In CRAN or offline builds, network-dependent chunks are not evaluated.
New York Harbor is the primary public AOI for the examples, but its current small plan is a compatible 4 m grid. This example uses BlueTopo tiles covering Key West and Boca Chica Channel because the documented secondary AOI currently intersects 4 m and 8 m source grids and therefore demonstrates mixed native-grid behavior.
Mixed native grids are preserved unless the user asks for a single
output grid. combine = "single" needs an explicit output
grid when native grids are incompatible. Resampled uncertainty values
are not original source cells, and contributor resampling must be
nearest-neighbor.
single <- suppressWarnings(bluertopo(
real_aoi,
layers = "elevation",
resolution = "native",
coverage = "fill",
output_crs = "EPSG:26917",
output_resolution = 100,
combine = "single",
details = TRUE,
progress = FALSE,
quiet = TRUE
))The explicit grid is useful for workflows that require one raster, but it is a resampling operation. Native source-resolution selection remains separate from output-grid creation.