From 6a9ccf2016016cf71b3c3fd0a458f20e436e9273 Mon Sep 17 00:00:00 2001
From: Alexandr Arutjunov <smal.root@gmail.com>
Date: Mon, 26 Sep 2016 13:01:38 +0300
Subject: [PATCH] [+] Flag for scene for supporting formats where more than one
 face can reference to one vertex.

---
 code/ValidateDataStructure.cpp | 5 +++--
 include/assimp/scene.h         | 9 ++++++++-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/code/ValidateDataStructure.cpp b/code/ValidateDataStructure.cpp
index fd6867012..44e361f71 100644
--- a/code/ValidateDataStructure.cpp
+++ b/code/ValidateDataStructure.cpp
@@ -1,4 +1,4 @@
-/*
+/*
 ---------------------------------------------------------------------------
 Open Asset Import Library (assimp)
 ---------------------------------------------------------------------------
@@ -408,7 +408,8 @@ void ValidateDSProcess::Validate( const aiMesh* pMesh)
             // the MSB flag is temporarily used by the extra verbose
             // mode to tell us that the JoinVerticesProcess might have
             // been executed already.
-            if ( !(this->mScene->mFlags & AI_SCENE_FLAGS_NON_VERBOSE_FORMAT ) && abRefList[face.mIndices[a]])
+			if ( !(this->mScene->mFlags & AI_SCENE_FLAGS_NON_VERBOSE_FORMAT ) && !(this->mScene->mFlags & AI_SCENE_FLAGS_ALLOW_SHARED) &&
+				abRefList[face.mIndices[a]])
             {
                 ReportError("aiMesh::mVertices[%i] is referenced twice - second "
                     "time by aiMesh::mFaces[%i]::mIndices[%i]",face.mIndices[a],i,a);
diff --git a/include/assimp/scene.h b/include/assimp/scene.h
index 398f712b4..80542a67b 100644
--- a/include/assimp/scene.h
+++ b/include/assimp/scene.h
@@ -1,4 +1,4 @@
-/*
+/*
 ---------------------------------------------------------------------------
 Open Asset Import Library (assimp)
 ---------------------------------------------------------------------------
@@ -266,6 +266,13 @@ struct aiNode
  */
 #define AI_SCENE_FLAGS_TERRAIN 0x10
 
+ /**
+ * Specifies that the scene data can be shared between structures. For example:
+ * one vertex in few faces. \ref AI_SCENE_FLAGS_NON_VERBOSE_FORMAT can not be
+ * used for this because \ref AI_SCENE_FLAGS_NON_VERBOSE_FORMAT has internal
+ * meaning about postprocessing steps.
+ */
+#define AI_SCENE_FLAGS_ALLOW_SHARED			0x20
 
 // -------------------------------------------------------------------------------
 /** The root structure of the imported data.