 1024x1024 tiles.
#' @param access_token Your Mapbox access token; which can be set with
#' [mb_access_token()].
#' @param layerId the layer ID
#' @param group The name of the group the Mapbox tile layer should belong to
#' (for use in Shiny and to modify layers control in a Leaflet workflow)
#' @param options A list of extra options (optional)
#' @param data The data object used to derive argument values; can be provided
#' to the initial call to [leaflet::leaflet()]
#' @param attribution If `TRUE`, pass a standard attribution to
#' [leaflet::addTiles()]. If `FALSE`, attribution is `NULL`. attribution can
#' also be a character string including HTML.
#' @return A pointer to the Mapbox Static Tiles API which will be translated
#' appropriately by the leaflet R package.
#'
#' @examples \dontrun{
#'
#' library(leaflet)
#' library(mapboxapi)
#'
#' leaflet() %>%
#' addMapboxTiles(
#' style_id = "light-v9",
#' username = "mapbox"
#' ) %>%
#' setView(
#' lng = -74.0051,
#' lat = 40.7251,
#' zoom = 13
#' )
#' }
#'
#' @export
addMapboxTiles <- function(map,
style_id,
username,
style_url = NULL,
scaling_factor = c("1x", "0.5x", "2x"),
access_token = NULL,
layerId = NULL,
group = NULL,
options = leaflet::tileOptions(),
data = leaflet::getMapData(map),
attribution = TRUE) {
access_token <- get_mb_access_token(access_token)
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url, regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url, regex = paste0("(?<=", username, "/).+"))
}
sfactor <- match.arg(scaling_factor)
url <-
switch(sfactor,
"1x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/{z}/{x}/{y}?access_token=%s", username, style_id, access_token),
"0.5x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/256/{z}/{x}/{y}?access_token=%s", username, style_id, access_token),
"2x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/{z}/{x}/{y}@2x?access_token=%s", username, style_id, access_token)
)
if (!is.character(attribution)) {
if (attribution) {
attribution <- '© <a href="https://www.mapbox.com/about/maps/">Mapbox</a> © <a href="http://www.openstreetmap.org/copyright">OpenStreetMap</a> <strong><a href="https://www.mapbox.com/map-feedback/" target="_blank">Improve this map</a></strong>'
} else {
attribution <- NULL
}
}
leaflet::addTiles(
map = map,
urlTemplate = url,
attribution = attribution,
layerId = layerId,
group = group,
options = options,
data = data
)
}
#' Get static tiles from a Mapbox style for use as a basemap
#'
#' This function queries the [Mapbox Static Tiles
#' API](https://docs.mapbox.com/api/maps/static-tiles/) and composites the tiles
#' as a raster suitable for use as a basemap in
#' [tmap](https://r-tmap.github.io/tmap/) or
#' [ggplot2](https://ggplot2.tidyverse.org/) (with the
#' [ggspatial::layer_spatial()] function. It returns a raster
#' layer that corresponds either to an input bounding box or a buffered area
#' around an input shape.
#'
#' @param location An input location for which you would like to request tiles.
#' Can be a length-4 vector representing a bounding box, or an `sf` object.
#' If an input `sf` object is supplied, use the `buffer_dist` argument to
#' control how much area you want to capture around the layer.
#' While the input `sf` object can be in an arbitrary coordinate reference system,
#' if a length-4 bounding box vector is supplied instead it must represent
#' WGS84 longitude/latitude coordinates and be in the order
#' `c(xmin, ymin, xmax, ymax)`.
#' @param zoom The zoom level for which you'd like to return tiles.
#' @param style_id A Mapbox style ID; retrieve yours from your Mapbox account.
#' @param username A Mapbox username.
#' @param style_url A Mapbox style URL.
#' @param scaling_factor The scaling factor to use; one of `"1x"` or `"2x"`.
#' @param buffer_dist The distance to buffer around an input `sf` object for determining tile extent, specified in units. Defaults to 5000.
#' @param units Units of `buffer_dist`; defaults to "m" (meters). If buffer_dist
#' is a units class object, the units argument is ignored.
#' @param crop Whether or not to crop the result to the specified bounding box or buffer area.
#' Defaults to `TRUE`; `FALSE` will return the extent of the overlapping
#' tiles.
#' @param access_token A Mapbox access token. Supply yours here or set globally with the [mb_access_token()] function.
#'
#' @return A raster layer of tiles from the requested Mapbox style representing the area around the input location. The raster layer is projected in the Web Mercator coordinate reference system.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#' library(tigris)
#' library(tmap)
#' library(ggspatial)
#' library(ggplot2)
#'
#' ny_tracts <- tracts("NY", "New York", cb = TRUE)
#'
#' ny_tiles <- get_static_tiles(
#' location = ny_tracts,
#' zoom = 10,
#' style_id = "light-v9",
#' username = "mapbox"
#' )
#'
#' # tmap usage:
#' tm_shape(ny_tiles) +
#' tm_rgb() +
#' tm_shape(ny_tracts) +
#' tm_polygons(alpha = 0.5, col = "navy") +
#' tm_credits("Basemap (c) Mapbox, (c) OpenStreetMap",
#' position = c("RIGHT", "BOTTOM")
#' )
#'
#' # ggplot2 usage:
#' ggplot() +
#' layer_spatial(ny_tiles) +
#' geom_sf(data = ny_tracts, fill = "navy", alpha = 0.5) +
#' theme_void() +
#' labs(caption = "Basemap (c) Mapbox, (c) OpenStreetMap")
#' }
#'
#' @export
get_static_tiles <- function(location,
zoom,
style_id,
username,
style_url = NULL,
scaling_factor = c("1x", "2x"),
buffer_dist = 5000,
units = "m",
crop = TRUE,
access_token = NULL) {
message("Attribution is required if using Mapbox tiles on a map.\nAdd the text '(c) Mapbox, (c) OpenStreetMap' to your map for proper attribution.")
access_token <- get_mb_access_token(access_token)
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url, regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url, regex = paste0("(?<=", username, "/).+"))
}
bbox <- location_to_bbox(location, buffer_dist, units)
tile_grid <- slippymath::bbox_to_tile_grid(bbox = bbox, zoom = zoom)
tile_ids <- tile_grid$tiles
sfactor <- match.arg(scaling_factor)
tile_list <- purrr::map2(tile_ids$x, tile_ids$y, ~ {
# Build the request to Mapbox
if (sfactor == "2x") {
url <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/tiles/%s/%s/%s@2x",
username, style_id, zoom, .x, .y
)
} else {
url <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/tiles/%s/%s/%s",
username, style_id, zoom, .x, .y
)
}
box <- slippymath::tile_bbox(.x, .y, zoom)
tmp <- tempdir()
loc <- file.path(tmp, sprintf("%s_%s.png", .x, .y))
request <- httr::GET(url,
query = list(access_token = access_token),
httr::write_disk(loc, overwrite = TRUE)
)
