Package 'inbospatial'

addWMSTiles() and addWMS() wrapper functions for WMS services

Description

The ⁠add_wms_*()⁠ functions are shorthand alternatives for a fully specified leaflet::addWMSTiles() or leaflet.extras2::addWMS() statement. Appropriate attribution is added to the Leaflet map depending on the layer.

Usage

add_wms_be_cartoweb(
  map,
  layer = c("topo", "topo_grey", "overlay", "crossborder"),
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE),
  ...
)

add_wms_be_ortho(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE),
  ...
)

add_wms_nl_ortho(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE),
  ...
)

add_wms_fl_grbmap(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE),
  ...
)

add_wms_fl_habitatmap(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 1200),
  add_wms_legend = FALSE,
  ...
)

add_wms_fl_habitatlabels(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE),
  ...
)

add_wms_fl_forestnature(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 600),
  add_wms_legend = FALSE,
  ...
)

add_wms_fl_agriculture(
  map,
  year,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 1200),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_nnb(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 600),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_natte_natuurparels(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 2000),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_ambitie_landschapstypen(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 2000),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_ambitie_natuurtypen(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html"),
  popupOptions = leaflet::popupOptions(maxWidth = 2000),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_landschapstypen(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html", minZoom = 13),
  popupOptions = leaflet::popupOptions(maxWidth = 2000),
  add_wms_legend = FALSE,
  ...
)

add_wms_nlnb_natuurtypen(
  map,
  options = leaflet::WMSTileOptions(format = "image/png", transparent = TRUE, info_format
    = "text/html", minZoom = 13),
  popupOptions = leaflet::popupOptions(maxWidth = 2000),
  add_wms_legend = FALSE,
  ...
)

Arguments

map	a map widget object created from leaflet()
layer	String that defines which layer to use, if the function supports more than one. In such case, the available strings are shown in the Usage section. The first value is used if missing.
options	a list of extra options for tile layers, popups, paths (circles, rectangles, polygons, ...), or other map elements
...	Further arguments passed to leaflet::addWMSTiles() or leaflet.extras2::addWMS().
popupOptions	A Vector of popupOptions() to provide popups
add_wms_legend	Logical. Is a legend to be added for this WMS? Note that the legend cannot be toggled on and off in the map; it is plotted as a separate, static legend.
year	Year to be applied in selecting the WMS

Details

On condition that these functions continue being maintained, using the shorthand functions should make your scripts more futureproof.

Value

A leaflet HTML widget object.

Abbreviations

Prefixes

be_

Belgium

fl_

Flanders

nl_

Netherlands

nlnb_

Netherlands: Province 'Noord-Brabant'

Suffixes

Background layers

_ortho

Orthophotographs

_cartoweb

Topographic Cartoweb layers (Belgium)

_grbmap

GRB basemap (Flanders; 'Grootschalig Referentiebestand')

Feature layers

_habitatmap

Natura 2000 habitat types

_habitatlabels

Natura 2000 habitat type labels

_forestnature

Public forest and nature areas managed by the Flemish Nature & Forest Agency

_agriculture

Parcels with the agricultural use in a specific year

_nnb

Netherlands; 'Natuurnetwerk Brabant (Rijk en Provincie NNB)'

_natte_natuurparels

Netherlands; 'Natte natuurparels'

_ambitie_landschapstypen

Netherlands; 'Natuurbeheerplan - Ambitiekaart Landschaptypen'

_ambitie_natuurtypen

Netherlands; 'Natuurbeheerplan - Ambitiekaart Natuurtypen'

_landschapstypen

Netherlands; 'Natuurbeheerplan - Beheertypenkaart_Landschaptypen'

_natuurtypen

Netherlands; 'Natuurbeheerplan - Beheertypenkaart Natuurtypen'

Author(s)

