Simplify label positioning to clearance-threshold approach

Replace Gaussian-weighted blend with simpler algorithm: find all pixels with
>= 70% of max possible clearance, pick closest to centroid. This guarantees
labels stay well inside province boundaries while remaining centered.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main/csharp/net/eagle0/clients/unity/eagle0/Assets/Eagle/centroids.json

@@ -3,8 +3,8 @@
     {
       "id": 4,
       "name": "Berkorszag",
-      "centroid_x": 1757.8,
-      "centroid_y": 1231.9,
+      "centroid_x": 1737.0,
+      "centroid_y": 1296.0,
       "area": 247272,
       "orientation": -20.1884829564446,
       "principal_length": 873.5,
@@ -14,8 +14,8 @@
     {
       "id": 27,
       "name": "Chapellia",
-      "centroid_x": 3076.8,
-      "centroid_y": 508.9,
+      "centroid_x": 3077.0,
+      "centroid_y": 509.0,
       "area": 37546,
       "orientation": -70.52505264723656,
       "principal_length": 297.6,
@@ -25,8 +25,8 @@
     {
       "id": 28,
       "name": "Kezonoria",
-      "centroid_x": 2204.7,
-      "centroid_y": 1263.1,
+      "centroid_x": 2195.0,
+      "centroid_y": 1226.0,
       "area": 126885,
       "orientation": -35.386786918677814,
       "principal_length": 753.6,
@@ -36,7 +36,7 @@
     {
       "id": 29,
       "name": "Mesh",
-      "centroid_x": 2832.3,
+      "centroid_x": 2832.0,
       "centroid_y": 1017.0,
       "area": 197788,
       "orientation": -26.173956537897066,
@@ -47,8 +47,8 @@
     {
       "id": 36,
       "name": "Pemeria",
-      "centroid_x": 2839.4,
-      "centroid_y": 1290.4,
+      "centroid_x": 2835.0,
+      "centroid_y": 1282.0,
       "area": 36356,
       "orientation": -44.16012147839107,
       "principal_length": 457.1,
@@ -58,8 +58,8 @@
     {
       "id": 37,
       "name": "Yuetia",
-      "centroid_x": 896.1,
-      "centroid_y": 1227.1,
+      "centroid_x": 902.0,
+      "centroid_y": 1132.0,
       "area": 362211,
       "orientation": 0.6747576339005641,
       "principal_length": 1261.0,
@@ -69,8 +69,8 @@
     {
       "id": 39,
       "name": "Kojaria",
-      "centroid_x": 3233.1,
-      "centroid_y": 678.6,
+      "centroid_x": 3234.0,
+      "centroid_y": 678.0,
       "area": 37489,
       "orientation": -25.04939634407932,
       "principal_length": 301.9,
@@ -80,8 +80,8 @@
     {
       "id": 43,
       "name": "Chia",
-      "centroid_x": 1134.5,
-      "centroid_y": 1519.3,
+      "centroid_x": 1172.0,
+      "centroid_y": 1499.0,
       "area": 75627,
       "orientation": -35.91298964206631,
       "principal_length": 441.6,
@@ -91,8 +91,8 @@
     {
       "id": 18,
       "name": "Alah",
-      "centroid_x": 3057.6,
-      "centroid_y": 1330.3,
+      "centroid_x": 3056.0,
+      "centroid_y": 1330.0,
       "area": 35076,
       "orientation": -25.515287772906877,
       "principal_length": 285.6,
@@ -102,8 +102,8 @@
     {
       "id": 34,
       "name": "Turton",
-      "centroid_x": 2586.7,
-      "centroid_y": 1506.5,
+      "centroid_x": 2598.0,
+      "centroid_y": 1500.0,
       "area": 37458,
       "orientation": -89.27834794069042,
       "principal_length": 295.6,
@@ -113,8 +113,8 @@
     {
       "id": 41,
       "name": "Parnia",
-      "centroid_x": 397.9,
-      "centroid_y": 962.3,
+      "centroid_x": 398.0,
+      "centroid_y": 963.0,
       "area": 184733,
       "orientation": 80.31028460303715,
       "principal_length": 816.0,
@@ -124,8 +124,8 @@
     {
       "id": 7,
       "name": "Oryslia",
-      "centroid_x": 2494.9,
-      "centroid_y": 1104.4,
+      "centroid_x": 2476.0,
+      "centroid_y": 1058.0,
       "area": 108679,
       "orientation": 53.601133897917535,
       "principal_length": 673.2,
@@ -135,7 +135,7 @@
     {
       "id": 6,
       "name": "Soria",
-      "centroid_x": 611.2,
+      "centroid_x": 611.0,
       "centroid_y": 587.0,
       "area": 37567,
       "orientation": 73.04044050523646,
@@ -146,7 +146,7 @@
     {
       "id": 26,
       "name": "Reigia",
-      "centroid_x": 1538.6,
+      "centroid_x": 1538.0,
