From 94a09dc4c11e8bf45b9675d098a724a6edc1236c Mon Sep 17 00:00:00 2001
From: Andreas Fabri <andreas.fabri@geometryfactory.com>
Date: Mon, 2 May 2016 16:48:56 +0200
Subject: [PATCH] At least allow to write polyhedral surfaces into .obj files

---
 .../demo/Polyhedron/Plugins/IO/OFF_io_plugin.cpp    | 13 ++++++++++---
 .../demo/Polyhedron/Scene_polyhedron_item.cpp       | 11 +++++++++++
 Polyhedron/demo/Polyhedron/Scene_polyhedron_item.h  |  1 +
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/Polyhedron/demo/Polyhedron/Plugins/IO/OFF_io_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/IO/OFF_io_plugin.cpp
index d2aa7b6a28c..259a3dbf415 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/IO/OFF_io_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/IO/OFF_io_plugin.cpp
@@ -155,9 +155,16 @@ bool Polyhedron_demo_off_plugin::save(const CGAL::Three::Scene_item* item, QFile
 
   std::ofstream out(fileinfo.filePath().toUtf8());
   out.precision (std::numeric_limits<double>::digits10 + 2);
-  return (poly_item && poly_item->save(out)) || 
-    (soup_item && soup_item->save(out)) ||
-    (points_item && points_item->write_off_point_set(out));
+
+  if(fileinfo.suffix().toLower() == "off"){
+    return (poly_item && poly_item->save(out)) || 
+      (soup_item && soup_item->save(out)) ||
+      (points_item && points_item->write_off_point_set(out));
+  }
+  if(fileinfo.suffix().toLower() == "obj"){
+    return (poly_item && poly_item->save_obj(out));
+  }
+  return false;
 }
 
 #include "OFF_io_plugin.moc"
diff --git a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
index f715f405970..7a2d38eae55 100644
--- a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.cpp
@@ -3,6 +3,8 @@
 #include <CGAL/AABB_intersections.h>
 #include "Kernel_type.h"
 #include <CGAL/IO/Polyhedron_iostream.h>
+#include <CGAL/IO/File_writer_wavefront.h>
+#include <CGAL/IO/generic_copy_OFF.h>
 
 #include <CGAL/AABB_tree.h>
 #include <CGAL/AABB_traits.h>
@@ -730,6 +732,15 @@ Scene_polyhedron_item::save(std::ostream& out) const
     return (bool) out;
 }
 
+bool
+Scene_polyhedron_item::save_obj(std::ostream& out) const
+{
+  CGAL::File_writer_wavefront  writer;
+  CGAL::generic_print_polyhedron(out, *poly, writer);
+  return out.good();
+}
+
+
 QString
 Scene_polyhedron_item::toolTip() const
 {
diff --git a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.h b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.h
index 4763502584e..aa16ea0ed20 100644
--- a/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_polyhedron_item.h
@@ -58,6 +58,7 @@ public:
     bool load(std::istream& in);
     bool load_obj(std::istream& in);
     bool save(std::ostream& out) const;
+    bool save_obj(std::ostream& out) const;
 
     // Function for displaying meta-data of the item
     virtual QString toolTip() const;