Crop map to poster aspect ratio to reduce empty margins

create_map_poster.py

@@ -15,6 +15,11 @@ THEMES_DIR = "themes"
 FONTS_DIR = "fonts"
 POSTERS_DIR = "posters"
 
+# ---- Layout tuning (easy knobs) ----
+FIGSIZE = (12, 16)          # Poster size in inches
+MAP_POS = (0.03, 0.18, 0.94, 0.80)  # [left, bottom, width, height] in figure coords
+MAP_PAD = 0.03              # Crop padding fraction (3% margin)
+
 def load_fonts():
     """
     Load Roboto fonts from the fonts directory.
@@ -25,13 +30,13 @@ def load_fonts():
         'regular': os.path.join(FONTS_DIR, 'Roboto-Regular.ttf'),
         'light': os.path.join(FONTS_DIR, 'Roboto-Light.ttf')
     }
-    
+
     # Verify fonts exist
     for weight, path in fonts.items():
         if not os.path.exists(path):
             print(f"⚠ Font not found: {path}")
             return None
-    
+
     return fonts
 
 FONTS = load_fonts()
@@ -42,7 +47,7 @@ def generate_output_filename(city, theme_name):
     """
     if not os.path.exists(POSTERS_DIR):
         os.makedirs(POSTERS_DIR)
-    
+
     timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
     city_slug = city.lower().replace(' ', '_')
     filename = f"{city_slug}_{theme_name}_{timestamp}.png"
@@ -55,7 +60,7 @@ def get_available_themes():
     if not os.path.exists(THEMES_DIR):
         os.makedirs(THEMES_DIR)
         return []
-    
+
     themes = []
     for file in sorted(os.listdir(THEMES_DIR)):
         if file.endswith('.json'):
@@ -68,7 +73,7 @@ def load_theme(theme_name="feature_based"):
     Load theme from JSON file in themes directory.
     """
     theme_file = os.path.join(THEMES_DIR, f"{theme_name}.json")
-    
+
     if not os.path.exists(theme_file):
         print(f"⚠ Theme file '{theme_file}' not found. Using default feature_based theme.")
         # Fallback to embedded default theme
@@ -86,7 +91,7 @@ def load_theme(theme_name="feature_based"):
             "road_residential": "#4A4A4A",
             "road_default": "#3A3A3A"
         }
-    
+
     with open(theme_file, 'r') as f:
         theme = json.load(f)
         print(f"✓ Loaded theme: {theme.get('name', theme_name)}")
@@ -97,6 +102,37 @@ def load_theme(theme_name="feature_based"):
 # Load theme (can be changed via command line or input)
 THEME = None  # Will be loaded later
 
+def crop_axes_to_ratio(ax, target_ratio, pad=0.03):
+    """
+    Crop current ax limits to match target width/height ratio.
+    target_ratio = width/height
+    pad is a fraction (e.g. 0.03 = 3%) to keep small margins.
+    """
+    x0, x1 = ax.get_xlim()
+    y0, y1 = ax.get_ylim()
+
+    w = x1 - x0
+    h = y1 - y0
+    if w <= 0 or h <= 0:
+        return
+
+    cx = (x0 + x1) / 2
+    cy = (y0 + y1) / 2
+    current_ratio = w / h
+
+    shrink = max(0.0, min(0.2, float(pad)))
+
+    if current_ratio > target_ratio:
+        # too wide -> reduce width
+        new_w = h * target_ratio
+        new_w *= (1 - shrink)
+        ax.set_xlim(cx - new_w / 2, cx + new_w / 2)
+    else:
+        # too tall -> reduce height
+        new_h = w / target_ratio
+        new_h *= (1 - shrink)
+        ax.set_ylim(cy - new_h / 2, cy + new_h / 2)
+
 def create_gradient_fade(ax, color, location='bottom', zorder=10):
     """
     Creates a fade effect at the top or bottom of the map
@@ -151,15 +187,15 @@ def get_edge_colors_by_type(G):
     Returns a list of colors corresponding to each edge in the graph.
     """
     edge_colors = []
-    
+
     for u, v, data in G.edges(data=True):
         # Get the highway type (can be a list or string)
         highway = data.get('highway', 'unclassified')
-        
+
         # Handle list of highway types (take the first one)
         if isinstance(highway, list):
             highway = highway[0] if highway else 'unclassified'
-        
+
         # Assign color based on road type
         if highway in ['motorway', 'motorway_link']:
             color = THEME['road_motorway']
@@ -173,9 +209,9 @@ def get_edge_colors_by_type(G):
             color = THEME['road_residential']
         else:
             color = THEME['road_default']
-        
+
         edge_colors.append(color)
-    
+
     return edge_colors
 