# Only try to read the data if there is data available
if (request$status_code == 200) {
# Most styles will be returned as PNG as they are composed entirely
# of vector layers. However, if a style includes satellite imagery it will
# be returned as JPEG. Check this at this step.
my_img <- try(png::readPNG(loc), silent = TRUE)
if ("try-error" %in% class(my_img)) {
my_img <- jpeg::readJPEG(loc)
}
my_img <- my_img * 255
merc <- sf::st_crs(3857)$proj4string
ras <- raster::brick(my_img)
raster::extent(ras) <- box
suppressWarnings(raster::projection(ras) <- merc)
return(ras)
}
})
# Assemble the list of raster tiles
# Adapted from Michael Sumner's ceramic code: https://github.com/hypertidy/ceramic/blob/master/R/raster.R
if (length(tile_list) == 1) {
out_brick <- tile_list[[1]]
} else {
target_crs <- suppressWarnings(raster::projection(tile_list[[1]]))
out_raster <- suppressWarnings(tile_list %>%
purrr::map(function(tile) {
raster::extent(tile)
}) %>%
purrr::reduce(raster::union) %>%
raster::raster(crs = target_crs))
raster::res(out_raster) <- suppressWarnings(raster::res(tile_list[[1]]))
raster_cells <- suppressWarnings(tile_list %>%
map(function(tile) {
raster::cellsFromExtent(out_raster, tile)
}) %>%
unlist(use.names = FALSE))
raster_values <- suppressWarnings(tile_list %>%
map(function(tile) {
raster::values(tile)
}) %>%
reduce(rbind))
out_brick <- suppressWarnings(raster::brick(out_raster, out_raster, out_raster) %>%
raster::setValues(raster_values[order(raster_cells), ]))
}
if (crop) {
bb_shape <- bbox %>%
sf::st_as_sfc(crs = 4326) %>%
sf::st_sf() %>%
sf::st_transform(sf::st_crs(out_brick))
cropped_brick <- raster::crop(out_brick, bb_shape)
return(cropped_brick)
} else {
return(out_brick)
}
}
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Defines functions get_vector_tiles query_tiles check_upload_status upload_tiles
Documented in check_upload_status get_vector_tiles query_tiles upload_tiles
#' Upload dataset to your Mapbox account
#'
#' @param input An `sf` object, or the path to the dataset to upload as a
#' character string.
#' @param username Your Mapbox username
#' @param access_token Your Mapbox access token; must have secret scope
#' @param tileset_id The ID of the tileset in your Mapbox account
#' @param tileset_name The name of the tileset in your Mapbox account
#' @param keep_geojson Whether or not to keep the temporary GeoJSON used to
#' generate the tiles (if the input is an `sf` object)
#' @param multipart Whether or not to upload to the temporary AWS staging bucket
#' as a multipart object; defaults to `FALSE`.
#'
#' @examples \dontrun{
#'
#' # Example: create a tileset of median age for all United States Census tracts
#' # Requires setting a Mapbox secret access token as an environment variable
#'
#' library(mapboxapi)
#' library(tidycensus)
#' options(tigris_use_cache = TRUE)
#'
#' median_age <- get_acs(
#' geography = "tract",
#' variables = "B01002_001",
#' state = c(state.abb, "DC"),
#' geometry = TRUE
#' )
#'
#' upload_tiles(
#' input = median_age,
#' username = "kwalkertcu", # Your username goes here
#' tileset_id = "median_age",
#' tileset_name = "us_median_age_2014_to_2018"
#' )
#' }
#'
#' @export
upload_tiles <- function(input,
username,
access_token = NULL,
tileset_id = NULL,
tileset_name = NULL,
keep_geojson = FALSE,
multipart = FALSE) {
access_token <- get_mb_access_token(access_token, secret_required = TRUE)
# Allow input to be an `sf` object
if (any(grepl("^sf", class(input)))) {
input <- sf::st_transform(input, 4326)
if (is.null(tileset_name)) {
layer_name <- stringi::stri_rand_strings(1, 6)
} else {
layer_name <- tileset_name
}
if (keep_geojson) {
outfile <- paste0(layer_name, ".geojson")
path <- file.path(dir, outfile)
sf::st_write(input, path, quiet = TRUE)
} else {
tmp <- tempdir()
tempfile <- paste0(layer_name, ".geojson")
path <- file.path(tmp, tempfile)
sf::st_write(input, path, quiet = TRUE)
}
} else {
path <- input
}
# If tileset_id is NULL, use the basename of the input
if (is.null(tileset_id)) {
tileset_id <- gsub("\\.[^.]*$", "", basename(path))
}
# Get AWS credentials
base1 <- sprintf(
"https://api.mapbox.com/uploads/v1/%s/credentials",
username
)
req <- httr::POST(base1, query = list(access_token = access_token))
credentials <- httr::content(req, as = "text") %>%
jsonlite::fromJSON()
# Use these credentials to transfer to the staging bucket
aws.s3::put_object(
file = path,
object = credentials$key,
bucket = credentials$bucket,
region = "us-east-1",
key = credentials$accessKeyId,
secret = credentials$secretAccessKey,
session_token = credentials$sessionToken,
check_region = FALSE,
multipart = multipart
)
# Once done, generate the upload
url <- sprintf(
"http://%s.s3.amazonaws.com/%s",
credentials$bucket,
credentials$key
)
if (is.null(tileset_name)) {
upload <- sprintf(
'{"url": "%s", "tileset": "%s.%s"}',
url, username, tileset_id
)
} else {
upload <- sprintf(
'{"url": "%s", "tileset": "%s.%s", "name": "%s"}',
url, username, tileset_id, tileset_name
)
}
base2 <- sprintf(
"https://api.mapbox.com/uploads/v1/%s",
username
)
request <- httr::POST(base2,
httr::add_headers(
"Content-Type" = "application/json",
"Cache-Control" = "no-cache"
),
body = upload,
query = list(access_token = access_token)
)
response <- request %>%
httr::content(as = "text") %>%
jsonlite::fromJSON()
if (request$status_code != "201") {
stop(sprintf("Upload failed: your error message is %s", response),
call. = FALSE
)
}
message(sprintf("Your upload ID is %s", response$id))
}
#' Check the status of a Mapbox upload
#'
#' @param upload_id The upload ID
#' @param username Your account's username
#' @param access_token Your Mapbox access token
#'
#' @export
check_upload_status <- function(upload_id,
username,
access_token = NULL) {
access_token <-
get_mb_access_token(
access_token,
default = "MAPBOX_SECRET_TOKEN",
secret_required = TRUE
)
status <- httr::GET(
sprintf(
"https://api.mapbox.com/uploads/v1/%s/%s",
username, upload_id
),
query = list(access_token = access_token)
)
status %>%
httr::content(as = "text") %>%
jsonlite::fromJSON()
}
#' Get information about features in a tileset using the Tilequery API
#'
#' @param location The location for which you'd like to query tiles, expressed
#' as either a length-2 vector of longitude and latitude or an address you'd
#' like to geocode.
#' @param tileset_id The tileset ID to query.
#' @param radius The radius around the point (in meters) for which you'd like to
#' query features. For point-in-polygon queries (e.g. "what county is my point
#' located in?") the default of 0 should be used.
#' @param limit How many features to return (defaults to 5). Can be an integer
#' between 1 and 50.
#' @param dedupe Whether or not to return duplicate features as identified by
#' their IDs. The default, TRUE, will de-duplicate your dataset.
#' @param geometry The feature geometry type to query - can be `"point"`,
#' `"linestring"`, or `"polygon"`. If left blank, all geometry types
#' will be queried.
