Fixing bug in first place. Needs testing.

src/db/db/dbFillTool.cc

@@ -77,14 +77,14 @@ public:
     }
 
     //  because the rasterizer can't handle overlapping cells we need to multiply the row and columns steps
-    //  with an integer until the effective rasterizer pitch get big enough.
+    //  with an integer until the effective rasterizer pitch gets big enough.
     m_row_steps *= (m_dim.x () - 1) / (m_row_steps * m_row_step.x ()) + 1;
     m_column_steps *= (m_dim.y () - 1) / (m_column_steps * m_column_step.y ()) + 1;
 
     db::Box fp_bbox = fp.box ();
 
     //  compensate for distortion by sheared kernel
-    fp_bbox.enlarge (db::Vector (db::coord_traits<db::Coord>::rounded (double (fp_bbox.height ()) * std::abs (m_column_step.x ()) / dy), db::coord_traits<db::Coord>::rounded (double (fp_bbox.width ()) * std::abs (m_row_step.y ()) / dx)));
+    fp_bbox.enlarge (db::Vector (m_column_step.x () * m_column_steps, m_row_step.y () * m_row_steps));
 
     int columns_per_rows = (int (m_row_steps) * m_row_step.y ()) / dy;
     int rows_per_columns = (int (m_column_steps) * m_column_step.x ()) / dx;

src/db/unit_tests/dbFillToolTests.cc

@@ -345,3 +345,35 @@ TEST(5)
   CHECKPOINT();
   db::compare_layouts (_this, ly, tl::testdata () + "/algo/fill_tool_au5.oas", db::WriteOAS);
 }
+
+//  issue #2087
+TEST(6)
+{
+  db::Layout ly;
+  {
+    std::string fn (tl::testdata ());
+    fn += "/algo/fill_tool6.gds";
+    tl::InputStream stream (fn);
+    db::Reader reader (stream);
+    reader.read (ly);
+  }
+
+  db::cell_index_type fill_cell = ly.cell_by_name ("FILL_CELL").second;
+  db::cell_index_type top_cell = ly.cell_by_name ("TOP").second;
+  unsigned int fill_layer = ly.get_layer (db::LayerProperties (1, 0));
+
+  db::Region fill_region (db::RecursiveShapeIterator (ly, ly.cell (top_cell), fill_layer));
+
+  db::Region remaining_polygons;
+
+  db::Vector rs (2500, 0);
+  db::Vector cs (650, 2500);
+  db::Box fc_box = ly.cell (fill_cell).bbox ();
+  db::fill_region (&ly.cell (top_cell), fill_region, fill_cell, fc_box, rs, cs, db::Point (), false, &remaining_polygons);
+
+  unsigned int l100 = ly.insert_layer (db::LayerProperties (100, 0));
+  remaining_polygons.insert_into (&ly, top_cell, l100);
+
+  CHECKPOINT();
+  db::compare_layouts (_this, ly, tl::testdata () + "/algo/fill_tool_au6.oas", db::WriteOAS);
+}