 def get_edge_widths_by_type(G):
@@ -184,13 +220,13 @@ def get_edge_widths_by_type(G):
     Major roads get thicker lines.
     """
     edge_widths = []
-    
+
     for u, v, data in G.edges(data=True):
         highway = data.get('highway', 'unclassified')
-        
+
         if isinstance(highway, list):
             highway = highway[0] if highway else 'unclassified'
-        
+
         # Assign width based on road importance
         if highway in ['motorway', 'motorway_link']:
             width = 1.2
@@ -202,9 +238,9 @@ def get_edge_widths_by_type(G):
             width = 0.6
         else:
             width = 0.4
-        
+
         edge_widths.append(width)
-    
+
     return edge_widths
 
 def get_coordinates(city, country):
@@ -214,12 +250,12 @@ def get_coordinates(city, country):
     """
     print("Looking up coordinates...")
     geolocator = Nominatim(user_agent="city_map_poster")
-    
+
     # Add a small delay to respect Nominatim's usage policy
     time.sleep(1)
-    
+
     location = geolocator.geocode(f"{city}, {country}")
-    
+
     if location:
         print(f"✓ Found: {location.address}")
         print(f"✓ Coordinates: {location.latitude}, {location.longitude}")
@@ -229,7 +265,7 @@ def get_coordinates(city, country):
 