#' @param layers A vector of layer IDs you'd like to query (recommended); if
#' left blank will query all layers, with the limitation that at most 50
#' features can be returned.
#' @param access_token A Mapbox access token, which can be set with
#' [mb_access_token()].
#'
#' @return An R list containing the API response, which includes information
#' about the requested features. Parse the list to extract desired elements.
#' @seealso
#' <https://docs.mapbox.com/help/tutorials/find-elevations-with-tilequery-api/>
#'
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#'
#' elevation <- query_tiles(
#' location = "Breckenridge, Colorado",
#' tileset_id = "mapbox.mapbox-terrain-v2",
#' layer = "contour",
#' limit = 50
#' )
#'
#' max(elevation$features$properties$ele)
#' }
#'
#' @export
query_tiles <- function(location,
tileset_id,
radius = 0,
limit = 5,
dedupe = TRUE,
geometry = NULL,
layers = NULL,
access_token = NULL) {
access_token <- get_mb_access_token(access_token)
# If location is an address, geocode it
if (length(location) == 1) {
coords <- mb_geocode(location, access_token = access_token)
} else if (length(location) == 2) {
coords <- location
} else {
stop("The specified location must either be a
coordinate pair or a valid address",
call. = FALSE
)
}
# Format the requested layers if included
if (!is.null(layers)) {
layers <- paste0(layers, collapse = ",")
}
# Format the dedupe param
if (dedupe) {
dedupe <- "true"
} else {
dedupe <- "false"
}
# Construct the JSON for the request
base <- sprintf(
"https://api.mapbox.com/v4/%s/tilequery/%s,%s.json",
tileset_id, coords[1], coords[2]
)
# Build the request
query <- httr::GET(base, query = list(
radius = radius,
limit = limit,
dedupe = dedupe,
geometry = geometry,
layers = layers,
access_token = access_token
))
content <- httr::content(query, as = "text")
if (query$status_code != 200) {
pull <- jsonlite::fromJSON(content)
stop(pull$message, call. = FALSE)
}
result <- jsonlite::fromJSON(content)
return(result)
}
#' Retrieve vector tiles from a given Mapbox tileset
#'
#' @param tileset_id The name of the tileset ID; names can be retrieved from
#' your Mapbox account
#' @param location The location for which you'd like to retrieve tiles. If the
#' input is an `sf` object, the function will return data for all tiles that
#' intersect the object's bounding box. If the input is a coordinate pair or
#' an address, data will be returned for the specific tile that contains the
#' input.
#' @param zoom The zoom level of the request; larger zoom levels will return
#' more detail but will take longer to process.
#' @param access_token A Mapbox access token; which can be set with
#' [mb_access_token()].
#'
#' @return A list of `sf` objects representing the different layer types found
#' in the requested vector tiles.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#' library(ggplot2)
#'
#' vector_extract <- get_vector_tiles(
#' tileset_id = "mapbox.mapbox-streets-v8",
#' location = c(-73.99405, 40.72033),
#' zoom = 15
#' )
#'
#' ggplot(vector_extract$building$polygons) +
#' geom_sf() +
#' theme_void()
#' }
#'
#' @export
get_vector_tiles <- function(tileset_id,
location,
zoom,
access_token = NULL) {
access_token <- get_mb_access_token(access_token)
# If location is an `sf` object, get the bbox and the tiles that intersect it
if (any(grepl("^sf", class(location)))) {
bbox <- location %>%
sf::st_transform(4326) %>%
sf::st_bbox(.)
tile_grid <- slippymath::bbox_to_tile_grid(bbox = bbox, zoom = zoom)
tile_ids <- tile_grid$tiles
message(sprintf("Requesting data for %s map tiles. To speed up your query
choose a smaller extent or zoom level.", nrow(tile_ids)))
sf_list <- purrr::map2(tile_ids$x, tile_ids$y, ~ {
# Build the request to Mapbox
url <- sprintf(
"https://api.mapbox.com/v4/%s/%s/%s/%s.mvt",
tileset_id, zoom, .x, .y
)
request <- httr::GET(url, query = list(access_token = access_token))
# if (request$status_code != 200) {
# content <- httr::content(request, as = "text")
# stop(print(content$message), call. = FALSE)
# }
# Only try to read the data if there is data available
if (request$status_code == 200) {
sf_output <- protolite::read_mvt_sf(request$url)
return(sf_output)
}
})
# Now, combine the internal list elements by name
# First, find the tile with the most elements and get the names
max_ix <- purrr::map(sf_list, ~ length(.x)) %>% which.max()
# Next, grab the names of that list element
layer_names <- names(sf_list[[max_ix]])
names(layer_names) <- layer_names
# Now, iterate over the layer names, then the lists, keeping what you need
# and combining
master_list <- purrr::map(layer_names, function(name) {
# print(name) # Leave here for de-bugging
layer_list <- purrr::map(sf_list, ~ {
if (name %in% names(.x)) {
layer <- .x[[name]]
# If layer comes through as mixed geometry, we need to parse it into
# multiple list elements and return that
if (sf::st_geometry_type(layer, by_geometry = FALSE) == "GEOMETRY") {
sub_geoms <- list()
mixed_geoms <- sf::st_geometry_type(layer, by_geometry = TRUE)
if ("POINT" %in% mixed_geoms || "MULTIPOINT" %in% mixed_geoms) {
point_ix <- mixed_geoms %in% c("POINT", "MULTIPOINT")
sub_geoms$points <- layer[point_ix, ] %>%
suppressWarnings(sf::st_cast("MULTIPOINT"))
}
if ("LINESTRING" %in% mixed_geoms || "MULTILINESTRING" %in% mixed_geoms) {
line_ix <- mixed_geoms %in% c("LINESTRING", "MULTILINESTRING")
sub_geoms$lines <- layer[line_ix, ] %>%
sf::st_cast("MULTILINESTRING")
}
if ("POLYGON" %in% mixed_geoms || "MULTIPOLYGON" %in% mixed_geoms) {
polygon_ix <- mixed_geoms %in% c("POLYGON", "MULTIPOLYGON")
sub_geoms$polygons <- layer[polygon_ix, ] %>%
sf::st_cast("MULTIPOLYGON")
}
return(sub_geoms)
} else {
if ("POLYGON" %in% sf::st_geometry_type(layer)) {
# Remove malformed polygons
layer$layer_area <- sf::st_area(layer) %>% as.numeric()
layer <- dplyr::filter(layer, layer_area > 0)
layer <- sf::st_cast(layer, "MULTIPOLYGON")
layer <- dplyr::select(layer, -layer_area)
} else if ("LINESTRING" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTILINESTRING")
} else if ("POINT" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTIPOINT")
}
return(layer)
}
}
}) %>%
purrr::compact()
})
# Within the master list, we need to separate out by geometry type
# We'll have a mix of points, lines, and polygons for some
parsed_list <- purrr::map(layer_names, function(name) {
# ID the specific segment by layer name then smooth out any mixed geoms
segment <- master_list[[name]] %>%
rlang::flatten_if(predicate = function(x) inherits(x, "list"))
# identify how many geometries are in the list
geoms <- purrr::map_int(segment, ~ {
sf::st_geometry_type(.x, by_geometry = FALSE)
})
# If there is only one geometry, return the combined segment across the
# tiles
# Otherwise, we should give back points, lines, and polygons objects as
# appropriate
if (length(unique(geoms)) == 1) {
return(dplyr::bind_rows(segment))
} else if (length(unique(geoms)) > 1) {
output <- list()
if (2L %in% geoms || 1L %in% geoms || 5L %in% geoms) {
point_ix <- geoms %in% c(1L, 2L, 5L)
output$points <- segment[point_ix] %>%
dplyr::bind_rows() %>%
sf::st_cast("MULTIPOINT")
}
if (6L %in% geoms) {
line_ix <- geoms == 6L
output$lines <- segment[line_ix] %>% dplyr::bind_rows()
}
if (7L %in% geoms) {
polygon_ix <- geoms == 7L
output$polygons <- segment[polygon_ix] %>% dplyr::bind_rows()
}
return(output)
}
})
return(parsed_list)
}
# If location is a length-2 numeric vector of longitude/latitude, get the
# specific tile IDs
# If location is an address/text description, geocode it
if (is.vector(location)) {
if (inherits(location, "numeric")) {
if (length(location) != 2) {
stop("Location must be a length-2 vector of format c(lon, lat) if
supplying coordinates as input.")