       "centroid_y": 824.0,
       "area": 105738,
       "orientation": -56.461232070203295,
@@ -157,8 +157,8 @@
     {
       "id": 21,
       "name": "Sigkarl",
-      "centroid_x": 1776.1,
-      "centroid_y": 688.7,
+      "centroid_x": 1776.0,
+      "centroid_y": 688.0,
       "area": 52475,
       "orientation": -80.26596706568765,
       "principal_length": 411.4,
@@ -168,8 +168,8 @@
     {
       "id": 42,
       "name": "Grytrand",
-      "centroid_x": 1064.1,
-      "centroid_y": 369.5,
+      "centroid_x": 1056.0,
+      "centroid_y": 373.0,
       "area": 37511,
       "orientation": 61.866124085696136,
       "principal_length": 315.1,
@@ -179,8 +179,8 @@
     {
       "id": 13,
       "name": "Al Raala",
-      "centroid_x": 3164.8,
-      "centroid_y": 1142.9,
+      "centroid_x": 3165.0,
+      "centroid_y": 1142.0,
       "area": 64624,
       "orientation": 1.6109698686653782,
       "principal_length": 417.0,
@@ -190,8 +190,8 @@
     {
       "id": 3,
       "name": "Laufarvia",
-      "centroid_x": 770.1,
-      "centroid_y": 437.8,
+      "centroid_x": 770.0,
+      "centroid_y": 437.0,
       "area": 37521,
       "orientation": -42.64914861683819,
       "principal_length": 253.6,
@@ -201,7 +201,7 @@
     {
       "id": 8,
       "name": "Atfordia",
-      "centroid_x": 2473.6,
+      "centroid_x": 2474.0,
       "centroid_y": 527.0,
       "area": 78637,
       "orientation": -15.123132625107454,
@@ -212,8 +212,8 @@
     {
       "id": 33,
       "name": "Usvol",
-      "centroid_x": 939.2,
-      "centroid_y": 417.9,
+      "centroid_x": 939.0,
+      "centroid_y": 418.0,
       "area": 37617,
       "orientation": 72.87731176765703,
       "principal_length": 329.4,
@@ -223,8 +223,8 @@
     {
       "id": 9,
       "name": "Bolve",
-      "centroid_x": 1554.3,
-      "centroid_y": 567.8,
+      "centroid_x": 1554.0,
+      "centroid_y": 568.0,
       "area": 37519,
       "orientation": -28.254514479055615,
       "principal_length": 297.1,
@@ -234,8 +234,8 @@
     {
       "id": 17,
       "name": "Hofolen",
-      "centroid_x": 1193.4,
-      "centroid_y": 496.5,
+      "centroid_x": 1192.0,
+      "centroid_y": 497.0,
       "area": 37530,
       "orientation": -40.73421792639953,
       "principal_length": 321.3,
@@ -245,8 +245,8 @@
     {
       "id": 15,
       "name": "Pieksa",
-      "centroid_x": 3373.6,
-      "centroid_y": 752.0,
+      "centroid_x": 3372.0,
+      "centroid_y": 753.0,
       "area": 37474,
       "orientation": -42.30480488812397,
       "principal_length": 302.7,
@@ -256,8 +256,8 @@
     {
       "id": 1,
       "name": "Shumal",
-      "centroid_x": 2841.2,
-      "centroid_y": 1426.4,
+      "centroid_x": 2841.0,
+      "centroid_y": 1426.0,
       "area": 35197,
       "orientation": -26.08271079122629,
       "principal_length": 286.9,
@@ -267,8 +267,8 @@
     {
       "id": 5,
       "name": "Musland",
-      "centroid_x": 2776.1,
-      "centroid_y": 685.8,
+      "centroid_x": 2776.0,
+      "centroid_y": 686.0,
       "area": 88353,
       "orientation": -67.33176588364896,
       "principal_length": 410.3,
@@ -278,8 +278,8 @@
     {
       "id": 19,
       "name": "Hella",
-      "centroid_x": 809.4,
-      "centroid_y": 600.1,
+      "centroid_x": 810.0,
+      "centroid_y": 600.0,
       "area": 37632,
       "orientation": -29.964829271657674,
       "principal_length": 292.4,
@@ -289,7 +289,7 @@
     {
       "id": 24,
       "name": "Tatoros",
-      "centroid_x": 2452.8,
+      "centroid_x": 2453.0,
       "centroid_y": 1508.0,
       "area": 37547,
       "orientation": 64.24404335610743,
@@ -300,8 +300,8 @@
     {
       "id": 10,
       "name": "Vovimaria",
-      "centroid_x": 608.9,
-      "centroid_y": 818.4,
+      "centroid_x": 613.0,
+      "centroid_y": 807.0,
       "area": 37474,
       "orientation": 42.325246247463234,
       "principal_length": 451.9,
@@ -311,8 +311,8 @@
     {
       "id": 14,
       "name": "Onmaa",
-      "centroid_x": 3464.3,
-      "centroid_y": 864.9,
+      "centroid_x": 3465.0,
+      "centroid_y": 876.0,