Floris Vanderhaeghe, https://github.com/florisvdh

See Also

Other topics on using web services: add_wmts_nl_brt(), check_ogc_collection(), get_coverage_wcs(), get_feature_ogc(), get_feature_wfs(), get_wcs_layers()

Examples

library(leaflet)
leaflet() |>
  setView(lng = 4.5, lat = 51.45, zoom = 11) |>
  add_wmts_nl_brt("grijs") |>
  add_wms_be_cartoweb("topo_grey") |>
  add_wms_fl_forestnature() |>
  add_wms_nlnb_nnb()

# It can also use mapview objects, if you first extract the leaflet map slot:
library(mapview)
kmi_stations <- sf::read_sf(
  system.file("extdata/kmi_stations.geojson", package = "inbospatial")
)
mapview(kmi_stations, map.types = "CartoDB.Positron")@map |>
  add_wms_be_cartoweb()
# alternative syntax:
## Not run: 
mapview(kmi_stations, map.types = "CartoDB.Positron") |>
  _@map |>
  add_wms_be_cartoweb()

## End(Not run)

---

addTiles() wrapper functions for WMTS services

Description

The ⁠add_wmts_*()⁠ functions are shorthand alternatives for a fully specified leaflet::addTiles() statement. Appropriate attribution is added to the Leaflet map depending on the layer.

Usage

add_wmts_nl_brt(map, layer = c("standaard", "grijs", "pastel", "water"), ...)

add_wmts_nl_ortho(map, ...)

Arguments

map	a map widget object created from leaflet()
layer	String that defines which layer to use, if the function supports more than one. In such case, the available strings are shown in the Usage section. The first value is used if missing.
...	Further arguments passed to leaflet::addTiles().

Details

On condition that these functions continue being maintained, using the shorthand functions should make your scripts more futureproof.

Value

A leaflet HTML widget object.

Abbreviations

Prefixes

be_

Belgium

nl_

Netherlands

Suffixes

_ortho

Orthophotographs

_brt

Topographic BRT layers (Netherlands; 'Basisregistratie Topografie')

Author(s)

Floris Vanderhaeghe, https://github.com/florisvdh

See Also

Other topics on using web services: add_wms_be_cartoweb(), check_ogc_collection(), get_coverage_wcs(), get_feature_ogc(), get_feature_wfs(), get_wcs_layers()

Examples

library(leaflet)
leaflet() |>
  setView(lng = 5.5, lat = 52.5, zoom = 9) |>
  add_wmts_nl_brt()
leaflet() |>
  setView(lng = 5.4, lat = 52.2, zoom = 14) |>
  add_wmts_nl_ortho()

---

Check if a collection exists in an OGC API Features service

Description

A lightweight helper function that queries the ⁠/collections⁠ endpoint of an OGC API using JSON. It verifies if a specified collection exists and provides a helpful error message with valid names if it does not.

Usage

check_ogc_collection(url, collection)

Arguments

url	A character string with the base URL of the OGC API.
collection	A character string with the ID of the collection to check.

Value

TRUE invisibly if the collection exists, otherwise throws an error.

See Also

Other topics on using web services: add_wms_be_cartoweb(), add_wmts_nl_brt(), get_coverage_wcs(), get_feature_ogc(), get_feature_wfs(), get_wcs_layers()

Examples

## Not run: 
api_url <- "https://geo.api.vlaanderen.be/Wegenregister/ogc/features/v1"
check <- check_ogc_collection(api_url, "Wegsegment")
check

# An informative error is thrown when collection does not exist
check <- try(check_ogc_collection(api_url, "foutieve_laag"))

## End(Not run)

---

Get a layer from a web coverage service within a bounding box

Description

The function sends a query to a WCS service, downloads it to a temporary file from which it is read with terra::rast() - if needed reprojected - and returned as a SpatRaster object