}
} else if (inherits(location, "character")) {
location <- mb_geocode(location)
}
tile_id <-
slippymath::lonlat_to_tilenum(
location[1], location[2], zoom = zoom
)
# Build the request to Mapbox
url <- sprintf(
"https://api.mapbox.com/v4/%s/%s/%s/%s.mvt",
tileset_id, zoom, tile_id$x, tile_id$y
)
request <- httr::GET(url, query = list(access_token = access_token))
if (request$status_code != 200) {
content <- httr::content(request, as = "text")
stop(print(content$message), call. = FALSE)
}
sf_list <- protolite::read_mvt_sf(request$url)
# Iterate through the elements and parse into sub-elements when geometry is
# mixed
layer_names <- names(sf_list)
names(layer_names) <- layer_names
output_list <- purrr::map(layer_names, function(name) {
layer <- sf_list[[name]]
if (sf::st_geometry_type(layer, by_geometry = FALSE) == "GEOMETRY") {
sub_geoms <- list()
mixed_geoms <- sf::st_geometry_type(layer, by_geometry = TRUE)
if ("POINT" %in% mixed_geoms || "MULTIPOINT" %in% mixed_geoms) {
point_ix <- mixed_geoms %in% c("POINT", "MULTIPOINT")
sub_geoms$points <- layer[point_ix, ] %>%
suppressWarnings(sf::st_cast("MULTIPOINT"))
}
if ("LINESTRING" %in% mixed_geoms || "MULTILINESTRING" %in% mixed_geoms) {
line_ix <- mixed_geoms %in% c("LINESTRING", "MULTILINESTRING")
sub_geoms$lines <- layer[line_ix, ] %>%
sf::st_cast("MULTILINESTRING")
}
if ("POLYGON" %in% mixed_geoms || "MULTIPOLYGON" %in% mixed_geoms) {
polygon_ix <- mixed_geoms %in% c("POLYGON", "MULTIPOLYGON")
sub_geoms$polygons <- layer[polygon_ix, ] %>%
sf::st_cast("MULTIPOLYGON")
}
return(sub_geoms)
} else {
if ("POLYGON" %in% sf::st_geometry_type(layer)) {
# Remove malformed polygons
layer$layer_area <- sf::st_area(layer) %>% as.numeric()
layer <- dplyr::filter(layer, layer_area > 0)
layer <- sf::st_cast(layer, "MULTIPOLYGON")
layer <- dplyr::select(layer, -layer_area)
} else if ("LINESTRING" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTILINESTRING")
} else if ("POINT" %in% sf::st_geometry_type(layer)) {
layer <- sf::st_cast(layer, "MULTIPOINT")
}
return(layer)
}
})
return(output_list)
}
}
#' Return a static Mapbox map from a specified style
#'
#' This function uses the [Mapbox Static Maps
#' API](https://www.mapbox.com/static-maps) to return a pointer to an
#' `"magick-image"` class image or a [httr::response] object from the static map
#' image URL.
#'
#' @inheritParams get_static_tiles
#' @param buffer_dist The distance to buffer around an input `sf` object for
#' determining static map, specified in units. If location is a POINT object
#' of 2 rows or less and `buffer_dist` is 0 or `NULL`, a 1 unit buffer is
#' applied to try to ensure the creation of a valid bounding box for the map
#' area.
#' @param units Units of `buffer_dist`; defaults to "m" (meters). If buffer_dist
#' is a units class object, the units argument is ignored.
#' @param style_id A style ID (required if style_url is `NULL`).
#' @param username A Mapbox username (required if `style_url = NULL`).
#' @param style_url A Mapbox style url; defaults to `NULL`.
#' @param overlay_sf The overlay `sf` object (optional). The function will
#' convert the `sf` object to GeoJSON then plot over the basemap style.
#' Spatial data that are too large will trigger an error, and should be added
#' to the style in Mapbox Studio instead.
#' @param overlay_style A named list of vectors specifying how to style the sf
#' overlay. Possible names are "stroke", "stroke-width" (or "stroke_width"),
#' "stroke-opacity" (or "stroke_opacity"), "fill", and "fill-opacity" (or
#' "fill_opacity"). The fill and stroke color values can be specified as
#' six-digit hex codes or color names, and the opacity and width values should
#' be supplied as floating-point numbers. If overlay_style is `NULL`, the
#' style values can be pulled from columns with the same names in
#' `overlay_sf`.
#' @param overlay_markers The prepared overlay markers (optional). See the
#' function [prep_overlay_markers] for more information on how to specify a
#' marker overlay.
#' @param longitude,latitude The longitude and latitude of the map center. If an
#' overlay is supplied, the map will default to the extent of the overlay
#' unless longitude, latitude, and zoom are all specified.
#' @param zoom The map zoom. The map will infer this from the overlay unless
#' longitude, latitude, and zoom are all specified.
#' @param width,height The map width and height; defaults to `NULL`
#' @param pitch,bearing The map pitch and bearing; defaults to `NULL`. pitch can
#' range from 0 to 60, and bearing from -360 to 360.
#' @param scale ratio to scale the output image; `scale = 1` will return the
#' largest possible image. defaults to 0.5
#' @param scaling_factor The scaling factor of the tiles; either `"1x"`
#' (the default) or `"2x"`
#' @param attribution Controls whether there is attribution on the image.
#' Defaults to `TRUE`. If `FALSE`, the watermarked attribution is removed from
#' the image. You still have a legal responsibility to attribute maps that use
#' OpenStreetMap data, which includes most maps from Mapbox. If you specify
#' `attribution = FALSE`, you are legally required to include proper
#' attribution elsewhere on the webpage or document.
#' @param logo Controls whether there is a Mapbox logo on the image. Defaults to
#' `TRUE`.
#' @param before_layer A character string that specifies where in the hierarchy
#' of layer elements the overlay should be inserted. The overlay will be
#' placed just above the specified layer in the given Mapbox styles. List
#' layer ids for a map style with `get_style(style_id = style_id, username =
#' username, style_url = style_url, access_token =
#' access_token)[["layers"]][["id"]]`
#' @param access_token A Mapbox access token; which can be set with
#' [mb_access_token].
#' @param image If `FALSE`, return the a [httr::response] object from
#' [httr::GET] using the static image URL; defaults to `TRUE`.
