diff --git a/src/db/db/dbEdges.cc b/src/db/db/dbEdges.cc
index 5c41840c6..9d2fa8d39 100644
--- a/src/db/db/dbEdges.cc
+++ b/src/db/db/dbEdges.cc
@@ -724,7 +724,6 @@ Edges::select_interacting (const Region &other)
     scanner.insert ((char *) &*e, 0);
   }
 
-  other.ensure_valid_polygons ();
   for (Region::const_iterator p = other.begin (); ! p.at_end (); ++p) {
     scanner.insert ((char *) &*p + 1, 1);
   }
@@ -754,7 +753,6 @@ Edges::select_not_interacting (const Region &other)
     scanner.insert ((char *) &*e, 0);
   }
 
-  other.ensure_valid_polygons ();
   for (Region::const_iterator p = other.begin (); ! p.at_end (); ++p) {
     scanner.insert ((char *) &*p + 1, 1);
   }
diff --git a/src/db/db/dbEdges.h b/src/db/db/dbEdges.h
index fae01830e..3f31351dc 100644
--- a/src/db/db/dbEdges.h
+++ b/src/db/db/dbEdges.h
@@ -581,12 +581,11 @@ public:
    *  This method will keep all edges for which the filter returns true.
    *  Merged semantics applies.
    */
-  template <class F>
-  Edges &filter (F &filter)
+  Edges &filter (EdgeFilterBase &filter)
   {
     edge_iterator_type ew = m_edges.get_layer<db::Edge, db::unstable_layer_tag> ().begin ();
     for (const_iterator e = begin_merged (); ! e.at_end (); ++e) {
-      if (filter (*e)) {
+      if (filter.selected (*e)) {
         if (ew == m_edges.get_layer<db::Edge, db::unstable_layer_tag> ().end ()) {
           m_edges.get_layer<db::Edge, db::unstable_layer_tag> ().insert (*e);
           ew = m_edges.get_layer<db::Edge, db::unstable_layer_tag> ().end ();
@@ -609,12 +608,11 @@ public:
    *  conform to the filter criterion.
    *  Merged semantics applies.
    */
-  template <class F>
-  Edges filtered (F &filter) const
+  Edges filtered (const EdgeFilterBase &filter) const
   {
     Edges d;
     for (const_iterator e = begin_merged (); ! e.at_end (); ++e) {
-      if (filter (*e)) {
+      if (filter.selected (*e)) {
         d.insert (*e);
       }
     }
diff --git a/src/db/db/dbRegion.h b/src/db/db/dbRegion.h
index bd357b6b7..e640125b5 100644
--- a/src/db/db/dbRegion.h
+++ b/src/db/db/dbRegion.h
@@ -3422,6 +3422,7 @@ private:
   Region selected_interacting_generic (const Edges &other, bool inverse) const;
   void select_interacting_generic (const Edges &other, bool inverse);
 };
+#endif
 
 /**
  *  @brief A polygon receiver putting the polygons into a Region object
@@ -3466,7 +3467,6 @@ private:
   Region *mp_region;
   bool m_clear;
 };
-#endif
 
 } // namespace db
 
diff --git a/src/db/unit_tests/dbTilingProcessor.cc b/src/db/unit_tests/dbTilingProcessor.cc
index cb67d5aad..5aa0b1216 100644
--- a/src/db/unit_tests/dbTilingProcessor.cc
+++ b/src/db/unit_tests/dbTilingProcessor.cc
@@ -237,7 +237,6 @@ TEST(3)
   tp.input ("i2", ir2.begin_iter ().first, ir2.begin_iter ().second);
   EXPECT_EQ (ir2.has_valid_polygons (), false);
   db::Region ir3 (db::RecursiveShapeIterator (ly, ly.cell (top), l3));
-  ir3.ensure_valid_polygons ();
   tp.input ("i3", ir3.begin_iter ().first, ir3.begin_iter ().second);
   EXPECT_EQ (ir3.has_valid_polygons (), true);
   tp.output ("o1", ly, top, o1);