From 873a358ce483c742f502f5b80a3af73ab134425a Mon Sep 17 00:00:00 2001
From: Mike Samsonov <misams@microsoft.com>
Date: Wed, 28 Aug 2019 18:42:49 +0100
Subject: [PATCH] A crash in the aiMesh descructor

---
 CMakeLists.txt                    |  2 +-
 code/Common/SceneCombiner.cpp     | 29 +++++++++++++++++++++++++++++
 include/assimp/SceneCombiner.h    |  2 ++
 test/unit/utglTF2ImportExport.cpp |  9 +++++++++
 4 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c1517e93c..61251f85a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -253,7 +253,7 @@ ELSEIF(MSVC)
   IF(MSVC12)
     ADD_COMPILE_OPTIONS(/wd4351)
   ENDIF()
-  SET(CMAKE_CXX_FLAGS_DEBUG "/D_DEBUG /MDd /Ob2")
+  SET(CMAKE_CXX_FLAGS_DEBUG "/D_DEBUG /MDd /Ob2 /DEBUG:FULL /Zi")
 ELSEIF ( "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" )
   IF(NOT HUNTER_ENABLED)
     SET(CMAKE_CXX_FLAGS "-fPIC -std=c++11 ${CMAKE_CXX_FLAGS}")
diff --git a/code/Common/SceneCombiner.cpp b/code/Common/SceneCombiner.cpp
index e445bd743..4e6bc5b47 100644
--- a/code/Common/SceneCombiner.cpp
+++ b/code/Common/SceneCombiner.cpp
@@ -1091,6 +1091,35 @@ void SceneCombiner::Copy( aiMesh** _dest, const aiMesh* src ) {
         aiFace& f = dest->mFaces[i];
         GetArrayCopy(f.mIndices,f.mNumIndices);
     }
+
+    // make a deep copy of all blend shapes
+    CopyPtrArray(dest->mAnimMeshes, dest->mAnimMeshes, dest->mNumAnimMeshes);
+}
+
+// ------------------------------------------------------------------------------------------------
+void SceneCombiner::Copy(aiAnimMesh** _dest, const aiAnimMesh* src) {
+    if (nullptr == _dest || nullptr == src) {
+        return;
+    }
+
+    aiAnimMesh* dest = *_dest = new aiAnimMesh();
+
+    // get a flat copy
+    ::memcpy(dest, src, sizeof(aiAnimMesh));
+
+    // and reallocate all arrays
+    GetArrayCopy(dest->mVertices, dest->mNumVertices);
+    GetArrayCopy(dest->mNormals, dest->mNumVertices);
+    GetArrayCopy(dest->mTangents, dest->mNumVertices);
+    GetArrayCopy(dest->mBitangents, dest->mNumVertices);
+
+    unsigned int n = 0;
+    while (dest->HasTextureCoords(n))
+        GetArrayCopy(dest->mTextureCoords[n++], dest->mNumVertices);
+
+    n = 0;
+    while (dest->HasVertexColors(n))
+        GetArrayCopy(dest->mColors[n++], dest->mNumVertices);
 }
 
 // ------------------------------------------------------------------------------------------------
diff --git a/include/assimp/SceneCombiner.h b/include/assimp/SceneCombiner.h
index 679a2acea..f69a25f43 100644
--- a/include/assimp/SceneCombiner.h
+++ b/include/assimp/SceneCombiner.h
@@ -65,6 +65,7 @@ struct aiLight;
 struct aiMetadata;
 struct aiBone;
 struct aiMesh;
+struct aiAnimMesh;
 struct aiAnimation;
 struct aiNodeAnim;
 
@@ -363,6 +364,7 @@ public:
     static void Copy     (aiMesh** dest, const aiMesh* src);
 
     // similar to Copy():
+    static void Copy  (aiAnimMesh** dest, const aiAnimMesh* src);
     static void Copy  (aiMaterial** dest, const aiMaterial* src);
     static void Copy  (aiTexture** dest, const aiTexture* src);
     static void Copy  (aiAnimation** dest, const aiAnimation* src);
diff --git a/test/unit/utglTF2ImportExport.cpp b/test/unit/utglTF2ImportExport.cpp
index 0ba5226cc..1e8e4af9d 100644
--- a/test/unit/utglTF2ImportExport.cpp
+++ b/test/unit/utglTF2ImportExport.cpp
@@ -380,4 +380,13 @@ TEST_F( utglTF2ImportExport, exportglTF2FromFileTest ) {
     EXPECT_TRUE( exporterTest() );
 }
 
+TEST_F( utglTF2ImportExport, crash_in_anim_mesh_destructor ) {
+    Assimp::Importer importer;
+    const aiScene *scene = importer.ReadFile( ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Sample-Models/AnimatedMorphCube-glTF/AnimatedMorphCube.gltf",
+        aiProcess_ValidateDataStructure);
+    ASSERT_NE( nullptr, scene );
+    Assimp::Exporter exporter;
+    ASSERT_EQ(aiReturn_SUCCESS, exporter.Export(scene, "glb2", ASSIMP_TEST_MODELS_DIR "/glTF2/glTF-Sample-Models/AnimatedMorphCube-glTF/AnimatedMorphCube_out.glTF"));
+}
+
 #endif // ASSIMP_BUILD_NO_EXPORT