Extract elevation with terra

In CRAN or offline builds, network-dependent chunks are not evaluated.

This example uses BlueTopo tiles covering New York Harbor. The workflow demonstrates tile discovery, checksum-verified asset retrieval, and file-backed raster access with terra. Raster Attribute Table (RAT) sidecars are retained with the source GeoTIFF assets.

bluertopo() returns terra objects and, with details = TRUE, exposes selected tiles, downloads, query metadata, provenance, and coverage diagnostics. Normal native extraction does not intentionally resample.

Example area

Extract elevation

result <- bluertopo(
  real_aoi,
  layers = "elevation",
  resolution = "native",
  coverage = "fill",
  details = TRUE,
  progress = FALSE,
  quiet = TRUE
)

Object summary

File-backed sources

Coverage

Provenance

Elevation preview

When native source grids differ, the result can be a SpatRasterCollection. Each member can still be file-backed by verified original assets.