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Add stars layer to a leaflet map

Usage

addStarsImage(
  map,
  x,
  band = 1,
  colors = "Spectral",
  opacity = 1,
  attribution = NULL,
  layerId = NULL,
  group = NULL,
  project = FALSE,
  method = c("auto", "bilinear", "near"),
  maxBytes = 4 * 1024 * 1024,
  options = gridOptions(),
  data = getMapData(map),
  ...
)

Arguments

map

a mapview or leaflet object.

x

a stars layer.

band

the band number to be plotted.

colors

the color palette (see colorNumeric) or function to use to color the raster values (hint: if providing a function, set na.color to "#00000000" to make NA areas transparent). The palette is ignored if x is a SpatRaster with a color table or if it has RGB channels.

opacity

the base opacity of the raster, expressed from 0 to 1

attribution

the HTML string to show as the attribution for this layer

layerId

the layer id

group

the name of the group this raster image should belong to (see the same parameter under addTiles)

project

if TRUE, automatically project x to the map projection expected by Leaflet (EPSG:3857); if FALSE, it's the caller's responsibility to ensure that x is already projected, and that extent(x) is expressed in WGS84 latitude/longitude coordinates

method

the method used for computing values of the new, projected raster image. "bilinear" (the default) is appropriate for continuous data, "ngb" - nearest neighbor - is appropriate for categorical data. Ignored if project = FALSE. See projectRaster for details.

maxBytes

the maximum number of bytes to allow for the projected image (before base64 encoding); defaults to 4MB.

options

a list of additional options, intended to be provided by a call to gridOptions

data

the data object from which the argument values are derived; by default, it is the data object provided to leaflet() initially, but can be overridden.

...

currently not used.

Details

This is an adaption of addRasterImage. See that documentation for details.

Examples

# \donttest{
library(stars)
library(leaflet)

tif = system.file("tif/L7_ETMs.tif", package = "stars")
x = read_stars(tif)
leaflet() %>%
  addProviderTiles("OpenStreetMap") %>%
  addStarsImage(x, project = TRUE)
#> Warning: no_data_value not set: missing values will appear as zero values
# }