From fabfcf3cb0fa5308626907a58313a69ca27f360a Mon Sep 17 00:00:00 2001
From: Malcolm Tyrrell <matyrr@microsoft.com>
Date: Thu, 5 Dec 2019 11:37:22 +0000
Subject: [PATCH] More checking

---
 code/Common/Importer.cpp     |  6 +++++-
 code/FBX/FBXConverter.cpp    | 12 +++++++++---
 code/glTF/glTFImporter.cpp   | 17 ++++++++++++++---
 code/glTF2/glTF2Importer.cpp | 17 ++++++++++++++---
 4 files changed, 42 insertions(+), 10 deletions(-)

diff --git a/code/Common/Importer.cpp b/code/Common/Importer.cpp
index d7ca88545..bf5cb2bf6 100644
--- a/code/Common/Importer.cpp
+++ b/code/Common/Importer.cpp
@@ -655,8 +655,12 @@ const aiScene* Importer::ReadFile( const char* _pFile, unsigned int pFlags)
 
         // If successful, apply all active post processing steps to the imported data
         if( pimpl->mScene)  {
-            if (!pimpl->mScene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT))
+            if (!pimpl->mScene->mMetaData || !pimpl->mScene->mMetaData->HasKey(AI_METADATA_SOURCE_FORMAT))
             {
+                if (!pimpl->mScene->mMetaData)
+                {
+                    pimpl->mScene->mMetaData = new aiMetadata;
+                }
                 pimpl->mScene->mMetaData->Add(AI_METADATA_SOURCE_FORMAT, aiString(ext));
             }
 
diff --git a/code/FBX/FBXConverter.cpp b/code/FBX/FBXConverter.cpp
index f50688bea..46b899810 100644
--- a/code/FBX/FBXConverter.cpp
+++ b/code/FBX/FBXConverter.cpp
@@ -61,6 +61,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <assimp/CreateAnimMesh.h>
 #include <assimp/commonMetaData.h>
+#include <assimp/StringUtils.h>
 
 #include <tuple>
 #include <memory>
@@ -3605,7 +3606,9 @@ void FBXConverter::SetShadingPropertiesRaw(aiMaterial* out_mat, const PropertyTa
                 return;
             }
 
-            out->mMetaData = aiMetadata::Alloc(17);
+            const bool hasGenerator = !doc.Creator().empty();
+
+            out->mMetaData = aiMetadata::Alloc(16 + (hasGenerator ? 1 : 0));
             out->mMetaData->Set(0, "UpAxis", doc.GlobalSettings().UpAxis());
             out->mMetaData->Set(1, "UpAxisSign", doc.GlobalSettings().UpAxisSign());
             out->mMetaData->Set(2, "FrontAxis", doc.GlobalSettings().FrontAxis());
@@ -3621,8 +3624,11 @@ void FBXConverter::SetShadingPropertiesRaw(aiMaterial* out_mat, const PropertyTa
             out->mMetaData->Set(12, "TimeSpanStart", doc.GlobalSettings().TimeSpanStart());
             out->mMetaData->Set(13, "TimeSpanStop", doc.GlobalSettings().TimeSpanStop());
             out->mMetaData->Set(14, "CustomFrameRate", doc.GlobalSettings().CustomFrameRate());
-            out->mMetaData->Set(15, AI_METADATA_SOURCE_FORMAT_VERSION, aiString(std::to_string(doc.FBXVersion())));
-            out->mMetaData->Set(16, AI_METADATA_SOURCE_GENERATOR, aiString(doc.Creator()));
+            out->mMetaData->Set(15, AI_METADATA_SOURCE_FORMAT_VERSION, aiString(to_string(doc.FBXVersion())));
+            if (hasGenerator)
+            {
+                out->mMetaData->Set(16, AI_METADATA_SOURCE_GENERATOR, aiString(doc.Creator()));
+            }
         }
 
         void FBXConverter::TransferDataToScene()
diff --git a/code/glTF/glTFImporter.cpp b/code/glTF/glTFImporter.cpp
index 50ae7541d..25691b2c9 100644
--- a/code/glTF/glTFImporter.cpp
+++ b/code/glTF/glTFImporter.cpp
@@ -701,9 +701,20 @@ void glTFImporter::ImportEmbeddedTextures(glTF::Asset& r)
 void glTFImporter::ImportCommonMetadata(glTF::Asset& a)
 {
     ai_assert(mScene->mMetaData == nullptr);
-    mScene->mMetaData = aiMetadata::Alloc(2);
-    mScene->mMetaData->Set(0, AI_METADATA_SOURCE_FORMAT_VERSION, aiString(a.asset.version));
-    mScene->mMetaData->Set(1, AI_METADATA_SOURCE_GENERATOR, aiString(a.asset.generator));
+    const bool hasVersion = !a.asset.version.empty();
+    const bool hasGenerator = !a.asset.generator.empty();
+    if (hasVersion || hasGenerator)
+    {
+        mScene->mMetaData = new aiMetadata;
+        if (hasVersion)
+        {
+            mScene->mMetaData->Add(AI_METADATA_SOURCE_FORMAT_VERSION, aiString(a.asset.version));
+        }
+        if (hasGenerator)
+        {
+            mScene->mMetaData->Add(AI_METADATA_SOURCE_GENERATOR, aiString(a.asset.generator));
+        }
+    }
 }
 
 void glTFImporter::InternReadFile(const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler)
diff --git a/code/glTF2/glTF2Importer.cpp b/code/glTF2/glTF2Importer.cpp
index 70b6ddd70..b14d68c27 100644
--- a/code/glTF2/glTF2Importer.cpp
+++ b/code/glTF2/glTF2Importer.cpp
@@ -1304,9 +1304,20 @@ void glTF2Importer::ImportEmbeddedTextures(glTF2::Asset &r) {
 
 void glTF2Importer::ImportCommonMetadata(glTF2::Asset& a) {
     ai_assert(mScene->mMetaData == nullptr);
-    mScene->mMetaData = aiMetadata::Alloc(2);
-    mScene->mMetaData->Set(0, AI_METADATA_SOURCE_FORMAT_VERSION, aiString(a.asset.version));
-    mScene->mMetaData->Set(1, AI_METADATA_SOURCE_GENERATOR, aiString(a.asset.generator));
+    const bool hasVersion = !a.asset.version.empty();
+    const bool hasGenerator = !a.asset.generator.empty();
+    if (hasVersion || hasGenerator)
+    {
+        mScene->mMetaData = new aiMetadata;
+        if (hasVersion)
+        {
+            mScene->mMetaData->Add(AI_METADATA_SOURCE_FORMAT_VERSION, aiString(a.asset.version));
+        }
+        if (hasGenerator)
+        {
+            mScene->mMetaData->Add(AI_METADATA_SOURCE_GENERATOR, aiString(a.asset.generator));
+        }
+    }
 }
 
 void glTF2Importer::InternReadFile(const std::string &pFile, aiScene *pScene, IOSystem *pIOHandler) {