Merge pull request #3345 from lonvia/simplify-large-geometries

Simplify very large polygons that are not used in addresses

lib-sql/functions/place_triggers.sql

@@ -296,7 +296,9 @@ BEGIN
           extratags = NEW.extratags,
           admin_level = NEW.admin_level,
           indexed_status = 2,
-          geometry = NEW.geometry
+          geometry = CASE WHEN existingplacex.rank_address = 0
+                          THEN simplify_large_polygons(NEW.geometry)
+                          ELSE NEW.geometry END
       WHERE place_id = existingplacex.place_id;
 
     -- Invalidate linked places: they potentially get a new name and addresses.

lib-sql/functions/placex_triggers.sql

@@ -718,6 +718,12 @@ BEGIN
       NEW.country_code := NULL;
     END IF;
 
+    -- Simplify polygons with a very large memory footprint when they
+    -- do not take part in address computation.
+    IF NEW.rank_address = 0 THEN
+      NEW.geometry := simplify_large_polygons(NEW.geometry);
+    END IF;
+
   END IF;
 
   {% if debug %}RAISE WARNING 'placex_insert:END: % % % %',NEW.osm_type,NEW.osm_id,NEW.class,NEW.type;{% endif %}

lib-sql/functions/utils.sql

@@ -436,6 +436,20 @@ END;
 $$
 LANGUAGE plpgsql IMMUTABLE;
 
+CREATE OR REPLACE FUNCTION simplify_large_polygons(geometry GEOMETRY)
+  RETURNS GEOMETRY
+  AS $$
+BEGIN
+  IF ST_GeometryType(geometry) in ('ST_Polygon','ST_MultiPolygon')
+     and ST_MemSize(geometry) > 3000000
+  THEN
+    geometry := ST_SimplifyPreserveTopology(geometry, 0.0001);
+  END IF;
+  RETURN geometry;
+END;
+$$
+LANGUAGE plpgsql IMMUTABLE;
+
 
 CREATE OR REPLACE FUNCTION place_force_delete(placeid BIGINT)
   RETURNS BOOLEAN