       "area": 48302,
       "orientation": -33.08899725807026,
       "principal_length": 465.4,
@@ -323,7 +323,7 @@
       "id": 32,
       "name": "Ingia",
       "centroid_x": 445.0,
-      "centroid_y": 614.2,
+      "centroid_y": 615.0,
       "area": 37475,
       "orientation": 40.330942997303495,
       "principal_length": 270.3,
@@ -333,8 +333,8 @@
     {
       "id": 11,
       "name": "Garholtia",
-      "centroid_x": 768.3,
-      "centroid_y": 805.8,
+      "centroid_x": 768.0,
+      "centroid_y": 807.0,
       "area": 37509,
       "orientation": 73.25523522382795,
       "principal_length": 275.4,
@@ -344,8 +344,8 @@
     {
       "id": 2,
       "name": "Motcia",
-      "centroid_x": 2989.1,
-      "centroid_y": 672.1,
+      "centroid_x": 2989.0,
+      "centroid_y": 674.0,
       "area": 37541,
       "orientation": 71.01019565314077,
       "principal_length": 340.1,
@@ -355,8 +355,8 @@
     {
       "id": 20,
       "name": "Elekes",
-      "centroid_x": 2354.4,
-      "centroid_y": 1346.4,
+      "centroid_x": 2355.0,
+      "centroid_y": 1346.0,
       "area": 37570,
       "orientation": -4.693928802826447,
       "principal_length": 300.8,
@@ -366,8 +366,8 @@
     {
       "id": 16,
       "name": "Oscasland",
-      "centroid_x": 2033.5,
-      "centroid_y": 740.9,
+      "centroid_x": 2033.0,
+      "centroid_y": 741.0,
       "area": 92595,
       "orientation": -7.875650568974214,
       "principal_length": 519.3,
@@ -377,8 +377,8 @@
     {
       "id": 30,
       "name": "Tegrot",
-      "centroid_x": 1736.5,
-      "centroid_y": 1018.5,
+      "centroid_x": 1736.0,
+      "centroid_y": 1018.0,
       "area": 122426,
       "orientation": -20.247381662688625,
       "principal_length": 568.2,
@@ -388,8 +388,8 @@
     {
       "id": 40,
       "name": "Faluria",
-      "centroid_x": 976.7,
-      "centroid_y": 744.3,
+      "centroid_x": 976.0,
+      "centroid_y": 746.0,
       "area": 80344,
       "orientation": -62.2520755175581,
       "principal_length": 494.3,
@@ -399,8 +399,8 @@
     {
       "id": 25,
       "name": "Fluria",
-      "centroid_x": 1245.7,
-      "centroid_y": 835.6,
+      "centroid_x": 1245.0,
+      "centroid_y": 836.0,
       "area": 155157,
       "orientation": -66.31259041323624,
       "principal_length": 561.7,
@@ -410,8 +410,8 @@
     {
       "id": 35,
       "name": "Tumala",
-      "centroid_x": 3211.2,
-      "centroid_y": 1409.8,
+      "centroid_x": 3210.0,
+      "centroid_y": 1409.0,
       "area": 25474,
       "orientation": 33.16003147165417,
       "principal_length": 283.2,
@@ -421,8 +421,8 @@
     {
       "id": 31,
       "name": "Nikemi",
-      "centroid_x": 3200.5,
-      "centroid_y": 882.0,
+      "centroid_x": 3200.0,
+      "centroid_y": 881.0,
       "area": 40737,
       "orientation": 57.09128390939083,
       "principal_length": 378.6,
@@ -432,8 +432,8 @@
     {
       "id": 22,
       "name": "Chipingia",
-      "centroid_x": 2206.4,
-      "centroid_y": 580.2,
+      "centroid_x": 2209.0,
+      "centroid_y": 588.0,
       "area": 40656,
       "orientation": -48.11179717863961,
       "principal_length": 286.5,
@@ -443,8 +443,8 @@
     {
       "id": 23,
       "name": "Eivikia",
-      "centroid_x": 1359.5,
-      "centroid_y": 506.6,
+      "centroid_x": 1360.0,
+      "centroid_y": 506.0,
       "area": 37555,
       "orientation": -49.357592556477876,
       "principal_length": 285.3,
@@ -454,8 +454,8 @@
     {
       "id": 38,
       "name": "Wichel",
-      "centroid_x": 2399.6,
-      "centroid_y": 792.4,
+      "centroid_x": 2395.0,
+      "centroid_y": 781.0,
       "area": 122281,
       "orientation": -26.154786547398853,
       "principal_length": 627.0,
@@ -465,8 +465,8 @@
     {
       "id": 12,
       "name": "Pozia",
-      "centroid_x": 2950.6,
-      "centroid_y": 338.6,
+      "centroid_x": 2960.0,
+      "centroid_y": 395.0,
       "area": 56289,
       "orientation": -65.77001402153415,
       "principal_length": 522.5,
@@ -474,4 +474,4 @@
       "curvature": -9.3
     }
   ]
-}
+}

