bugfix in tile script and updates to the params for get_4way_intersection_point

Author: ramSeraph

README.md

@@ -135,7 +135,13 @@ The `get_intersection_point` method is the most critical part to customize for a
     3.  Identifying the point closest to the expected corner position, while also matching an expected angle and distance from an anchor point.
 
 ![corner for 4way intersection point](/samples/corner3.png)
--   **`get_4way_intersection_point`**: This is a more robust version for crosshair-style corners. It specifically looks for intersections where four lines meet, making it less prone to errors from stray lines in the map collar.
+-   **`get_4way_intersection_point`**: This is a more robust version for crosshair-style corners. It works by:
+    1.  Isolating lines based on their color.
+    2.  Optionally removing any text that might interfere with line detection.
+    3.  Ignoring the edges of the corner image patch to avoid spurious intersections with the border.
+    4.  Detecting all horizontal and vertical lines and finding their intersection points.
+    5.  Validating each intersection by checking for the presence of lines extending in all four directions (up, down, left, right) from the intersection point. This ensures it's a true 4-way "crosshair" intersection.
+    6.  It is designed to be very specific and will fail if it doesn't find exactly one 4-way intersection.
 
 ![corner for biggest contour corner](/samples/corner2.png)
 -   **`get_biggest_contour_corner`**: This strategy is designed for corners that are marked by a solid shape or a filled area (e.g., a colored square or circle). It works by:

topo_map_processor/processor.py

@@ -1074,12 +1074,16 @@ def get_nearest_intersection_point(self, img,
 
         return ip
 
-    def get_4way_intersection_point(self, img, line_color, 
+    def get_4way_intersection_point(self, img, line_color, remove_text,
                                     find_line_scale, find_line_iter, 
-                                    cwidth, ext_thresh):
+                                    cwidth, ext_thresh, direction,
+                                    remove_corner_edges_ratio):
         img_mask = self.get_color_mask(img, line_color)
 
-        self.remove_text(img_mask)
+        if remove_text:
+            self.remove_text(img_mask)
+
+        self.remove_corner_edges(img_mask, direction, remove_corner_edges_ratio)
 
         h, w = img_mask.shape[:2]
         self.show_image(img_mask)
@@ -1106,7 +1110,8 @@ def get_4way_intersection_point(self, img, line_color,
             if len(four_corner_ips) > 1:
                 continue
 
-            self.show_points(four_corner_ips, img_mask, [0, 255, 0])
+        self.show_points(four_corner_ips, img_mask, [0, 255, 0])
+
         if len(four_corner_ips) > 1:
             raise Exception(f'multiple intersection points found - {len(four_corner_ips)}')
 

topo_map_processor/tools/tile.py

@@ -9,6 +9,7 @@
 
 from pathlib import Path
 from multiprocessing import set_start_method, cpu_count
+from pprint import pprint
 
 from osgeo_utils.gdal2tiles import submain as gdal2tiles_main
 
@@ -56,6 +57,14 @@ def get_tiler_cmd_params(tile_extension, tile_quality):
 
     raise ValueError(f'Unsupported tile extension: {tile_extension}, {SUPPORTED_FORMATS=}')
 
+def get_format(tile_extension):
+    if tile_extension == 'webp':
+        return 'webp'
+    if tile_extension == 'jpeg':
+        return 'jpeg'
+    if tile_extension == 'png':
+        return 'png'
+    raise ValueError(f'Unsupported tile extension: {tile_extension}, {SUPPORTED_FORMATS=}')
 
 
 def cli():
@@ -131,17 +140,22 @@ def cli():
 
     metadata_file = tiles_dir / 'tiles.json'
 
+    fmt = get_format(args.tile_extension)
+
     # it is not really a proper tilejson spec.. it is the basic things needed to populate a pmtiles metadata
     metadata = {
         'type': 'baselayer',
-        'format': format,
+        'format': fmt,
         'attribution': attribution_text,
         'description': args.description,
         'name': args.name,
         'version': '1',
         'maxzoom': args.max_zoom,
         'minzoom': args.min_zoom,
     }
+
+    print(f'writing metadata to {metadata_file}')
+    pprint(metadata)
     metadata_file.write_text(json.dumps(metadata, indent=2))
 
     print('All Done!!')