#' @param strip If `TRUE`, drop image comments and metadata when `image = TRUE`;
#' defaults to `TRUE`.
#' @return A pointer to an image of class `"magick-image"` if `image = TRUE`.
#' The resulting image can be manipulated further with functions from the
#' magick package.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#'
#' points_of_interest <- tibble::tibble(
#' longitude = c(-73.99405, -74.00616, -73.99577, -74.00761),
#' latitude = c(40.72033, 40.72182, 40.71590, 40.71428)
#' )
#'
#' prepped_pois <- prep_overlay_markers(
#' data = points_of_interest,
#' marker_type = "pin-l",
#' label = 1:4,
#' color = "fff"
#' )
#'
#' map <- static_mapbox(
#' style_id = "streets-v11",
#' username = "mapbox",
#' overlay_markers = prepped_pois,
#' width = 1200,
#' height = 800
#' )
#'
#' map
#' }
#'
#' @export
#' @importFrom httr GET content
#' @importFrom jsonlite fromJSON
#' @importFrom magick image_read
static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
longitude = NULL,
latitude = NULL,
zoom = NULL,
width = NULL,
height = NULL,
bearing = NULL,
pitch = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
image = TRUE,
strip = TRUE) {
access_token <- get_mb_access_token(access_token)
base <-
set_static_map_style(
style_url = style_url,
username = username,
style_id = style_id
)
# Next, figure out the overlay
# Basically, the idea is that you can string together GeoJSON, markers, etc.
# on a map and put it over a Mapbox style. overlay should accept such
# components and format them accordingly.
#
# `overlay_sf` converts to GeoJSON to make the request.
# The input GeoJSON should have internal information conforming to
# simplestyle-spec Eventually, this function could be able to do that
# internally but not yet
base <-
set_static_map_overlay(
base = base,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers
)
merc_bbox <- location_to_bbox(location, buffer_dist, units, crs = 3857)
lonlat_bbox <- location_to_bbox(location, buffer_dist, units, crs = 4326)
focus_args <- c(longitude, latitude, zoom)
if (all(is.null(focus_args))) {
if (is.null(location)) {
focus <- "auto"
} else {
focus <- paste0("[", paste0(lonlat_bbox, collapse = ","), "]")
}
} else {
if (!is.null(location) && all(sapply(c(longitude, latitude), is.null))) {
center <- bbox_to_center(lonlat_bbox, crs = 4326)
longitude <- center[1]
latitude <- center[2]
}
if (is.null(zoom)) {
zoom <- 11
}
stopifnot(
"`zoom` must be between 0 and 22" = (zoom >= 0) && (zoom <= 22)
)
focus_args <- c(longitude, latitude, zoom)
stopifnot(
all(!is.null(focus_args))
)
if (is.null(bearing)) {
bearing <- 0
} else if ((bearing < 0) && (bearing >= -360)) {
bearing <- 360 + bearing
}
if (is.null(pitch)) {
pitch <- 0
}
stopifnot(
"`bearing` must be between -360 and 360" = ((bearing >= 0) && (bearing <= 360)),
"`pitch` must be between 0 and 60" = ((pitch >= 0) && (pitch <= 60))
)
focus_args <- c(focus_args, bearing, pitch)
focus <- paste0(focus_args, collapse = ",")
}
base <- paste(base, focus, sep = "/")
base1 <-
set_static_map_dims(
base = base,
bbox = merc_bbox,
width = width,
height = height,
scale = scale
)
scaling_factor <- match.arg(scaling_factor)
if (scaling_factor == "2x") {
base1 <- sprintf("%s@2x", base1)
}
if (nchar(base1) > 8192) {
stop("Your request is too large likely due to the size of your overlay
geometry. Consider simplifying your overlay geometry or adding your
data to a style in Mapbox Studio to resolve this.", call. = FALSE)
}
if (!is.null(before_layer)) {
before_layer <-
match.arg(
before_layer,
get_style(
style_id = style_id,
username = username,
style_url = style_url,
access_token = access_token
)[["layers"]][["id"]]
)
}
request <-
httr::GET(
base1,
query = list(
access_token = access_token,
attribution = tolower(attribution),
logo = tolower(logo),
before_layer = before_layer
)
)
if (request$status_code != 200) {
content <- httr::content(request, as = "text")
stop(print(jsonlite::fromJSON(content)), call. = FALSE)
}
if (!image) {
return(request)
}
if (!rlang::is_installed("magick") && rlang::is_interactive()) {
rlang::check_installed("magick")
}
magick::image_read(httr::content(request), strip = strip)
}
#' Add username and style_id to API query for static_mapbox
#'
#' @noRd
#' @importFrom stringi stri_extract
set_static_map_style <- function(style_url = NULL, username, style_id) {
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url,
regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url,
regex = paste0("(?<=", username, "/).+"))
}
# Construct the request URL
# First, do chunk 1
base <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/static",
username, style_id
)
return(base)
}
#' Add overlay to API query for static_mapbox
#'
#' @noRd
#' @importFrom sf st_sf
#' @importFrom utils URLencode
#' @importFrom geojsonsf sf_geojson
set_static_map_overlay <- function(base = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL) {
overlay <- NULL
if (!is.null(overlay_sf)) {
if (is_sfc(overlay_sf)) {
overlay_sf <- sf::st_sf(overlay_sf)
}
overlay_sf <-
set_overlay_style(
overlay_sf = overlay_sf,
overlay_style = overlay_style
)
if (sf::st_crs(overlay_sf)["input"] != "EPSG:4326") {
overlay_sf <- sf::st_transform(overlay_sf, 4326)
}
overlay_json <- geojsonsf::sf_geojson(overlay_sf)
overlay <- sprintf("geojson(%s)", overlay_json)
}
if (!is.null(overlay_markers)) {
if (attr(overlay_markers, "mapboxapi") != "marker_spec") {
stop("Overlay markers should be formatted with `prep_overlay_markers()`
before using in a static map", call. = FALSE)
}
marker_spec <- overlay_markers %>%
unlist() %>%
paste0(collapse = ",")
if (!is.null(overlay)) {
overlay <- paste(overlay, marker_spec, sep = ",")
} else {
overlay <- marker_spec
}
}
if (!is.null(overlay)) {
return(paste(base, overlay, sep = "/"))
}
base
}
#' Set overlay style
#'
#' @noRd
#' @importFrom utils URLencode
set_overlay_style <-
function(overlay_sf,
overlay_style = NULL) {
if (is.null(overlay_style)) {
overlay_style <- overlay_sf[1, ]
}
style_names <- names(overlay_style)
if ("stroke" %in% style_names) {
if (!is_hex(overlay_style$stroke)) {
overlay_style$stroke <- col2hex(overlay_style$stroke)
}
overlay_sf$stroke <-
utils::URLencode(overlay_style$stroke, reserved = TRUE)
}
if ("stroke-opacity" %in% style_names) {
overlay_sf$`stroke-opacity` <-
utils::URLencode(
as.character(overlay_style$`stroke-opacity`),
reserved = TRUE
)
}
if ("stroke_opacity" %in% style_names) {
overlay_sf$`stroke-opacity` <-
utils::URLencode(
as.character(overlay_style$stroke_opacity),
reserved = TRUE
)
}
if ("stroke-width" %in% style_names) {
