# terrain_tiles_open.ludic — a map's baked tiles opened for the CPU questions alone (terrain_height,
# terrain_height_file, _smooth, terrain_ortho), with no device and no renderer booted: for a bake, a
# migration or a test that asks the ground of a map it will never draw.

# the bake at `path` (its key and version as terrain_from_baked takes them) opened for reading, the map
# `half` metres each way from (ox, oz); false (nothing changed) when it is not this bake, or when the
# whole copy is kept - that one answers first, so opening tiles under it would be read by nothing
@alloc_ok("a map's tiles opened once, for a bake or a test")
export function terrain_tiles_open_file(render3d_st: mut Render3dState, path: string, key: string, version: int, half: int, ox: float, oz: float) -> bool {
  if render3d_st.ter_heights != null { return false }
  let base = ltt2_bake_base(path, key, version)
  if base < 0 { return false }
  render3d_st.TERRAIN_HALF = half
  render3d_st.ter_ox = ox
  render3d_st.ter_oz = oz
  render3d_st.ter_h_scale = 0.0
  render3d_st.ter_o_scale = 0.0
  return tt_open_ltt2(render3d_st, path, base)
}