From a34378934d56f5c6183bb1f48f5c4fd4565c5e02 Mon Sep 17 00:00:00 2001
From: aramis_acg <aramis_acg@67173fc5-114c-0410-ac8e-9d2fd5bffc1f>
Date: Sun, 19 Oct 2008 21:26:52 +0000
Subject: [PATCH] Fixed a minor problem with the vertex format hash in the
 PretransformVertices step. Remember, the step seems still to swizzle
 materials in some cases.

git-svn-id: https://assimp.svn.sourceforge.net/svnroot/assimp/trunk@188 67173fc5-114c-0410-ac8e-9d2fd5bffc1f
---
 code/PretransformVertices.cpp | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/code/PretransformVertices.cpp b/code/PretransformVertices.cpp
index 46d570300..34c2e677d 100644
--- a/code/PretransformVertices.cpp
+++ b/code/PretransformVertices.cpp
@@ -95,13 +95,16 @@ unsigned int GetMeshVFormat(aiMesh* pcMesh)
 	if (pcMesh->mBones)
 		return (unsigned int)pcMesh->mBones;
 
-	unsigned int iRet = 0;
 	ai_assert(NULL != pcMesh->mVertices);
 
+	// FIX: the hash may never be 0. Otherwise a comparison against
+	// nullptr could be successful
+	unsigned int iRet = 1;
+
 	// normals
-	if (pcMesh->HasNormals())iRet |= 0x1;
+	if (pcMesh->HasNormals())iRet |= 0x2;
 	// tangents and bitangents
-	if (pcMesh->HasTangentsAndBitangents())iRet |= 0x2;
+	if (pcMesh->HasTangentsAndBitangents())iRet |= 0x4;
 
 	// texture coordinates
 	unsigned int p = 0;