Usage

get_coverage_wcs(
  wcs = c("dtm", "dsm", "omz", "omw", "dhmv", "mercatornet"),
  bbox,
  layername,
  resolution,
  wcs_crs = c("EPSG:4258", "EPSG:31370"),
  output_crs = "EPSG:31370",
  bbox_crs = "EPSG:31370",
  version = c("1.0.0", "2.0.1"),
  ...
)

Arguments

wcs	One of "dtm", "dsm", "omz", "omw", "dhmv", "mercatornet"
bbox	An object of class bbox of length 4.
layername	Character string; name of the layer
resolution	Output resolution in meters
wcs_crs	Native CRS in which the raster layers are stored on the WCS
output_crs	Output CRS. May involve reprojection.
bbox_crs	CRS in which bbox coordinates are passed
version	WCS version to be used. Default is ⁠1.0.0⁠.
...	Additional key-value pairs passed on to the WCS query

Details

The following WCS services can currently be used:

• "omz": orthophotomosaic summer images Flanders

• "omw": orthophotomosaic winter images Flanders

• "dtm": digital terrain model Flanders

• "dsm": digital surface model Flanders

• "dhmv": digital elevation model Flanders (contains dtm and dsm data)

• "mercatornet": Public Download Service Flemish Government - department environment - cooperation MercatorNet

For more information, see metadata Vlaanderen:

https://metadata.vlaanderen.be/srv/eng/catalog.search#/search?any=WCS

Value

A SpatRaster object

See Also

Other topics on using web services: add_wms_be_cartoweb(), add_wmts_nl_brt(), check_ogc_collection(), get_feature_ogc(), get_feature_wfs(), get_wcs_layers()

Examples

## Not run: 
bbox <- sf::st_bbox(
  c(xmin = 155800, xmax = 155850, ymin = 132700, ymax = 132750),
  crs = sf::st_crs(31370)
)
get_coverage_wcs(
  wcs = "dsm",
  bbox = bbox,
  layername = "EL.GridCoverage.DSM",
  resolution = 1
)

## End(Not run)

---

Download features from an OGC API Features service

Description

get_feature_ogc() provides a modern alternative to get_feature_wfs(). It retrieves vector data from an OGC API Features service. See https://ogcapi.ogc.org.

Usage

get_feature_ogc(
  url,
  collection,
  bbox = NULL,
  datetime = NULL,
  properties = NULL,
  cql_filter = NULL,
  limit = NULL,
  crs = NULL,
  quiet = TRUE,
  ...
)

Arguments

url	A character string with the base URL of the OGC API (the landing page).
collection	A character string with the ID of the collection (layer).
bbox	A bounding box to filter features. Can be a numeric vector of length 4 (c(xmin, ymin, xmax, ymax)) or an object of class bbox (from sf::st_bbox()). Note: OGC APIs generally expect the bbox coordinates to be in WGS84 (EPSG:4326).
datetime	A character string representing a time instant or time interval (e.g., "2018-02-12T23:20:50Z" or "2018-02-12T00:00:00Z/2018-03-18T12:31:12Z").
properties	A character vector of specific column names to return.
cql_filter	A character string containing a CQL2-text filter to apply attribute or complex spatial filtering on the server. See Common Query Language filter specifications.
limit	Numeric. Maximum number of features to retrieve. If NULL (default), all available features will be fetched via automatic API pagination.
crs	Target Coordinate Reference System (CRS) as an EPSG code or CRS object. If provided, the output will be automatically transformed to this CRS.
quiet	Logical. Should the download progress be suppressed? Defaults to TRUE.
...	Additional name-value pairs passed on to httr2::req_url_query.

Value

An sf (simple feature) object.

