import math
import requests
import os
def latlon_to_tile(lat, lon, z):
lat_rad = math.radians(lat)
n = 2.0 ** z
xtile = int((lon + 180.0) / 360.0 * n)
ytile = int((1.0 - math.asinh(math.tan(lat_rad)) / math.pi) / 2.0 * n)
return xtile, ytile
def download_tile(lat, lon, z=12, output_dir="dted"):
x, y = latlon_to_tile(lat, lon, z)
url = f"https://s3.amazonaws.com/elevation-tiles-prod/geotiff/{z}/{x}/{y}.tif"
filename = f"{output_dir}/aws_z{z}_x{x}_y{y}.tif"
print(f"Downloading tile for {lat}, {lon} (Tile: {z}/{x}/{y})...")
print(f"URL: {url}")
try:
r = requests.get(url, stream=True)
if r.status_code == 200:
os.makedirs(output_dir, exist_ok=True)
with open(filename, 'wb') as f:
for chunk in r.iter_content(chunk_size=8192):
f.write(chunk)
print(f"Saved to {filename}")
return filename
else:
print(f"Failed: {r.status_code}")
return None
except Exception as e:
print(f"Error: {e}")
return None
if __name__ == "__main__":
# Download a few tiles around Grand Canyon
# Center: 36.1, -112.1
download_tile(36.1, -112.1, z=12)
download_tile(36.1, -112.2, z=12) # Adjacent
print("\nDone! Restart the server to load these tiles.")
print("Test coordinates: 36.1, -112.1")
