def test_srtm3_height_map_collection_load_area():
collection = Srtm3HeightMapCollection()
collection.build_file_index()
collection.load_area(
RasterBaseCoordinates.from_file_name("N38W006"),
RasterBaseCoordinates.from_file_name("N40W008"),
)
loaded_height_maps = [
hm for hm in collection.height_maps.values() if hm.raster
]
assert len(loaded_height_maps) == 9
def __init__(self,
path: Path,
base_coordinates: RasterBaseCoordinates = None):
self.path = path
self.base_coordinates = (base_coordinates
or RasterBaseCoordinates.from_file_path(path))
# We subtract one as each row overlaps the neighbouring raster by 1 pixel
self.pixel_width = 1 / (self.values_per_row - 1)
def get_height_map_for_latitude_and_longitude(
self, latitude: float, longitude: float) -> HeightMap:
"""Get the HeightMap for the given latitude and longitude"""
base = RasterBaseCoordinates.from_float(latitude, longitude)
try:
return self.height_maps[base]
except KeyError:
raise Exception(
f"Height map for {base} not found. Have you called "
f"build_file_index() on your heightmap collection?")
def build_file_index(self):
"""Load an index of all available files
This reads file names, but does not load the contained data.
This is lazy-loaded on demand
"""
self.height_maps = {}
for hgt_path in self.hgt_dir.glob("**/*.hgt*"):
hgt_name = hgt_path.name.split(".")[0]
self.height_maps[RasterBaseCoordinates.from_file_name(
hgt_name)] = self.height_map_class(path=hgt_path)
def get_height_map_for_latitude_and_longitude(
self, latitude: float, longitude: float) -> HeightMap:
"""Get the HeightMap for the given latitude and longitude"""
base = RasterBaseCoordinates.from_float(latitude, longitude)
try:
return self.height_maps[base]
except KeyError:
raise NoHeightMapDataException(
f"Height map for {base} not found. Either your the SRTM directory "
f"'{self.hgt_dir}' is missing files, or you have set auto_build_index=False "
f"and therefore need to manually call build_file_index(). It is probably "
f"the former.")
def test_raster_base_coordinates_from_file_name_sw():
assert RasterBaseCoordinates.from_file_name("S40W005") == (-40, -5)
def test_raster_base_coordinates_from_file_name_ne():
assert RasterBaseCoordinates.from_file_name("N40E005") == (40, 5)
def test_raster_base_coordinates_zero():
assert (RasterBaseCoordinates.from_float(
latitude=0.1,
longitude=0.1,
).file_name == "N00E000")
def test_raster_base_coordinates_ne():
assert (RasterBaseCoordinates.from_float(
latitude=40.1,
longitude=5.1,
).file_name == "N40E005")
def test_raster_base_coordinates_sw():
assert (RasterBaseCoordinates.from_float(
latitude=-7.956037,
longitude=-14.357948,
).file_name == "S08W015")
def test_raster_base_coordinates_se():
assert (RasterBaseCoordinates.from_float(
latitude=-33.768549,
longitude=18.504695,
).file_name == "S34E018")
def test_raster_base_coordinates_nw():
assert (RasterBaseCoordinates.from_float(
latitude=40.1,
longitude=-7.1,
).file_name == "N40W008")