1 files changed, 116 insertions, 0 deletions
diff --git a/source/blender/io/common/intern/object_identifier.cc b/source/blender/io/common/intern/object_identifier.cc
new file mode 100644
index 00000000000..696bc5d2c34
--- /dev/null
+++ b/source/blender/io/common/intern/object_identifier.cc
@@ -0,0 +1,116 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2019 Blender Foundation.
+ * All rights reserved.
+ */
+#include "IO_abstract_hierarchy_iterator.h"
+
+#include "BKE_duplilist.h"
+
+extern "C" {
+#include <limits.h> /* For INT_MAX. */
+}
+#include <cstring>
+#include <sstream>
+
+namespace blender {
+namespace io {
+
+ObjectIdentifier::ObjectIdentifier(Object *object,
+                                   Object *duplicated_by,
+                                   const PersistentID &persistent_id)
+    : object(object), duplicated_by(duplicated_by), persistent_id(persistent_id)
+{
+}
+
+ObjectIdentifier::ObjectIdentifier(const ObjectIdentifier &other)
+    : object(other.object), duplicated_by(other.duplicated_by), persistent_id(other.persistent_id)
+{
+}
+
+ObjectIdentifier::~ObjectIdentifier()
+{
+}
+
+ObjectIdentifier ObjectIdentifier::for_real_object(Object *object)
+{
+  return ObjectIdentifier(object, nullptr, PersistentID());
+}
+
+ObjectIdentifier ObjectIdentifier::for_hierarchy_context(const HierarchyContext *context)
+{
+  if (context == nullptr) {
+    return for_graph_root();
+  }
+  if (context->duplicator != nullptr) {
+    return ObjectIdentifier(context->object, context->duplicator, context->persistent_id);
+  }
+  return for_real_object(context->object);
+}
+
+ObjectIdentifier ObjectIdentifier::for_duplicated_object(const DupliObject *dupli_object,
+                                                         Object *duplicated_by)
+{
+  return ObjectIdentifier(dupli_object->ob, duplicated_by, PersistentID(dupli_object));
+}
+
+ObjectIdentifier ObjectIdentifier::for_graph_root()
+{
+  return ObjectIdentifier(nullptr, nullptr, PersistentID());
+}
+
+bool ObjectIdentifier::is_root() const
+{
+  return object == nullptr;
+}
+
+bool operator<(const ObjectIdentifier &obj_ident_a, const ObjectIdentifier &obj_ident_b)
+{
+  if (obj_ident_a.object != obj_ident_b.object) {
+    return obj_ident_a.object < obj_ident_b.object;
+  }
+
+  if (obj_ident_a.duplicated_by != obj_ident_b.duplicated_by) {
+    return obj_ident_a.duplicated_by < obj_ident_b.duplicated_by;
+  }
+
+  if (obj_ident_a.duplicated_by == nullptr) {
+    /* Both are real objects, no need to check the persistent ID. */
+    return false;
+  }
+
+  /* Same object, both are duplicated, use the persistent IDs to determine order. */
+  return obj_ident_a.persistent_id < obj_ident_b.persistent_id;
+}
+
+bool operator==(const ObjectIdentifier &obj_ident_a, const ObjectIdentifier &obj_ident_b)
+{
+  if (obj_ident_a.object != obj_ident_b.object) {
+    return false;
+  }
+  if (obj_ident_a.duplicated_by != obj_ident_b.duplicated_by) {
+    return false;
+  }
+  if (obj_ident_a.duplicated_by == nullptr) {
+    return true;
+  }
+
+  /* Same object, both are duplicated, use the persistent IDs to determine equality. */
+  return obj_ident_a.persistent_id == obj_ident_b.persistent_id;
+}
+
+}  // namespace io
+}  // namespace blender