[Python] Google Maps API - How to calculate the zoom level for a given coordinates

I have the following code:

def calculate_zoom_level(lat_diff, long_diff, map_width, map_height):
# Earth's circumference in degrees
WORLD_DIM = 256 # Tile size in pixels
ZOOM_MAX = 12 # Maximum zoom level (as used in the provided example)
MIN_DIFF = 0.000001 # Small value to prevent zero division

# A formula based on the map's bounds and dimensions to calculate zoom
def zoom_level(diff, map_dim):
# Avoid division by zero by using a minimum difference threshold
if diff == 0:
diff = MIN_DIFF
PADDING = 1.5 # Padding factor to leave space around the markers
return math.log2((360 / diff) * (map_dim / WORLD_DIM)) - PADDING

# Calculate zoom based on both latitude and longitude
lat_based_zoom = zoom_level(lat_diff, map_height)
long_based_zoom = zoom_level(long_diff, map_width)

# Take the smaller zoom level for fitting both dimensions into the map
zoom = min(lat_based_zoom, long_based_zoom)

# Further zoom out if necessary (based on location differences)
if lat_diff < 0.1 and long_diff < 0.1:
zoom -= 1 # Zoom out if locations are very close

# Constrain the zoom level to the maximum zoom specified (maxZoom = 12)
zoom = max(7, min(zoom, ZOOM_MAX))

return round(zoom)

def load_polygon_coordinates():
with open('cleaned_fine.json', 'r', encoding='utf-8') as file:
polygon_data = json.load(file)
return polygon_data


def generate_map_url(locations, polygons):
base_url = "https://maps.googleapis.com/maps/api/staticmap?"

# Extract latitudes and longitudes and convert them to floats
lats, longs = zip(*[(float(lat), float(long)) for lat, long in locations])

# Calculate bounds
min_lat, max_lat = min(lats), max(lats)
min_long, max_long = min(longs), max(longs)

# Set the center of the map to the midpoint of the bounds
center_lat = (min_lat + max_lat) / 2
center_long = (min_long + max_long) / 2

# Define the map dimensions (width and height in pixels)
map_width = 640
map_height = 530

# Calculate zoom level dynamically
zoom = calculate_zoom_level(max_lat - min_lat, max_long - min_long, map_width, map_height)

# Generate the markers for locations
markers = '|'.join([f'color:red|{lat},{long}' for lat, long in locations])

# Attempt to create polygon paths
paths = []
for polygon in polygons:
if len(polygon) >= 3: # A polygon must have at least 3 points to form a closed shape
path = '|'.join([f'{lat},{long}' for lat, long in polygon])
# Ensure the polygon is closed by repeating the first point at the end
if polygon[0] != polygon[-1]:
path += f'|{polygon[0][0]},{polygon[0][1]}'
paths.append(f'color:0x00000000|weight:2|fillcolor:red|{path}')

# Set parameters for the static map API
params = {
'center': f'{center_lat},{center_long}',
'zoom': zoom,
'size': f'{map_width}x{map_height}',
'markers': markers,
'language': 'he',
'key': ''
}

# If no valid polygons are available, ensure only red markers are used
if paths:
params['path'] = paths

# Generate the map URL
url = base_url + urllib.parse.urlencode(params, doseq=True)

# Attempt to fetch the image to check if it generates correctly
try:
response = requests.get(url)
img = Image.open(BytesIO(response.content)) # This can raise the error you're seeing
except Exception as e:
print(f"Error generating map image: {e}")
# If there's an error, fallback to markers only
params.pop('path', None) # Remove path if it exists
url = base_url + urllib.parse.urlencode(params, doseq=True)

return url


The problem here is that sometimes there is too much zoom out on areas that are close to each other anyway. I expect that, according to the coordinates, the zoom will be reduced according to the areas it receives, and that it will not be cut in the middle or something, it will simply display the map in its entirety but only the important part, and not just a large zoom out regardless of the proximity of the locations to each other. I am attaching 2 pictures for you here. picture_1 picture_2 The picture with the number 1 written on it is the example of the map I expect it to be

The picture with the number 2 on it is my current map (with this code)

I expect it to be like picture number 1, dynamic zoom depending on the locations

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