From b9588627f04d47319b6dd424d3a9d49d4fbfeff2 Mon Sep 17 00:00:00 2001
From: Joachim Schoeberl <joachim.schoeberl@tuwien.ac.at>
Date: Mon, 30 Aug 2021 22:00:58 +0200
Subject: [PATCH] use history in OCCT - fuse

---
 libsrc/csg/csgeom.cpp            |  4 ++--
 libsrc/occ/python_occ_shapes.cpp | 19 ++++++++++++++++++-
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/libsrc/csg/csgeom.cpp b/libsrc/csg/csgeom.cpp
index e1ada634..c1256a19 100644
--- a/libsrc/csg/csgeom.cpp
+++ b/libsrc/csg/csgeom.cpp
@@ -312,7 +312,7 @@ namespace netgen
   {
     //  CSGeometry * geo = new CSGeometry;
   
-    char key[100], name[100], classname[100], sname[100];
+    char key[100], name[100], classname[100], sname[150];
     int ncoeff, i, j;
     NgArray<double> coeff;
 
@@ -622,7 +622,7 @@ namespace netgen
   {
     static int cntsurfs = 0;
     cntsurfs++;
-    char name[15];
+    char name[20];
     sprintf (name, "nnsurf%d", cntsurfs);
     AddSurface (name, surf);
   }
diff --git a/libsrc/occ/python_occ_shapes.cpp b/libsrc/occ/python_occ_shapes.cpp
index 3f55f8a5..13ad6509 100644
--- a/libsrc/occ/python_occ_shapes.cpp
+++ b/libsrc/occ/python_occ_shapes.cpp
@@ -540,6 +540,7 @@ public:
     BRepBuilderAPI_MakeFace builder(surf, 1e-8);
     for (auto w : wires)
       builder.Add(w);
+    wires.clear();
     return builder.Face();
   }
 
@@ -746,8 +747,24 @@ DLL_HEADER void ExportNgOCCShapes(py::module &m)
                   { return shape.Located(loc); })
 
     .def("__add__", [] (const TopoDS_Shape & shape1, const TopoDS_Shape & shape2) {
-        auto fused = BRepAlgoAPI_Fuse(shape1, shape2).Shape();
+        // auto fused = BRepAlgoAPI_Fuse(shape1, shape2).Shape();
         // return fused;
+
+        BRepAlgoAPI_Fuse builder(shape1, shape2);
+#ifdef OCC_HAVE_HISTORY
+        Handle(BRepTools_History) history = builder.History ();
+        
+        for (auto typ : { TopAbs_SOLID, TopAbs_FACE,  TopAbs_EDGE })
+          for (auto & s : { shape1, shape2 })
+            for (TopExp_Explorer e(s, typ); e.More(); e.Next())
+              {
+                auto prop = OCCGeometry::global_shape_properties[e.Current().TShape()];
+                for (auto mods : history->Modified(e.Current()))
+                  OCCGeometry::global_shape_properties[mods.TShape()].Merge(prop);
+              }
+#endif        
+        auto fused = builder.Shape();        
+
         
         // make one face when fusing in 2D
         // from https://gitlab.onelab.info/gmsh/gmsh/-/issues/627