Transform rasters and write manifest file for import into Unity

These functions crop input raster files into smaller square tiles and then converts them into either .png or .raw files which are ready to be imported into the Unity game engine. make_manifest also writes a "manifest" file and importer script which may be used to automatically import the tiles into Unity.

Usage

make_manifest(
  heightmap,
  overlay = NULL,
  output_prefix = "import",
  manifest_path = "terrainr.manifest",
  importer_path = "import_terrain.cs"
)

transform_elevation(heightmap, side_length = 4097, output_prefix = "import")

transform_overlay(overlay, side_length = 4097, output_prefix = "import")

Arguments

heightmap

File path to the heightmap to transform.

overlay

File path to the image overlay to transform. Optional for make_manifest.

output_prefix

The file path to prefix output tiles with.

manifest_path

File path to write the manifest file to.

importer_path

File name to write the importer script to. Set to NULL to not copy the importer script. Will overwrite any file at the same path.

side_length

Side length, in pixels, of each output tile. If the raster has dimensions not evenly divisible by side_length, tiles will be generated with overhanging pieces set to 0 units of elevation or RGB 0 (pure black). Side lengths not equal to 2^x + 1 (for x <= 12) will cause a warning, as tiles must be this size for import into Unity.

Value

manifest_path, invisibly.

Examples

if (FALSE) {
if (!isTRUE(as.logical(Sys.getenv("CI")))) {
  simulated_data <- data.frame(
    id = seq(1, 100, 1),
    lat = runif(100, 44.04905, 44.17609),
    lng = runif(100, -74.01188, -73.83493)
  )
  simulated_data <- sf::st_as_sf(simulated_data, coords = c("lng", "lat"))
  output_files <- get_tiles(simulated_data)
  temptiff <- tempfile(fileext = ".tif")
  merge_rasters(output_files["elevation"][[1]], temptiff)
  make_manifest(temptiff, output_prefix = tempfile(), importer_path = NULL)
}
}