Package 'maposm'

Package description

Description

The OpenStreetMap database provides a wide range of highly detailed geographic layers on a global scale. To obtain synthetic information for cartographic purposes, layers must be selected, simplified, merged, or modified. maposm downloads OpenStreetMap extracts and performs these operations to create a set of composite layers of urban areas, buildings, green spaces, main roads, secondary roads, railways, and water bodies.

om_get is used to download, merge and simplify the geographic layers.
om_map is used to map the layers. Several themes are available to map the layers ("light", "dark", "grey" and "pizza").
om_write can be used to write the layers to a geopackage file.
om_read can be used to read these geopackages.

Author(s)

Maintainer: Timothée Giraud [email protected] (ORCID)

Authors:

• Timothée Giraud [email protected] (ORCID)

Other contributors:

• Matthieu Viry (ORCID) [contributor]

• Louis Laurian (ORCID) [contributor]

See Also

Useful links:

• https://codeberg.org/riatelab/maposm

• https://riatelab.r-universe.dev/maposm

• Report bugs at https://codeberg.org/riatelab/maposm/issues

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Get map layers

Description

Download various OpenStreetMap features to create map layers.

Usage

om_get(
  x,
  r,
  download_directory = tempdir(),
  force_download = FALSE,
  max_file_size = 20,
  force_building = FALSE,
  quiet = FALSE
)

Arguments

x	an sf or sfc object, or a couple of coordinates (lon/lat, EPSG:4326)
r	radius of the extraction if x is an sf POINT or a couple of coordinates
download_directory	directory to store the file containing raw OpenStreetMap data
force_download	if TRUE, the OpenSteetMap file is updated even if it has already been downloaded.
max_file_size	the maximum file size to download without asking in interactive mode, in megabytes (default to 20 MB)
force_building	force the extraction of buildings in zones larger than 20 km²
quiet	if FALSE, the function prints informative messages

Value

A list of map layers is returned :

• zone, the extraction zone;

• urban, urban areas;

• building, buildings (if the extraction zone area is below 20 km² or force_building = TRUE);

• green, green spaces;

• road, main roads;

• street, secondary roads;

• railway, railways (line);

• water, water bodies

If x uses an unprojected CRS (lon/lat, EPSG:4326), ouput uses Web Mercator CRS (EPSG:3857), it uses x CRS otherwise.

Examples

res = om_get(c(-61.070, 14.605), r = 600)
om_map(res, title = "Fort-de-France town centre")

---

Map layers

Description

Display a map of the downloaded layers.

Usage

om_map(x, title = "Data from OpenStreetMap", theme = "light")

Arguments

x	a list of map layers
title	map title
theme	cartographic theme; "light", "dark", "grey" or "pizza"

Value

Nothing is returned. A map is displayed.

Examples

res = om_get(c(-61.070, 14.605), r = 600)
om_map(res, title = "Fort-de-France town centre", theme = "light")

---

Import a list of map layers

Description

Read and import a list of layers.

Usage

om_read(filename)

Arguments

filename

a geopackage file

Value

A list of map layers is returned.

Examples

res = om_get(c(-61.070, 14.605), r = 600)
om_map(res, title = "Fort-de-France town centre")
om_write(res, file.path(tempdir(), "f2f.gpkg"))
r = om_read(file.path(tempdir(), "f2f.gpkg"))
om_map(r, theme = "grey")

---

Save map layers to a file

Description

Write a list a map of layers to a geopackage file.

Usage

om_write(x, filename)

Arguments

x	a list of map layers produce with om_get
filename	a geopackage file

Value

The layers are saved to a geopackage file. Nothing is returned.

Examples

res = om_get(c(-61.070, 14.605), r = 600)
om_map(res, title = "Fort-de-France town centre")
(om_write(res, file.path(tempdir(), "f2f.gpkg")))

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