 def create_poster(city, country, point, dist, output_file):
     print(f"\nGenerating map for {city}, {country}...")
-    
+
     # Progress bar for data fetching
     with tqdm(total=3, desc="Fetching map data", unit="step", bar_format='{l_bar}{bar}| {n_fmt}/{total_fmt}') as pbar:
         # 1. Fetch Street Network
@@ -237,7 +273,7 @@ def create_poster(city, country, point, dist, output_file):
         G = ox.graph_from_point(point, dist=dist, dist_type='bbox', network_type='all')
         pbar.update(1)
         time.sleep(0.5)  # Rate limit between requests
-        
+
         # 2. Fetch Water Features
         pbar.set_description("Downloading water features")
         try:
@@ -246,7 +282,7 @@ def create_poster(city, country, point, dist, output_file):
             water = None
         pbar.update(1)
         time.sleep(0.3)
-        
+
         # 3. Fetch Parks
         pbar.set_description("Downloading parks/green spaces")
         try:
@@ -254,27 +290,46 @@ def create_poster(city, country, point, dist, output_file):
         except:
             parks = None
         pbar.update(1)
-    
+
     print("✓ All data downloaded successfully!")
-    
+
+    # --- Project to metric CRS (stabilizes aspect + enables correct cropping) ---
+    G = ox.project_graph(G)
+    crs = G.graph.get("crs", None)
+
+    if crs is not None:
+        try:
+            if water is not None and hasattr(water, "to_crs") and not water.empty:
+                water = water.to_crs(crs)
+        except:
+            pass
+        try:
+            if parks is not None and hasattr(parks, "to_crs") and not parks.empty:
+                parks = parks.to_crs(crs)
+        except:
+            pass
+
     # 2. Setup Plot
     print("Rendering map...")
-    fig, ax = plt.subplots(figsize=(12, 16), facecolor=THEME['bg'])
+    fig, ax = plt.subplots(figsize=FIGSIZE, facecolor=THEME['bg'])
     ax.set_facecolor(THEME['bg'])
-    ax.set_position([0, 0, 1, 1])
-    
+
+    # Reserve a dedicated map area (leave room for bottom typography)
+    ax.set_position(list(MAP_POS))
+    map_h_frac = MAP_POS[3]
+
     # 3. Plot Layers
     # Layer 1: Polygons
-    if water is not None and not water.empty:
+    if water is not None and not getattr(water, "empty", True):
         water.plot(ax=ax, facecolor=THEME['water'], edgecolor='none', zorder=1)
-    if parks is not None and not parks.empty:
+    if parks is not None and not getattr(parks, "empty", True):
         parks.plot(ax=ax, facecolor=THEME['parks'], edgecolor='none', zorder=2)
-    
+
     # Layer 2: Roads with hierarchy coloring
     print("Applying road hierarchy colors...")
     edge_colors = get_edge_colors_by_type(G)
     edge_widths = get_edge_widths_by_type(G)
-    
+
     ox.plot_graph(
         G, ax=ax, bgcolor=THEME['bg'],
         node_size=0,
@@ -282,42 +337,45 @@ def create_poster(city, country, point, dist, output_file):
         edge_linewidth=edge_widths,
         show=False, close=False
     )
-    
+
+    # Crop view to match the poster/map area aspect ratio (in projected units)
+    fig_w, fig_h = fig.get_size_inches()
+    target_ratio = fig_w / (fig_h * map_h_frac)  # width/height of the map area
+    crop_axes_to_ratio(ax, target_ratio=target_ratio, pad=MAP_PAD)
+
     # Layer 3: Gradients (Top and Bottom)
     create_gradient_fade(ax, THEME['gradient_color'], location='bottom', zorder=10)
-    create_gradient_fade(ax, THEME['gradient_color'], location='top', zorder=10) 
-    
+    create_gradient_fade(ax, THEME['gradient_color'], location='top', zorder=10)
+
     # 4. Typography using Roboto font
     if FONTS:
         font_main = FontProperties(fname=FONTS['bold'], size=60)
-        font_top = FontProperties(fname=FONTS['bold'], size=40)
         font_sub = FontProperties(fname=FONTS['light'], size=22)
         font_coords = FontProperties(fname=FONTS['regular'], size=14)
     else:
         # Fallback to system fonts
         font_main = FontProperties(family='monospace', weight='bold', size=60)
-        font_top = FontProperties(family='monospace', weight='bold', size=40)
         font_sub = FontProperties(family='monospace', weight='normal', size=22)
         font_coords = FontProperties(family='monospace', size=14)
-    
+
     spaced_city = "  ".join(list(city.upper()))
 
     # --- BOTTOM TEXT ---
     ax.text(0.5, 0.14, spaced_city, transform=ax.transAxes,
             color=THEME['text'], ha='center', fontproperties=font_main, zorder=11)
-    
+
     ax.text(0.5, 0.10, country.upper(), transform=ax.transAxes,
             color=THEME['text'], ha='center', fontproperties=font_sub, zorder=11)
-    
+
     lat, lon = point
     coords = f"{lat:.4f}° N / {lon:.4f}° E" if lat >= 0 else f"{abs(lat):.4f}° S / {lon:.4f}° E"
     if lon < 0:
         coords = coords.replace("E", "W")
-    
+
     ax.text(0.5, 0.07, coords, transform=ax.transAxes,
             color=THEME['text'], alpha=0.7, ha='center', fontproperties=font_coords, zorder=11)
-    
-    ax.plot([0.4, 0.6], [0.125, 0.125], transform=ax.transAxes, 
+
+    ax.plot([0.4, 0.6], [0.125, 0.125], transform=ax.transAxes,
             color=THEME['text'], linewidth=1, zorder=11)
 
     # --- ATTRIBUTION (bottom right) ---
@@ -325,9 +383,9 @@ def create_poster(city, country, point, dist, output_file):
         font_attr = FontProperties(fname=FONTS['light'], size=8)
     else:
         font_attr = FontProperties(family='monospace', size=8)
-    
+
     ax.text(0.98, 0.02, "© OpenStreetMap contributors", transform=ax.transAxes,
-            color=THEME['text'], alpha=0.5, ha='right', va='bottom', 
+            color=THEME['text'], alpha=0.5, ha='right', va='bottom',
             fontproperties=font_attr, zorder=11)
 