See Also

Other topics on using web services: add_wms_be_cartoweb(), add_wmts_nl_brt(), check_ogc_collection(), get_coverage_wcs(), get_feature_wfs(), get_wcs_layers()

Examples

## Not run: 
# Base URL for the Digitaal Vlaanderen Wegenregister (Road Register)
api_url <- "https://geo.api.vlaanderen.be/Wegenregister/ogc/features/v1"

# 1. Basic usage: Fetch 10 road segments
roads_sample <- get_feature_ogc(
  url = api_url,
  collection = "Wegsegment",
  limit = 10
)

# 2. Spatial Filtering & CRS Transformation:
# Fetch features within a WGS84 bounding box and project to Belgian Lambert72
my_bbox <- sf::st_bbox(
  c(xmin = 4.39, ymin = 51.21, xmax = 4.40, ymax = 51.22),
  crs = sf::st_crs(4326)
)
roads_bbox <- get_feature_ogc(
  url = api_url,
  collection = "Wegsegment",
  bbox = my_bbox,
  crs = 31370
)

# Base URL for Historical Land Use (Ferraris map)
hist_url <- "https://geo.api.vlaanderen.be/HistLandgebruik/ogc/features/v1"

# 3. Attribute Selection:
# Fetch only specific columns
ferraris_lite <- get_feature_ogc(
  url = hist_url,
  collection = "Lgbrk1778",
  limit = 100,
  properties = c("KLASSE")
)

# 4. Advanced CQL2 Attribute Filtering:
# Filter features directly on the server
roads_filtered <- get_feature_ogc(
  url = api_url,
  collection = "Wegsegment",
  limit = 50,
  cql_filter = "morfologischeWegklasse = 'dienstweg'"
)

## End(Not run)

---

Get a layer from a web feature service

Description

This function constructs a URL request from its arguments and either reads in the resulting vector layer as a sf object or returns the number of features that are requested. The request is made up of key-value pairs and additional key-value pairs can be passed to the function. The full documentation for the WFS standard can be consulted from https://www.ogc.org/standards/wfs/.

Usage

get_feature_wfs(
  wfs,
  version = "2.0.0",
  layername = NULL,
  crs = NULL,
  bbox = NULL,
  filter = NULL,
  cql_filter = NULL,
  output_format = NULL,
  property_name = NULL,
  result_type = c("results", "hits"),
  ...
)

Arguments

wfs	Web address for the service which you want to query features from
version	Version number for the service. For instance "2.0.0".
layername	Optional name of a layer hosted by the web feature service
crs	Optional coordinate reference system to represent the features. For instance "EPSG:31370".
bbox	Optional bounding box. Pass this as a named vector with names "xmin", "xmax", "ymin", "ymax".
filter	Optional standard OGC filter specification
cql_filter	Optional Common Query Language filter. This currently only works if the WFS is hosted on a GeoServer.
output_format	Optional output format supported by the WFS.
property_name	Optional character string. Which fields or columns to return? If you want to specify multiple columns, separate them by a comma. The column containing the feature geometry is usually called geom, geometry or SHAPE.
result_type	For version "2.x.x", this can be either "results" (default) or "hits". The former returns the requested features, the latter returns the number of requested features.
...	Additional key-value pairs passed on to the WFS query.

Details

See https://tutorials.inbo.be/tutorials/spatial_wfs_services/ for more information.

Value

An sf (simple feature) object.

See Also

Other topics on using web services: add_wms_be_cartoweb(), add_wmts_nl_brt(), check_ogc_collection(), get_coverage_wcs(), get_feature_ogc(), get_wcs_layers()

Examples

## Not run: 
vlaanderen <- get_feature_wfs(
  wfs = paste0(
    "https://eservices.minfin.fgov.be/",
    "arcgis/services/R2C/Regions/MapServer/WFSServer"
  ),
  layername = "regions",
  crs = "EPSG:31370",
  filter = paste0(
    "<Filter><PropertyIsEqualTo><PropertyName>",
    "regions:NameDUT</PropertyName><Literal>'Vlaams Gewest'",
    "</Literal></PropertyIsEqualTo></Filter>"
  )
)

## End(Not run)

---

Get available layers from a web coverage service

Description

The function sends a GetCapabilities query to a WCS service, parses the XML response, and returns a data.frame containing the names of the available layers and their descriptions.

