This function retrieves elevation data from the USGS national map API and converts it into a matrix appropriate for further usage with tools such as rayshader. It requires a functioning internet connection to retrieve data.
get_heightmap( bbox, img.width = 600, img.height = 600, lat = NULL, lng = NULL, save.tif = FALSE, tif.filename = NULL, sr_bbox = 4326, sr_image = 4326, verbose = FALSE )
bbox | Bounding box to download imagery for |
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img.width | Image width, in pixels |
img.height | Image size, in pixels |
lat | A quoted string indicating what named value in the bounding box represents latitude. If NULL, will be inferred from bounding box names. |
lng | A quoted string indicating what named value in the bounding box represents longitude. If NULL, will be inferred from bounding box names. |
save.tif | Logical: should the downloaded imagery be saved as a file? |
tif.filename | If |
sr_bbox | Spatial reference code (ISO 19111) for bounding box |
sr_image | Spatial reference code (ISO 19111) for image |
verbose | Logical: print out debug information while trying to query the elevation map server? |
A matrix object containing elevation data suitable for use with mapping functions. Returned invisibly.
if (FALSE) { bbox <- get_centroid_bounding_box(c( "lat" = 44.121268, "lng" = -73.903734 ), distance = 10 ) heightmap <- get_heightmap(bbox) }