Layer location data into a ggplot2 map

Helper function to make a ggplot2 layer from data returned by get_location_data(). For text geoms, the required aesthetic mapping is set based on the name_col but values passed to mapping take precedence.

Usage

layer_location_data(
  mapping = NULL,
  data = NULL,
  geom = "sf",
  location = NULL,
  dist = getOption("maplayer.dist"),
  diag_ratio = getOption("maplayer.diag_ratio"),
  unit = getOption("maplayer.unit", default = "meter"),
  asp = getOption("maplayer.asp"),
  package = getOption("maplayer.data_package"),
  pkg = getOption("maplayer.data_package"),
  fileext = getOption("maplayer.data_fileext", "gpkg"),
  filetype = NULL,
  fn = NULL,
  layer_fn = NULL,
  crop = TRUE,
  trim = FALSE,
  from_crs = getOption("maplayer.from_crs", 4326),
  crs = getOption("maplayer.crs", 3857),
  label_col = "name",
  smooth_params = NULL,
  shadow_params = NULL,
  basemap = FALSE,
  ...
)

Arguments

mapping

Set of aesthetic mappings created by aes(). If specified and inherit.aes = TRUE (the default), it is combined with the default mapping at the top level of the plot. You must supply mapping if there is no plot mapping.

data

Character string (e.g. url, file path, or name of data from package) for a spatial data or a sf, sfc, or bbox object with geometry overlapping the location. If data is NULL, all unnamed parameters are passed to sfext::read_sf_ext() with a bbox based on location. If data is not NULL and not a data.frame, url, file path, or bbox, conversion to a sf object will still always be attempted with sfext::as_sf().

geom

A character string indicating which ggplot2 geom to use, Default: 'sf'. Options include "sf" (ggplot2::geom_sf()), "icon" (layer_icon()), "markers" (layer_markers()), "sf_text" (ggplot2::geom_sf_text()), and "sf_label" (ggplot2::geom_sf_label()). See details for a full list.

location

sf object. If multiple areas are provided, they are unioned into a single sf object using sf::st_union()

dist

buffer distance in units. Optional.

diag_ratio

ratio of diagonal distance of area's bounding box used as buffer distance. e.g. if the diagonal distance is 3000 meters and the "diag_ratio = 0.1" a 300 meter will be used. Ignored when dist is provided.

unit

unit to adjust location by dist or diag_ratio; defaults to "meter"

asp

Aspect ratio of width to height as a numeric value (e.g. 0.33) or character (e.g. "1:3"). If numeric, get_asp() returns the same value without modification.

pkg, package

Name of the package to search for data.

fileext, filetype

File extension or type to use if passing parameters to sfext::read_sf_download() or sfext::read_sf_pkg() (required for extdata and cached data).

fn

Function to apply to data after filtering by location but before returning from function.

layer_fn

ggplot2 geom or custom function using lambda syntax. Use for passing custom mapping functions to layer_location_data beyond the supported geom options.

crop

If TRUE, x is cropped to y using sf::st_crop().

trim

If TRUE, x is trimmed to y with st_trim().

from_crs

Coordinate reference system used to match the location CRS to the source data.

crs

Coordinate reference system to return.

label_col

Column name or id for a column with the text or labels to pass to any text geom.

smooth_params

Optional. Logical or a list of parameters passed to smoothr::smooth(). If TRUE, apply smoothr::smooth() to location data using default parameters. smooth_params is ignored if data is NULL (inheriting data from ggplot).

shadow_params

Optional. Logical or a list of parameters passed to ggfx::with_shadow(). If TRUE, apply ggfx::with_shadow() to the layer using default parameters. shadow_params is ignored if layer_fn is provided.

basemap

Either a logical vector or ggplot object.

If logical and TRUE, add x to ggplot2::ggplot(). If FALSE, return x as is.

If a ggplot, add x to basemap object.

If a ggproto object (or list that contains a ggproto object), add x and basemap object to ggplot2::ggplot().

...

Additional parameters passed to selected geom or layer_fn

Using the geom parameter

This function provides a convenient option for filtering data by location while calling a different layer function from ggplot2, maplayer, or a different package.

Options for the geom parameter from ggplot2:

"sf" (ggplot2::geom_sf - default)
"sf_text" or "text (ggplot2::geom_sf_text)
"sf_label" or "label (ggplot2::geom_sf_label)

Options for the geom parameter included in this package include:

"location" (layer_location)
"context" or "location_context" (layer_location_context)
"icon" (layer_icon),
"mapbox" (layer_mapbox)
"markers" (layer_markers)
"numbers" or "numbered" (layer_numbers)
"mark" or "marked" (layer_marked)

Options for the geom parameter from other suggested packages include:

"textsf" (geomtextpath::geom_textsf)
"labelsf" (geomtextpath::geom_labelsf)
"text_repel" (ggrepel::geom_text_repel)
"label_repel" (ggrepel::geom_label_repel)
"sf_pattern" or "pattern" (ggpattern::geom_sf_pattern)

stat = "sf_coordinates" is automatically added to the parameters for both ggrepel functions. label = .data[[name_col]] is automatically added to all provided geoms where label is a required parameter.

Using the layer_fn parameter

layer_fn can be a purrr-style lamba function (converted with rlang::as_function()) or a function.

Usage

Arguments

Using the geom parameter

Using the layer_fn parameter

See also