Usage

get_wcs_layers(
  wcs = c("dtm", "dsm", "omz", "omw", "dhmv", "mercatornet"),
  version = c("1.0.0", "2.0.1"),
  ...
)

Arguments

wcs	One of "dtm", "dsm", "omz", "omw", "dhmv", "mercatornet"
version	WCS version to be used. Default is ⁠1.0.0⁠.
...	Additional key-value pairs passed on to the WCS query

Details

The following WCS services can currently be used:

• "omz": orthophotomosaic summer images Flanders

• "omw": orthophotomosaic winter images Flanders

• "dtm": digital terrain model Flanders

• "dsm": digital surface model Flanders

• "dhmv": digital elevation model Flanders (contains dtm and dsm data)

• "mercatornet": Public Download Service Flemish Government - department environment - cooperation MercatorNet For more information, see metadata Vlaanderen: https://metadata.vlaanderen.be/srv/eng/catalog.search#/search?any=WCS

Value

A data.frame object with columns layername and description.

See Also

Other topics on using web services: add_wms_be_cartoweb(), add_wmts_nl_brt(), check_ogc_collection(), get_coverage_wcs(), get_feature_ogc(), get_feature_wfs()

Examples

## Not run: 
get_wcs_layers(wcs = "dsm")
get_wcs_layers(wcs = "omz", version = "2.0.1")

## End(Not run)

---

Return the scale factor for a specific parallel in a Lambert Conic Conformal projection

Description

The scale factor is the distance distortion. In this case (a conic conformal projection) it holds in any direction.

Usage

scalefactor_lcc(par_deg, par1_deg, par2_deg)

Arguments

par_deg	Numeric vector. The latitude in decimal degrees of one or more parallels for which to do the calculation.
par1_deg	Latitude of the first standard parallel of the LCC projection in decimal degrees.
par2_deg	Latitude of the second standard parallel of the LCC projection in decimal degrees.

Details

The function applies to normal LCC projections, not the oblique ones. The applied formulas are for the sphere, hence approximate.

Value

Numeric vector, same length as par_deg.

Author(s)

Floris Vanderhaeghe, https://github.com/florisvdh

References

Snyder J.P. (1987). Map Projections - A Working Manual. U.S. Geological Survey Professional Paper, Nr. 1395. United States Government Printing Office, Washington, 397 p.

See Also

Other functions to explore properties of coordinate reference systems: scalefactor_tcyl()

Examples

sf::st_crs(31370)
x <- seq(49.5, 52.5, 0.1)
y <- scalefactor_lcc(x, 51.1666672333333, 49.8333339)
data.frame(latitude = x, scalefactor = y)

---

Return the scale factor for the angular distance from the central meridian in an (unscaled) transverse cylindrical projection

Description

The scale factor is the distance distortion in the direction of the meridians. In the case of the Transverse Mercator projection (a cylindrical conformal projection) it holds in any direction.

Usage

scalefactor_tcyl(ang_dist)

Arguments

ang_dist

Numeric vector. One or more angular distances from the central meridian, in decimal degrees.

Details

The formulas applied are for the sphere, hence approximate.

The best known map projection system in this context is the Universal Transverse Mercator (UTM), which superposes a central meridian scale factor of 0.9996.

Value

Numeric vector, same length as ang_dist.

Author(s)

Floris Vanderhaeghe, https://github.com/florisvdh

References

Iliffe J. & Lott R. (2008). Datums and Map Projections. For Remote Sensing, GIS and Surveying. 2nd edn. Whittles Publishing, Caithness, UK, 208 p.

See Also

Other functions to explore properties of coordinate reference systems: scalefactor_lcc()

Examples

x <- seq(0, 3, 0.1)
y <- scalefactor_tcyl(x)
data.frame(ang_dist = x, scalefactor = y)

---