overlay_sf$`stroke-width` <-
utils::URLencode(
as.character(overlay_style$`stroke-width`),
reserved = TRUE
)
}
if ("stroke_width" %in% style_names) {
overlay_sf$`stroke-width` <-
utils::URLencode(
as.character(overlay_style$stroke_width),
reserved = TRUE
)
}
if ("fill" %in% style_names) {
if (!is_hex(overlay_style$fill)) {
overlay_style$fill <- col2hex(overlay_style$fill)
}
overlay_sf$fill <-
utils::URLencode(overlay_style$fill, reserved = TRUE)
}
if ("fill_opacity" %in% style_names) {
overlay_sf$`fill-opacity` <-
utils::URLencode(
as.character(overlay_style$fill_opacity),
reserved = TRUE
)
}
if ("fill-opacity" %in% style_names) {
overlay_sf$`fill-opacity` <-
utils::URLencode(
as.character(overlay_style$`fill-opacity`),
reserved = TRUE
)
}
overlay_sf
}
#' Add width/height to API query for static_mapbox
#'
#' @noRd
set_static_map_dims <- function(base = NULL,
bbox = NULL,
width = NULL,
height = NULL,
scale = 0.5) {
has_map_dims <- !all(is.null(c(width, height)))
if (!has_map_dims && !is.null(bbox)) {
asp <- as.numeric(abs(bbox$xmax - bbox$xmin) / abs(bbox$ymax - bbox$ymin))
max_size <- min(1280, round(1280 * scale))
width <- min(max_size, round(max_size * asp))
height <- min(max_size, round(max_size / asp))
} else if (has_map_dims) {
width <- round(width)
height <- round(height)
}
sprintf("%s/%sx%s", base, width, height)
}
#' Make a static Mapbox ggplot2 layer or tmap basemap
#'
#' These functions wrap [static_mapbox()] and [ggspatial::layer_spatial()] or
#' [tmap::tm_rgb()] to support the use of images from the [Mapbox Static Maps
#' API](https://www.mapbox.com/static-maps) as
#' [{ggplot2}](https://ggplot2.tidyverse.org/) or
#' [{tmap}](https://r-tmap.github.io/tmap/) basemaps.
#'
#' This function uses a different approach than [get_static_tiles()]. Instead,
#' [layer_static_mapbox()] is based largely on `layer_mapbox()` in the snapbox package
#' (available under a [MIT
#' license](https://github.com/anthonynorth/snapbox/blob/master/LICENSE). There
#' are a few key differences between [layer_static_mapbox()] and
#' `layer_mapbox()`. The "scale" parameter is equivalent to the
#' "scale_ratio" parameter for snapbox. Setting `scale_factor = "2x"` is
#' equivalent to setting `retina = TRUE.` Both functions return basemaps that
#' are no larger than a single tile (a maximum of 1280 by 1280 pixels).
#'
#' For [tm_static_mapbox()], [tmap::tm_shape] is called with `projection = 3857` and
#' [tmap::tm_rgb] is called with `max.value = 1`.
#'
#' @rdname layer_static_mapbox
#' @inheritParams static_mapbox
#' @param ... additional parameters passed to [ggspatial::layer_spatial] or [tmap::tm_rgb]
#' @export
#' @author Eli Pousson, \email{eli.pousson@gmail.com}
#' @author Anthony North, \email{anthony.jl.north@gmail.com}
#' @author Miles McBain, \email{miles.mcbain@gmail.com}
#' @importFrom rlang is_installed is_interactive check_installed
layer_static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
width = NULL,
height = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
...) {
if (!rlang::is_installed("ggspatial") && rlang::is_interactive()) {
rlang::check_installed("ggspatial")
}
request <-
static_mapbox(
location = location,
buffer_dist = buffer_dist,
units = units,
style_id = style_id,
username = username,
style_url = style_url,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers,
width = width,
height = height,
scale = scale,
scaling_factor = scaling_factor,
attribution = attribution,
logo = logo,
before_layer = before_layer,
access_token = access_token,
image = FALSE
)
ras <- request_to_raster(request, location, buffer_dist, units)
ggspatial::layer_spatial(data = ras, ...)
}
#' @name tm_static_mapbox
#' @rdname layer_static_mapbox
#' @inheritParams static_mapbox
#' @importFrom rlang is_installed is_interactive check_installed
#' @export
tm_static_mapbox <- function(location = NULL,
buffer_dist = 1000,
units = "m",
style_id,
username,
style_url = NULL,
overlay_sf = NULL,
overlay_style = NULL,
overlay_markers = NULL,
width = NULL,
height = NULL,
scale = 0.5,
scaling_factor = c("1x", "2x"),
attribution = TRUE,
logo = TRUE,
before_layer = NULL,
access_token = NULL,
...) {
if (!rlang::is_installed("tmap") && rlang::is_interactive()) {
rlang::check_installed("tmap")
}
request <-
static_mapbox(
location = location,
buffer_dist = buffer_dist,
units = units,
style_id = style_id,
username = username,
style_url = style_url,
overlay_sf = overlay_sf,
overlay_style = overlay_style,
overlay_markers = overlay_markers,
width = width,
height = height,
scale = scale,
scaling_factor = scaling_factor,
attribution = attribution,
logo = logo,
before_layer = before_layer,
access_token = access_token,
image = FALSE
)
ras <- request_to_raster(request, location, buffer_dist, units)
tmap::tm_shape(shp = ras, projection = 3857) +
tmap::tm_rgb(max.value = 1, ...)
}
#' Convert static_mapbox API request to raster image
#'
#' @noRd
#' @importFrom sf st_crs
#' @importFrom raster brick extent projection
#' @importFrom httr content
request_to_raster <- function(request,
location = NULL,
buffer_dist = NULL,
units = "m") {
ras <- raster::brick(httr::content(request))
merc_bbox <- location_to_bbox(location, buffer_dist, units, crs = 3857)
merc_proj <- sf::st_crs(3857)$proj4string
raster::extent(ras) <- merc_bbox
suppressWarnings(raster::projection(ras) <- merc_proj)
ras
}
#' Prepare overlay markers for use in a Mapbox static map
#'
#' Markers are prepared to match GeoJSON
#' [marker-spec](https://github.com/mapbox/mapbox-gl-markers#geojson-marker-spec)
#' which is a partial implementation of the GeoJSON
#' [simplestyle-spec](https://github.com/mapbox/simplestyle-spec/tree/master/1.1.0)
#' (described as a work-in-progress by Mapbox).
#'
#' @param data An input data frame with longitude and latitude columns (X and Y
#' or lon and lat as names are also acceptable) or an `sf` object with
#' geometry type POINT.
#' @param marker_type The marker type; one of `"pin-s"`, for a small pin;
#' `"pin-l"`, for a large pin; and `"url"`, for an image path. If
#' marker_type is the same length as the rows in data, a mix of different
#' marker types are allowed.
#' @param label The marker label (optional). Can be a letter, number (0 through
#' 99), or a valid Maki icon (see <https://labs.mapbox.com/maki-icons/>)
#' for options).
#' @param color The marker color (optional). `color` can be specified as a color
#' name or as a three or six-digit hexadecimal code (with or without the
#' number sign).
#' @param longitude A vector of longitudes; inferred from the input dataset if
#' `data` is provided.
