Update ash_animator/basemaps.py

ash_animator/basemaps.py

@@ -8,46 +8,47 @@ import cartopy.crs as ccrs
 import cartopy.feature as cfeature
 
 def get_cache_dir(app_name):
+    """
+    Returns a writable cache directory path depending on the OS.
+    Linux: tries /code/<app>_cache, falls back to /tmp/<app>_cache
+    Windows: uses LOCALAPPDATA/<app>_cache
+    """
     if os.name == 'nt':
-        # Windows: Use LOCALAPPDATA or fallback to cwd
-        return os.path.join(os.getenv('LOCALAPPDATA', os.getcwd()), f"{app_name}_cache")
+        # Windows
+        base_dir = os.getenv('LOCALAPPDATA', os.getcwd())
     else:
-        # Unix: Try /code/app_name_cache, fallback to /tmp
+        # Unix
         base_dir = "/code"
-        cache_path = os.path.join(base_dir, f"{app_name}_cache")
         try:
-            os.makedirs(cache_path, exist_ok=True)
-            os.chmod(cache_path, 0o777)
+            test_path = os.path.join(base_dir, f"{app_name}_cache")
+            os.makedirs(test_path, exist_ok=True)
+            os.chmod(test_path, 0o777)
+            return test_path
         except PermissionError:
-            print(f"[PermissionError] Cannot write to {cache_path}. Falling back to /tmp.")
-            cache_path = os.path.join("/tmp", f"{app_name}_cache")
-            os.makedirs(cache_path, exist_ok=True)
-        return cache_path
+            print(f"[PermissionError] Cannot use {base_dir}, falling back to /tmp.")
+            base_dir = "/tmp"
+    
+    cache_path = os.path.join(base_dir, f"{app_name}_cache")
+    os.makedirs(cache_path, exist_ok=True)
+    return cache_path
 
-# Define cache dirs
+# Setup cache directories
 CTX_TILE_CACHE_DIR = get_cache_dir("contextily")
 BASEMAP_TILE_CACHE_DIR = get_cache_dir("basemap")
 CARTOPY_CACHE_DIR = get_cache_dir("cartopy")
 
-# Set environment variables for Cartopy
+# Set Cartopy environment variables
 os.environ["CARTOPY_USER_BACKGROUNDS"] = CARTOPY_CACHE_DIR
 os.environ["CARTOPY_CACHE_DIR"] = CARTOPY_CACHE_DIR
 
-# Ensure cache dirs exist
-os.makedirs(CTX_TILE_CACHE_DIR, exist_ok=True)
-os.makedirs(BASEMAP_TILE_CACHE_DIR, exist_ok=True)
-
 def draw_etopo_basemap(ax, mode="basemap", zoom=11):
     """
-    Draws a high-resolution basemap background on the provided Cartopy GeoAxes.
+    Draws a basemap onto a Cartopy GeoAxes object.
     Parameters
     ----------
-    ax : matplotlib.axes._subplots.AxesSubplot
-        The matplotlib Axes object (with Cartopy projection) to draw the map background on.
-    mode : str, optional
-        The basemap mode to use: "stock", "contextily", "basemap".
-    zoom : int, optional
-        Tile zoom level for contextily.
+    ax : Cartopy GeoAxes
+    mode : 'stock' | 'contextily' | 'basemap'
+    zoom : int (contextily zoom level)
     """
     try:
         if mode == "stock":
@@ -61,7 +62,7 @@ def draw_etopo_basemap(ax, mode="basemap", zoom=11):
 
         elif mode == "basemap":
             extent = ax.get_extent(crs=ccrs.PlateCarree())
-            extent_str = f"{extent[0]:.4f}_{extent[1]:.4f}_{extent[2]:.4f}_{extent[3]:.4f}"
+            extent_str = "_".join(f"{v:.4f}" for v in extent)
             cache_key = hashlib.md5(extent_str.encode()).hexdigest()
             cache_file = os.path.join(BASEMAP_TILE_CACHE_DIR, f"{cache_key}_highres.png")
 
@@ -69,8 +70,8 @@ def draw_etopo_basemap(ax, mode="basemap", zoom=11):
                 img = Image.open(cache_file)
                 ax.imshow(img, extent=extent, transform=ccrs.PlateCarree())
             else:
-                temp_fig, temp_ax = plt.subplots(figsize=(12, 9),
-                                                 subplot_kw={'projection': ccrs.PlateCarree()})
+                fig, temp_ax = plt.subplots(figsize=(12, 9),
+                                            subplot_kw={'projection': ccrs.PlateCarree()})
                 temp_ax.set_extent(extent, crs=ccrs.PlateCarree())
 
                 m = Basemap(projection='cyl',
@@ -79,8 +80,8 @@ def draw_etopo_basemap(ax, mode="basemap", zoom=11):
                             resolution='f', ax=temp_ax)
 
                 m.shadedrelief()
-                temp_fig.savefig(cache_file, dpi=300, bbox_inches='tight', pad_inches=0)
-                plt.close(temp_fig)
+                fig.savefig(cache_file, dpi=300, bbox_inches='tight', pad_inches=0)
+                plt.close(fig)
 
                 img = Image.open(cache_file)
                 ax.imshow(img, extent=extent, transform=ccrs.PlateCarree())
@@ -89,6 +90,6 @@ def draw_etopo_basemap(ax, mode="basemap", zoom=11):
             raise ValueError(f"Unsupported basemap mode: {mode}")
 
     except Exception as e:
-        print(f"[Relief Error - {mode} mode]:", e)
+        print(f"[Basemap Error: {mode}] {e}")
         ax.add_feature(cfeature.LAND)
         ax.add_feature(cfeature.OCEAN)