tools/map_generator/generate_map.py

@@ -9,6 +9,7 @@ Usage:
     python generate_map.py --analyze          # Analyze current map, show province sizes
     python generate_map.py --generate         # Generate new equalized map
     python generate_map.py --visualize        # Generate visualization of current vs new
+    python generate_map.py --update-centroids # Update label positions in centroids.json
 """
 
 import argparse
@@ -89,6 +90,39 @@ def load_province_data() -> dict[int, dict]:
     return provinces
 
 
+def find_label_position(mask: np.ndarray) -> tuple[float, float]:
+    """Find the best label position for a province.
+
+    Finds all pixels with at least 70% of the province's maximum possible
+    clearance from edges, then picks the one closest to the geometric centroid.
+    This guarantees good distance from borders/coastlines while keeping labels
+    as visually centered as possible.
+
+    Returns (x, y) in pixel coordinates.
+    """
+    # Geometric centroid (visual center of mass)
+    y_coords, x_coords = np.where(mask)
+    mean_x = np.mean(x_coords)
+    mean_y = np.mean(y_coords)
+
+    # Distance from nearest edge for every province pixel
+    dist = ndimage.distance_transform_edt(mask)
+    max_clearance = np.max(dist)
+
+    # Require at least 70% of the best possible clearance
+    candidates = dist >= max_clearance * 0.7
+
+    if np.any(candidates):
+        cand_ys, cand_xs = np.where(candidates)
+        dists_to_centroid = (cand_xs - mean_x)**2 + (cand_ys - mean_y)**2
+        best = np.argmin(dists_to_centroid)
+        return float(cand_xs[best]), float(cand_ys[best])
+
+    # Fallback: pole of inaccessibility
+    max_idx = np.unravel_index(np.argmax(dist), dist.shape)
+    return float(max_idx[1]), float(max_idx[0])
+
+
 def analyze_provinces(raw_gray: np.ndarray, province_data: dict) -> list[Province]:
     """Calculate centroid and area for each province."""
     provinces = []
@@ -102,10 +136,7 @@ def analyze_provinces(raw_gray: np.ndarray, province_data: dict) -> list[Provinc
             print(f"Warning: Province {province_id} ({data['name']}) has no pixels")
             continue
 
-        # Calculate centroid (center of mass)
-        y_coords, x_coords = np.where(mask)
-        centroid_x = np.mean(x_coords)
-        centroid_y = np.mean(y_coords)
+        centroid_x, centroid_y = find_label_position(mask)
 
         provinces.append(Province(
             id=province_id,
@@ -530,26 +561,85 @@ def generate_visualization(
 
