Introducing fallback transformation variants for empty layer lists. This allows editing layouts without any layers and only instances.

src/laybasic/laybasic/layFinder.cc

@@ -735,7 +735,7 @@ InstFinder::find (lay::LayoutViewBase *view, const db::DBox &region_mu)
   progress.set_format ("");
   mp_progress = &progress;
 
-  std::set< std::pair<db::DCplxTrans, int> > variants = view->cv_transform_variants ();
+  std::set< std::pair<db::DCplxTrans, int> > variants = view->cv_transform_variants_with_empty ();
   for (std::set< std::pair<db::DCplxTrans, int> >::const_iterator v = variants.begin (); v != variants.end (); ++v) {
     find (view, v->second, v->first, region_mu);
   }

src/laybasic/laybasic/layLayoutViewBase.cc

@@ -3864,8 +3864,13 @@ LayoutViewBase::full_box () const
 
   db::DBox bbox;
 
-  for (LayerPropertiesConstIterator l = get_properties ().begin_const_recursive (); ! l.at_end (); ++l) {
-    bbox += l->overall_bbox ();
+  auto tv = cv_transform_variants_with_empty ();
+  for (auto i = tv.begin (); i != tv.end (); ++i) {
+    const lay::CellView &cv = cellview (i->second);
+    if (cv.is_valid ()) {
+      double dbu = cv->layout ().dbu ();
+      bbox += (i->first * db::CplxTrans (dbu) * cv.context_trans ()) * cv.cell ()->bbox_with_empty ();
+    }
   }
 
   for (lay::AnnotationShapes::iterator a = annotation_shapes ().begin (); ! a.at_end (); ++a) {
@@ -5986,6 +5991,16 @@ LayoutViewBase::cv_transform_variants (int cv_index) const
   return std::vector<db::DCplxTrans> (trns_variants.begin (), trns_variants.end ());
 }
 
+std::vector<db::DCplxTrans>
+LayoutViewBase::cv_transform_variants_with_empty (int cv_index) const
+{
+  std::vector<db::DCplxTrans> trns_variants = cv_transform_variants (cv_index);
+  if (trns_variants.empty ()) {
+    trns_variants.push_back (db::DCplxTrans ());
+  }
+  return trns_variants;
+}
+
 std::vector<db::DCplxTrans>
 LayoutViewBase::cv_transform_variants (int cv_index, unsigned int layer) const
 {
@@ -6046,7 +6061,30 @@ LayoutViewBase::cv_transform_variants () const
   return box_variants;
 }
 
-db::InstElement 
+std::set< std::pair<db::DCplxTrans, int> >
+LayoutViewBase::cv_transform_variants_with_empty () const
+{
+  std::set< std::pair<db::DCplxTrans, int> > box_variants = cv_transform_variants ();
+
+  //  add a default box variant for the CVs not present in the layer list to
+  //  draw boxes at least.
+
+  std::vector<bool> cv_present;
+  cv_present.resize (m_cellviews.size ());
+  for (auto bv = box_variants.begin (); bv != box_variants.end (); ++bv) {
+    if (bv->second >= 0 && bv->second < int (cv_present.size ())) {
+      cv_present[bv->second] = true;
+    }
+  }
+
+  for (auto i = cv_present.begin (); i != cv_present.end (); ++i) {
+    box_variants.insert (std::make_pair (db::DCplxTrans (), int (i - cv_present.begin ())));
+  }
+
+  return box_variants;
+}
+
+db::InstElement
 LayoutViewBase::ascend (int index)
 {
   tl_assert (int (m_cellviews.size ()) > index && cellview_iter (index)->is_valid ());

src/laybasic/laybasic/layLayoutViewBase.h

@@ -1674,11 +1674,27 @@ public:
    */
   std::set< std::pair<db::DCplxTrans, int> > cv_transform_variants () const;
   
+  /**
+   *  @brief Get a list of cellview index and transform variants including empty cellviews
+   *
+   *  This version delivers a unit-transformation variant for cell views for which
+   *  no layer is present. This version is used for instance box drawing.
+   */
+  std::set< std::pair<db::DCplxTrans, int> > cv_transform_variants_with_empty () const;
+
   /**
    *  @brief Get the global transform variants for a given cellview index
    */
   std::vector<db::DCplxTrans> cv_transform_variants (int cv_index) const;
 
+  /**
+   *  @brief Get the global transform variants for a given cellview index including empty cellviews
+   *
+   *  This version delivers a unit-transformation variant for cell views for which
+   *  no layer is present. This version is used for instance box drawing.
+   */
+  std::vector<db::DCplxTrans> cv_transform_variants_with_empty (int cv_index) const;
+
   /**
    *  @brief Get the global transform variants for a given cellview index and layer
    */

src/laybasic/laybasic/layRedrawThreadWorker.cc

@@ -575,7 +575,7 @@ RedrawThreadWorker::setup (LayoutViewBase *view, RedrawThreadCanvas *canvas, con
 
   m_nlayers = mp_redraw_thread->num_layers (); 
 
-  m_box_variants = view->cv_transform_variants ();
+  m_box_variants = view->cv_transform_variants_with_empty ();
 }
 
 void