Support multiple polygons

spatial-data-lab · Jan 7, 2025 · 79ec430 · 79ec430
1 parent 8b06dd7
commit 79ec430
Showing 1 changed file with 14 additions and 7 deletions.
diff --git a/knime_extension/src/nodes/spatialtool.py b/knime_extension/src/nodes/spatialtool.py
@@ -1266,25 +1266,32 @@ def configure(self, configure_context, input_schema):
 
     def execute(self, exec_context: knext.ExecutionContext, input_table):
         import h3
-        from shapely.geometry import Polygon
+        from shapely.geometry import Polygon, mapping
+        from shapely.ops import unary_union
         import geopandas as gpd
         import pandas as pd
 
         gdf_boundary = knut.load_geo_data_frame(input_table, self.geo_col, exec_context)
 
         knut.check_canceled(exec_context)
         exec_context.set_progress(0.1, "Projecting input polygon...")
-        gdf_boundary.to_crs(4326, inplace=True)
+        USE_CRS = 4326
+        gdf_boundary.to_crs(USE_CRS, inplace=True)
 
         knut.check_canceled(exec_context)
         exec_context.set_progress(0.3, "Combining input polygon...")
-        gdf_boundary["geometry"] = gdf_boundary.unary_union
+        gdf_boundary = unary_union(gdf_boundary[self.geo_col])
+        gdf_boundary = gpd.GeoDataFrame(geometry=[gdf_boundary], crs=USE_CRS)
+
+        knut.check_canceled(exec_context)
+        exec_context.set_progress(0.4, "Exploding input polygon...")
+        gdf_boundary = gdf_boundary.explode(index_parts=True)
+        gdf_boundary.reset_index(drop=True, inplace=True)
 
         knut.check_canceled(exec_context)
         exec_context.set_progress(0.5, "Computing H3 hexagons...")
-        h3_hexes = h3.polyfill_geojson(
-            gdf_boundary.geometry.__geo_interface__["features"][0]["geometry"],
-            self.zoom,
+        h3_hexes = set().union(
+            *[h3.polyfill_geojson(mapping(p), self.zoom) for p in gdf_boundary.geometry]
         )
 
         knut.check_canceled(exec_context)
@@ -1295,7 +1302,7 @@ def execute(self, exec_context: knext.ExecutionContext, input_table):
                 Polygon(h3.h3_to_geo_boundary(h3_hex, geo_json=True))
                 for h3_hex in h3_hexes
             ],
-            crs=gdf_boundary.crs,
+            crs=USE_CRS,
         )
         grid.rename_geometry(self._COL_GEOMETRY, True)