 
 def save_centroids(provinces: list[Province], output_path: Path):
-    """Save province centroids to JSON for Unity label positioning."""
-    data = {
-        "provinces": [
-            {
-                "id": int(p.id),
-                "name": p.name,
-                "centroid_x": float(p.centroid[0]),
-                "centroid_y": float(p.centroid[1]),
-                "area": int(p.area)
-            }
-            for p in provinces
-        ]
-    }
+    """Save province centroids to JSON for Unity label positioning.
+
+    Preserves hand-tuned fields (orientation, principal_length, etc.)
+    from existing centroids.json if present.
+    """
+    # Load existing data to preserve hand-tuned fields
+    existing_by_id = {}
+    for candidate in [output_path, UNITY_ASSETS / "centroids.json"]:
+        if candidate.exists():
+            with open(candidate, 'r') as f:
+                existing_by_id = {p['id']: p for p in json.load(f)['provinces']}
+            break
+
+    province_list = []
+    for p in provinces:
+        entry = {
+            "id": int(p.id),
+            "name": p.name,
+            "centroid_x": round(float(p.centroid[0]), 1),
+            "centroid_y": round(float(p.centroid[1]), 1),
+            "area": int(p.area)
+        }
+        # Preserve hand-tuned fields from existing file
+        if p.id in existing_by_id:
+            for field in ("orientation", "principal_length", "perpendicular_width", "curvature"):
+                if field in existing_by_id[p.id]:
+                    entry[field] = existing_by_id[p.id][field]
+        province_list.append(entry)
+
+    data = {"provinces": province_list}
 
     with open(output_path, 'w') as f:
         json.dump(data, f, indent=2)
+        f.write('\n')
 
     print(f"Saved centroids to {output_path}")
 
 
+def update_centroids(raw_gray: np.ndarray, province_data: dict):
+    """Update centroids.json with pole-of-inaccessibility positions.
+
+    Only updates centroid_x and centroid_y, preserving all hand-tuned fields
+    (orientation, principal_length, perpendicular_width, curvature).
+    """
+    centroids_path = UNITY_ASSETS / "centroids.json"
+
+    with open(centroids_path, 'r') as f:
+        data = json.load(f)
+
+    existing_by_id = {p['id']: p for p in data['provinces']}
+
+    updated = 0
+    for province_id, pdata in province_data.items():
+        mask = raw_gray == province_id
+        area = np.sum(mask)
+        if area == 0:
+            print(f"Warning: Province {province_id} ({pdata['name']}) has no pixels")
+            continue
+
+        lx, ly = find_label_position(mask)
+        new_x = round(lx, 1)
+        new_y = round(ly, 1)
+
+        if province_id in existing_by_id:
+            entry = existing_by_id[province_id]
+            old_x, old_y = entry['centroid_x'], entry['centroid_y']
+            if old_x != new_x or old_y != new_y:
+                print(f"  {pdata['name']:20s}: ({old_x}, {old_y}) -> ({new_x}, {new_y})")
+                entry['centroid_x'] = new_x
+                entry['centroid_y'] = new_y
+                updated += 1
+
+    with open(centroids_path, 'w') as f:
+        json.dump(data, f, indent=2)
+        f.write('\n')
+
+    print(f"Updated {updated} centroids in {centroids_path}")
+
+
 def save_raw_gray(province_map: np.ndarray, output_path: Path, compress: bool = True):
     """Save province map as raw bytes (optionally gzip compressed)."""
     # Flip for Unity (bottom-left origin)
@@ -572,6 +662,8 @@ def main():
     parser.add_argument('--analyze', action='store_true', help='Analyze current map')
     parser.add_argument('--generate', action='store_true', help='Generate new equalized map')
     parser.add_argument('--visualize', action='store_true', help='Generate visualization')
+    parser.add_argument('--update-centroids', action='store_true',
+                       help='Update centroid positions in centroids.json (preserves hand-tuned fields)')
     parser.add_argument('--target-ratio', type=float, default=0.5,
                        help='Target minimum province size as ratio of average (default: 0.5)')
     parser.add_argument('--output-dir', type=Path, default=SCRIPT_DIR / 'output',
@@ -579,7 +671,7 @@ def main():
 
     args = parser.parse_args()
 
-    if not any([args.analyze, args.generate, args.visualize]):
+    if not any([args.analyze, args.generate, args.visualize, args.update_centroids]):
         args.analyze = True  # Default to analyze
 
     print("Loading province data...")
@@ -590,6 +682,11 @@ def main():
     raw_gray = load_raw_gray()
     print(f"Map dimensions: {raw_gray.shape[1]} x {raw_gray.shape[0]}")
 
+    if args.update_centroids:
+        print("Updating centroids with pole-of-inaccessibility positions...")
+        update_centroids(raw_gray, province_data)
+        return
+
     print("Analyzing provinces...")
     provinces = analyze_provinces(raw_gray, province_data)