From ee4f996043e752ef00c64a369929a1c5a93e0680 Mon Sep 17 00:00:00 2001
From: Maxime Gimeno <maxime.gimeno@gmail.com>
Date: Wed, 3 Jun 2020 11:24:18 +0200
Subject: [PATCH] Add a clone to the c3t3 and fix an error in the cutting plane
 orientation

---
 Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp | 12 ++++++++++--
 Polyhedron/demo/Polyhedron/Scene_c3t3_item.h   |  5 ++---
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
index 01c192db153..1595716a2c9 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
@@ -157,7 +157,7 @@ public :
     const EPICK::Plane_3& plane = qobject_cast<Scene_c3t3_item*>(this->parent())->plane();
     float shrink_factor = qobject_cast<Scene_c3t3_item*>(this->parent())->getShrinkFactor();
     QVector4D cp = cgal_plane_to_vector4d(plane);
-    getTriangleContainer(0)->setPlane(cp);
+    getTriangleContainer(0)->setPlane(-cp);
     getTriangleContainer(0)->setShrinkFactor(shrink_factor);
     // positions_poly is also used for the faces in the cut plane
     // and changes when the cut plane is moved
@@ -569,8 +569,10 @@ Scene_c3t3_item::Scene_c3t3_item(const C3t3& c3t3, bool is_surface)
   : Scene_group_item("unnamed")
   , d(new Scene_c3t3_item_priv(c3t3, this))
 {
-  d->reset_cut_plane();
   common_constructor(is_surface);
+  d->reset_cut_plane();
+  c3t3_changed();
+  changed();
 }
 
 Scene_c3t3_item::~Scene_c3t3_item()
@@ -2097,5 +2099,11 @@ void Scene_c3t3_item::newViewer(Viewer_interface *viewer)
     d->computeIntersections(viewer);
   }
 }
+
+Scene_c3t3_item* Scene_c3t3_item::clone() const
+{
+  return new Scene_c3t3_item(d->c3t3, d->is_surface);
+}
+
 #include "Scene_c3t3_item.moc"
 
diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
index 1c2e4316451..90b02e87c7b 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
@@ -101,9 +101,8 @@ public:
   {
       return Scene_item::bbox();
   }
-  Scene_c3t3_item* clone() const  Q_DECL_OVERRIDE{
-    return 0;
-  }
+
+  Scene_c3t3_item* clone() const  Q_DECL_OVERRIDE;
 
   bool load_binary(std::istream& is);