     # 5. Save
@@ -349,30 +407,30 @@ Examples:
   # Iconic grid patterns
   python create_map_poster.py -c "New York" -C "USA" -t noir -d 12000           # Manhattan grid
   python create_map_poster.py -c "Barcelona" -C "Spain" -t warm_beige -d 8000   # Eixample district grid
-  
+
   # Waterfront & canals
   python create_map_poster.py -c "Venice" -C "Italy" -t blueprint -d 4000       # Canal network
   python create_map_poster.py -c "Amsterdam" -C "Netherlands" -t ocean -d 6000  # Concentric canals
   python create_map_poster.py -c "Dubai" -C "UAE" -t midnight_blue -d 15000     # Palm & coastline
-  
+
   # Radial patterns
   python create_map_poster.py -c "Paris" -C "France" -t pastel_dream -d 10000   # Haussmann boulevards
   python create_map_poster.py -c "Moscow" -C "Russia" -t noir -d 12000          # Ring roads
-  
+
   # Organic old cities
   python create_map_poster.py -c "Tokyo" -C "Japan" -t japanese_ink -d 15000    # Dense organic streets
   python create_map_poster.py -c "Marrakech" -C "Morocco" -t terracotta -d 5000 # Medina maze
   python create_map_poster.py -c "Rome" -C "Italy" -t warm_beige -d 8000        # Ancient street layout
-  
+
   # Coastal cities
   python create_map_poster.py -c "San Francisco" -C "USA" -t sunset -d 10000    # Peninsula grid
   python create_map_poster.py -c "Sydney" -C "Australia" -t ocean -d 12000      # Harbor city
   python create_map_poster.py -c "Mumbai" -C "India" -t contrast_zones -d 18000 # Coastal peninsula
-  
+
   # River cities
   python create_map_poster.py -c "London" -C "UK" -t noir -d 15000              # Thames curves
   python create_map_poster.py -c "Budapest" -C "Hungary" -t copper_patina -d 8000  # Danube split
-  
+
   # List themes
   python create_map_poster.py --list-themes
 
@@ -398,7 +456,7 @@ def list_themes():
     if not available_themes:
         print("No themes found in 'themes/' directory.")
         return
-    
+
     print("\nAvailable Themes:")
     print("-" * 60)
     for theme_name in available_themes:
@@ -429,57 +487,57 @@ Examples:
   python create_map_poster.py --list-themes
         """
     )
-    
+
     parser.add_argument('--city', '-c', type=str, help='City name')
     parser.add_argument('--country', '-C', type=str, help='Country name')
     parser.add_argument('--theme', '-t', type=str, default='feature_based', help='Theme name (default: feature_based)')
     parser.add_argument('--distance', '-d', type=int, default=29000, help='Map radius in meters (default: 29000)')
     parser.add_argument('--list-themes', action='store_true', help='List all available themes')
-    
+
     args = parser.parse_args()
-    
+
     # If no arguments provided, show examples
     if len(os.sys.argv) == 1:
         print_examples()
         os.sys.exit(0)
-    
+
     # List themes if requested
     if args.list_themes:
         list_themes()
         os.sys.exit(0)
-    
+
     # Validate required arguments
     if not args.city or not args.country:
         print("Error: --city and --country are required.\n")
         print_examples()
         os.sys.exit(1)
-    
+
     # Validate theme exists
     available_themes = get_available_themes()
     if args.theme not in available_themes:
         print(f"Error: Theme '{args.theme}' not found.")
         print(f"Available themes: {', '.join(available_themes)}")
         os.sys.exit(1)
-    
+
     print("=" * 50)
     print("City Map Poster Generator")
     print("=" * 50)
-    
+
     # Load theme
     THEME = load_theme(args.theme)
-    
+
     # Get coordinates and generate poster
     try:
         coords = get_coordinates(args.city, args.country)
         output_file = generate_output_filename(args.city, args.theme)
         create_poster(args.city, args.country, coords, args.distance, output_file)
-        
+
         print("\n" + "=" * 50)
         print("✓ Poster generation complete!")
         print("=" * 50)
-        
+
     except Exception as e:
         print(f"\n✗ Error: {e}")
         import traceback
         traceback.print_exc()
-        os.sys.exit(1)
+        os.sys.exit(1)