#' @param latitude A vector of latitudes; inferred from the input dataset if
#' `data` is provided.
#' @param url The URL of the image to be used for the icon if `marker_type =
#' "url"`.
#' @name prep_overlay_markers
#' @return A formatted list of marker specifications that can be passed to the
#' [static_mapbox] function.
#' @export
#' @importFrom sf st_geometry_type st_point_on_surface st_transform
#' st_coordinates
#' @importFrom purrr map
prep_overlay_markers <- function(data = NULL,
marker_type = c("pin-s", "pin-l", "url"),
label = NA,
color = NA,
longitude = NULL,
latitude = NULL,
url = NA) {
if (!is.null(data)) {
if (any(grepl("^sf", class(data)))) {
if (sf::st_geometry_type(data, by_geometry = FALSE) != "POINT") {
data <- suppressWarnings(sf::st_point_on_surface(data))
}
# Construct the marker data frame
coords_df <- data %>%
sf::st_transform(4326) %>%
sf::st_coordinates() %>%
as.data.frame()
coords_df <- cbind(data, coords_df)
} else {
coords_df <- data
}
# Infer coordinates from column names
names(coords_df) <- tolower(names(coords_df))
if (all(c("lon", "lat") %in% names(coords_df))) {
coords_df$longitude <- coords_df$lon
coords_df$latitude <- coords_df$lat
} else if (all(c("x", "y") %in% names(coords_df))) {
coords_df$longitude <- coords_df$x
coords_df$latitude <- coords_df$y
}
if (!all(c("longitude", "latitude") %in% names(coords_df))) {
stop("Your input dataset must have longitude/latitude information denoted
by columns x and y, lon and lat, or longitude and latitude.",
call. = FALSE
)
}
if ("marker_type" %in% names(coords_df)) {
marker_type <- coords_df$marker_type
} else {
marker_type <-
match.arg(
marker_type, c("pin-s", "pin-l", "url"),
several.ok = length(marker_type) == nrow(coords_df)
)
coords_df$marker_type <- marker_type
}
if ("label" %in% names(coords_df)) {
label <- coords_df$label
} else {
if (!is.null(label)) {
coords_df$label <- label
}
}
if ("color" %in% names(coords_df)) {
color <- coords_df$color
} else {
if (!is.null(color)) {
coords_df$color <- color
}
}
if (!all(is.null(coords_df$color))) {
if (!is_hex(coords_df$color)) {
coords_df$color <- col2hex(coords_df$color, TRUE)
} else {
coords_df$color <- rmv_hash(coords_df$color)
}
}
if ("url" %in% names(coords_df)) {
url <- coords_df$url
} else {
if (!is.null(url)) {
coords_df$url <- url
}
}
} else {
if (!is.null(color)) {
if (!is_hex(color)) {
color <- col2hex(color, TRUE)
} else {
color <- rmv_hash(color)
}
}
coords_df <-
data.frame(
longitude = longitude,
latitude = latitude,
marker_type = marker_type,
label = label,
color = color,
url = url
)
}
# Iterate through the coords_df to make a formatted list of markers
marker_list <- purrr::map(1:nrow(coords_df), ~ {
format_marker(.x, coords_df = coords_df, url = url)
})
attr(marker_list, "mapboxapi") <- "marker_spec"
marker_list
}
#' Format marker using marker_spec based on n row of a coordinate data frame
#'
#' @noRd
#' @importFrom utils URLencode
format_marker <- function(n, coords_df = NULL, url = NULL) {
r <- coords_df[n, ]
if (r$marker_type %in% c("pin-s", "pin-l")) {
if (!is.na(r$label) && !is.na(r$color)) {
return(sprintf(
"%s-%s+%s(%s,%s)",
r$marker_type,
tolower(r$label),
r$color,
r$longitude,
r$latitude
))
} else if (is.na(r$label) && !is.na(r$color)) {
return(sprintf(
"%s-%s(%s,%s)",
r$marker_type,
r$color,
r$longitude,
r$latitude
))
} else if (!is.na(r$label) && is.na(r$color)) {
return(sprintf(
"%s-%s(%s,%s)",
r$marker_type,
tolower(r$label),
r$longitude,
r$latitude
))
} else {
return(sprintf(
"%s-(%s,%s)",
r$marker_type,
r$longitude,
r$latitude
))
}
} else if (r$marker_type == "url") {
if (is.null(url)) {
stop("A valid URL must be provided.")
}
encoded_url <- utils::URLencode(r$url, reserved = TRUE)
return(sprintf(
"url-%s(%s,%s)",
encoded_url,
r$longitude,
r$latitude
))
}
}
#' Use a Mapbox style in a Leaflet map
#'
#' See the [Mapbox Static Tiles API
#' documentation](https://docs.mapbox.com/api/maps/static-tiles/) for more
#' information.
#'
#' @param map A map widget object created by [leaflet::leaflet()]
#' @param style_url A Mapbox style URL
#' @param style_id The style ID of a Mapbox style
#' @param username A Mapbox username
#' @param scaling_factor The scaling factor to use when rendering the tiles. A
#' scaling factor of `"1x"` (the default) returns 512px by 512px tiles. A
#' factor of `"1x"` returns 256x256 tiles, and a factor of `"2x"` returns
#' 1024x1024 tiles.
#' @param access_token Your Mapbox access token; which can be set with
#' [mb_access_token()].
#' @param layerId the layer ID
#' @param group The name of the group the Mapbox tile layer should belong to
#' (for use in Shiny and to modify layers control in a Leaflet workflow)
#' @param options A list of extra options (optional)
#' @param data The data object used to derive argument values; can be provided
#' to the initial call to [leaflet::leaflet()]
#' @param attribution If `TRUE`, pass a standard attribution to
#' [leaflet::addTiles()]. If `FALSE`, attribution is `NULL`. attribution can
#' also be a character string including HTML.
#' @return A pointer to the Mapbox Static Tiles API which will be translated
#' appropriately by the leaflet R package.
#'
#' @examples \dontrun{
#'
#' library(leaflet)
#' library(mapboxapi)
#'
#' leaflet() %>%
#' addMapboxTiles(
#' style_id = "light-v9",
#' username = "mapbox"
#' ) %>%
#' setView(
#' lng = -74.0051,
#' lat = 40.7251,
#' zoom = 13
#' )
#' }
#'
#' @export
addMapboxTiles <- function(map,
style_id,
username,
style_url = NULL,
scaling_factor = c("1x", "0.5x", "2x"),
access_token = NULL,
layerId = NULL,
group = NULL,
options = leaflet::tileOptions(),
data = leaflet::getMapData(map),
attribution = TRUE) {
access_token <- get_mb_access_token(access_token)
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url, regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url, regex = paste0("(?<=", username, "/).+"))
}
sfactor <- match.arg(scaling_factor)
url <-
switch(sfactor,
"1x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/{z}/{x}/{y}?access_token=%s", username, style_id, access_token),
"0.5x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/256/{z}/{x}/{y}?access_token=%s", username, style_id, access_token),
"2x" = sprintf("https://api.mapbox.com/styles/v1/%s/%s/tiles/{z}/{x}/{y}@2x?access_token=%s", username, style_id, access_token)
)
if (!is.character(attribution)) {
if (attribution) {
attribution <- '© <a href="https://www.mapbox.com/about/maps/">Mapbox</a> © <a href="http://www.openstreetmap.org/copyright">OpenStreetMap</a> <strong><a href="https://www.mapbox.com/map-feedback/" target="_blank">Improve this map</a></strong>'
} else {
attribution <- NULL
}
}
leaflet::addTiles(
map = map,
urlTemplate = url,
attribution = attribution,
layerId = layerId,
group = group,
options = options,
data = data
)
}
#' Get static tiles from a Mapbox style for use as a basemap
#'
#' This function queries the [Mapbox Static Tiles
#' API](https://docs.mapbox.com/api/maps/static-tiles/) and composites the tiles
#' as a raster suitable for use as a basemap in
#' [tmap](https://r-tmap.github.io/tmap/) or
#' [ggplot2](https://ggplot2.tidyverse.org/) (with the
#' [ggspatial::layer_spatial()] function. It returns a raster
#' layer that corresponds either to an input bounding box or a buffered area
#' around an input shape.
