WIP - experimental feature to resolve sparse cell arrays

src/db/db/dbHierarchyBuilder.cc

@@ -396,13 +396,52 @@ HierarchyBuilder::new_inst (const RecursiveShapeIterator *iter, const db::CellIn
 
     //  for new cells, create this instance
     if (m_cell_stack.back ().first || m_cm_new_entry) {
-      db::CellInstArray new_inst (inst, &mp_target->array_repository ());
-      new_inst.object () = db::CellInst (new_cell);
-      new_inst.transform (always_apply);
-      new_inst.transform_into (m_trans);
-      for (std::vector<db::Cell *>::const_iterator c = m_cell_stack.back ().second.begin (); c != m_cell_stack.back ().second.end (); ++c) {
-        (*c)->insert (new_inst);
+
+      // @@@
+      //  check if the cell array is "sparse"
+      bool resolve = false;
+      if (m_source.layout () && inst.size () > 1) {
+        db::box_convert<db::CellInst> bc (*m_source.layout ());
+        auto a1 = bc (inst.object ()).area ();
+        auto aa = inst.bbox (bc).area ();
+        double area_ratio = 10.0; // @@@
+        if (a1 * area_ratio < aa) {
+          resolve = true;
+        }
       }
+      // @@@
+
+      if (resolve) {
+
+        //  resolve the instances of the array
+        for (auto i = inst.begin (); !i.at_end (); ++i) {
+
+          db::CellInstArray new_inst;
+          if (inst.is_complex ()) {
+            new_inst = db::CellInstArray (db::CellInst (new_cell), inst.complex_trans (*i));
+          } else {
+            new_inst = db::CellInstArray (db::CellInst (new_cell), *i);
+          }
+          new_inst.transform (always_apply);
+          new_inst.transform_into (m_trans);
+          for (std::vector<db::Cell *>::const_iterator c = m_cell_stack.back ().second.begin (); c != m_cell_stack.back ().second.end (); ++c) {
+            (*c)->insert (new_inst);
+          }
+
+        }
+
+      } else {
+
+        db::CellInstArray new_inst (inst, &mp_target->array_repository ());
+        new_inst.object () = db::CellInst (new_cell);
+        new_inst.transform (always_apply);
+        new_inst.transform_into (m_trans);
+        for (std::vector<db::Cell *>::const_iterator c = m_cell_stack.back ().second.begin (); c != m_cell_stack.back ().second.end (); ++c) {
+          (*c)->insert (new_inst);
+        }
+
+      }
+
     }
 
     //  To see the cell once, use NI_single. If we did see the cell already, skip the whole instance array.

src/db/db/gsiDeclDbDeepShapeStore.cc

@@ -259,6 +259,9 @@ Class<db::DeepShapeStore> decl_dbDeepShapeStore ("db", "DeepShapeStore",
     "\n"
     "This method has been added in version 0.26.1\n"
   ) +
+  gsi::method ("layout", static_cast<db::Layout &(db::DeepShapeStore::*) (unsigned int)> (&db::DeepShapeStore::layout), gsi::arg ("index"),
+    "@hide"
+  ) +
   gsi::method ("push_state", &db::DeepShapeStore::push_state,
     "@brief Pushes the store's state on the state state\n"
     "This will save the stores state (\\threads, \\max_vertex_count, \\max_area_ratio, breakout cells ...) on "