#'
#' @param location An input location for which you would like to request tiles.
#' Can be a length-4 vector representing a bounding box, or an `sf` object.
#' If an input `sf` object is supplied, use the `buffer_dist` argument to
#' control how much area you want to capture around the layer.
#' While the input `sf` object can be in an arbitrary coordinate reference system,
#' if a length-4 bounding box vector is supplied instead it must represent
#' WGS84 longitude/latitude coordinates and be in the order
#' `c(xmin, ymin, xmax, ymax)`.
#' @param zoom The zoom level for which you'd like to return tiles.
#' @param style_id A Mapbox style ID; retrieve yours from your Mapbox account.
#' @param username A Mapbox username.
#' @param style_url A Mapbox style URL.
#' @param scaling_factor The scaling factor to use; one of `"1x"` or `"2x"`.
#' @param buffer_dist The distance to buffer around an input `sf` object for determining tile extent, specified in units. Defaults to 5000.
#' @param units Units of `buffer_dist`; defaults to "m" (meters). If buffer_dist
#' is a units class object, the units argument is ignored.
#' @param crop Whether or not to crop the result to the specified bounding box or buffer area.
#' Defaults to `TRUE`; `FALSE` will return the extent of the overlapping
#' tiles.
#' @param access_token A Mapbox access token. Supply yours here or set globally with the [mb_access_token()] function.
#'
#' @return A raster layer of tiles from the requested Mapbox style representing the area around the input location. The raster layer is projected in the Web Mercator coordinate reference system.
#'
#' @examples \dontrun{
#'
#' library(mapboxapi)
#' library(tigris)
#' library(tmap)
#' library(ggspatial)
#' library(ggplot2)
#'
#' ny_tracts <- tracts("NY", "New York", cb = TRUE)
#'
#' ny_tiles <- get_static_tiles(
#' location = ny_tracts,
#' zoom = 10,
#' style_id = "light-v9",
#' username = "mapbox"
#' )
#'
#' # tmap usage:
#' tm_shape(ny_tiles) +
#' tm_rgb() +
#' tm_shape(ny_tracts) +
#' tm_polygons(alpha = 0.5, col = "navy") +
#' tm_credits("Basemap (c) Mapbox, (c) OpenStreetMap",
#' position = c("RIGHT", "BOTTOM")
#' )
#'
#' # ggplot2 usage:
#' ggplot() +
#' layer_spatial(ny_tiles) +
#' geom_sf(data = ny_tracts, fill = "navy", alpha = 0.5) +
#' theme_void() +
#' labs(caption = "Basemap (c) Mapbox, (c) OpenStreetMap")
#' }
#'
#' @export
get_static_tiles <- function(location,
zoom,
style_id,
username,
style_url = NULL,
scaling_factor = c("1x", "2x"),
buffer_dist = 5000,
units = "m",
crop = TRUE,
access_token = NULL) {
message("Attribution is required if using Mapbox tiles on a map.\nAdd the text '(c) Mapbox, (c) OpenStreetMap' to your map for proper attribution.")
access_token <- get_mb_access_token(access_token)
if (!is.null(style_url)) {
username <- stringi::stri_extract(style_url, regex = paste0("(?<=styles/).+(?=/)"))
style_id <- stringi::stri_extract(style_url, regex = paste0("(?<=", username, "/).+"))
}
bbox <- location_to_bbox(location, buffer_dist, units)
tile_grid <- slippymath::bbox_to_tile_grid(bbox = bbox, zoom = zoom)
tile_ids <- tile_grid$tiles
sfactor <- match.arg(scaling_factor)
tile_list <- purrr::map2(tile_ids$x, tile_ids$y, ~ {
# Build the request to Mapbox
if (sfactor == "2x") {
url <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/tiles/%s/%s/%s@2x",
username, style_id, zoom, .x, .y
)
} else {
url <- sprintf(
"https://api.mapbox.com/styles/v1/%s/%s/tiles/%s/%s/%s",
username, style_id, zoom, .x, .y
)
}
box <- slippymath::tile_bbox(.x, .y, zoom)
tmp <- tempdir()
loc <- file.path(tmp, sprintf("%s_%s.png", .x, .y))
request <- httr::GET(url,
query = list(access_token = access_token),
httr::write_disk(loc, overwrite = TRUE)
)
# Only try to read the data if there is data available
if (request$status_code == 200) {
# Most styles will be returned as PNG as they are composed entirely
# of vector layers. However, if a style includes satellite imagery it will
# be returned as JPEG. Check this at this step.
my_img <- try(png::readPNG(loc), silent = TRUE)
if ("try-error" %in% class(my_img)) {
my_img <- jpeg::readJPEG(loc)
}
my_img <- my_img * 255
merc <- sf::st_crs(3857)$proj4string
ras <- raster::brick(my_img)
raster::extent(ras) <- box
suppressWarnings(raster::projection(ras) <- merc)
return(ras)
}
})
# Assemble the list of raster tiles
# Adapted from Michael Sumner's ceramic code: https://github.com/hypertidy/ceramic/blob/master/R/raster.R
if (length(tile_list) == 1) {
out_brick <- tile_list[[1]]
} else {
target_crs <- suppressWarnings(raster::projection(tile_list[[1]]))
out_raster <- suppressWarnings(tile_list %>%
purrr::map(function(tile) {
raster::extent(tile)
}) %>%
purrr::reduce(raster::union) %>%
raster::raster(crs = target_crs))
raster::res(out_raster) <- suppressWarnings(raster::res(tile_list[[1]]))
raster_cells <- suppressWarnings(tile_list %>%
map(function(tile) {
raster::cellsFromExtent(out_raster, tile)
}) %>%
unlist(use.names = FALSE))
raster_values <- suppressWarnings(tile_list %>%
map(function(tile) {
raster::values(tile)
}) %>%
reduce(rbind))
out_brick <- suppressWarnings(raster::brick(out_raster, out_raster, out_raster) %>%
raster::setValues(raster_values[order(raster_cells), ]))
}
if (crop) {
bb_shape <- bbox %>%
sf::st_as_sfc(crs = 4326) %>%
sf::st_sf() %>%
sf::st_transform(sf::st_crs(out_brick))
cropped_brick <- raster::crop(out_brick, bb_shape)
return(cropped_brick)
} else {
return(out_brick)
}
}
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