Fix for ReadMesh error reporting

Gems/WhiteBox/Code/Include/WhiteBox/WhiteBoxToolApi.h

@@ -729,15 +729,29 @@ namespace WhiteBox
         ///////////////////////////////////////////////////////////////////////////////////////////////////////////////
         // Serialization
 
+        //! The result of attempting to deserialize a white box mesh from a white box mesh stream.
+        enum class ReadResult
+        {
+            Full, //!< The white box mesh stream was full and was read into white box mesh (it is now initialized).
+            Empty, //!< The white box mesh stream was empty so no white box mesh was loaded.
+            Error //!< An error occurred while trying to deserialize white box mesh stream.
+        };
+
         //! Take an input stream of bytes and create a white box mesh from the deserialized data.
-        //! @return Will return false if any error was encountered during deserialization, true otherwise.
+        //! @return Will return ReadResult::Full if the white box mesh stream was filled with data and
+        //! the white box mesh was initialized, ReadResult::Empty if white box mesh stream did not contain
+        //! any data (white box mesh will be left empty) or ReadResult::Error if any error was encountered
+        //! during deserialization.
         //! @note A white box mesh must have been created first.
-        bool ReadMesh(WhiteBoxMesh& whiteBox, const WhiteBoxMeshStream& input);
+        ReadResult ReadMesh(WhiteBoxMesh& whiteBox, const WhiteBoxMeshStream& input);
 
         //! Take an input stream and create a white box mesh from the deserialized data.
-        //! @return Will return false if any error was encountered during deserialization, true otherwise.
+        //! @return Will return ReadResult::Full if the white box mesh stream was filled with data and
+        //! the white box mesh was initialized, ReadResult::Empty if white box mesh stream did not contain
+        //! any data (white box mesh will be left empty) or ReadResult::Error if any error was encountered
+        //! during deserialization.
         //! @note The input stream must not skip white space characters (std::noskipws must be set on the stream).
-        bool ReadMesh(WhiteBoxMesh& whiteBox, std::istream& input);
+        ReadResult ReadMesh(WhiteBoxMesh& whiteBox, std::istream& input);
 
         //! Take a white box mesh and write it out to a stream of bytes.
         //! @return Will return false if any error was encountered during serialization, true otherwise.

Gems/WhiteBox/Code/Source/Asset/WhiteBoxMeshAssetHandler.cpp

@@ -118,12 +118,15 @@ namespace WhiteBox
             stream->Read(size, whiteBoxData.data());
 
             auto whiteBoxMesh = WhiteBox::Api::CreateWhiteBoxMesh();
-            const bool success = WhiteBox::Api::ReadMesh(*whiteBoxMesh, whiteBoxData);
+            const auto result = WhiteBox::Api::ReadMesh(*whiteBoxMesh, whiteBoxData);
 
+            // if result is not 'Full', then whiteBoxMeshAsset could be empty which is most likely an error
+            // as no data was loaded from the asset, or it was not correctly read in stream->Read(..)
+            const auto success = result == Api::ReadResult::Full;
             if (success)
             {
                 whiteBoxMeshAsset->SetMesh(AZStd::move(whiteBoxMesh));
-                whiteBoxMeshAsset->SetWhiteBoxData(whiteBoxData);
+                whiteBoxMeshAsset->SetWhiteBoxData(AZStd::move(whiteBoxData));
             }
 
             return success ? AZ::Data::AssetHandler::LoadResult::LoadComplete

Gems/WhiteBox/Code/Source/Core/WhiteBoxToolApi.cpp

@@ -3403,13 +3403,13 @@ namespace WhiteBox
             return false;
         }
 
-        bool ReadMesh(WhiteBoxMesh& whiteBox, const WhiteBoxMeshStream& input)
+        ReadResult ReadMesh(WhiteBoxMesh& whiteBox, const WhiteBoxMeshStream& input)
         {
             AZ_PROFILE_FUNCTION(AZ::Debug::ProfileCategory::AzToolsFramework);
 
             if (input.empty())
             {
-                return false;
+                return ReadResult::Empty;
             }
 
             std::string inputStr;
@@ -3423,19 +3423,19 @@ namespace WhiteBox
             return ReadMesh(whiteBox, whiteBoxStream);
         }
 
-        bool ReadMesh(WhiteBoxMesh& whiteBox, std::istream& input)
+        ReadResult ReadMesh(WhiteBoxMesh& whiteBox, std::istream& input)
         {
             const auto skipws = input.flags() & std::ios_base::skipws;
             AZ_Assert(skipws == 0, "Input stream must not skip white space characters");
 
             if (skipws != 0)
             {
-                return false;
+                return ReadResult::Error;
             }
 
             AZStd::lock_guard lg(g_omSerializationLock);
             OpenMesh::IO::Options options{OpenMesh::IO::Options::FaceTexCoord | OpenMesh::IO::Options::FaceNormal};
-            return OpenMesh::IO::read_mesh(whiteBox.mesh, input, ".om", options);
+            return OpenMesh::IO::read_mesh(whiteBox.mesh, input, ".om", options) ? ReadResult::Full : ReadResult::Error;
         }
 
         WhiteBoxMeshPtr CloneMesh(const WhiteBoxMesh& whiteBox)
@@ -3449,7 +3449,7 @@ namespace WhiteBox
             }
 
             WhiteBoxMeshPtr newMesh = CreateWhiteBoxMesh();
-            if (!ReadMesh(*newMesh, clonedData))
+            if (ReadMesh(*newMesh, clonedData) != ReadResult::Full)
             {
                 return nullptr;
             }

Gems/WhiteBox/Code/Source/EditorWhiteBoxComponent.cpp

@@ -348,14 +348,14 @@ namespace WhiteBox
         else
         {
             // attempt to load the mesh
-            if (Api::ReadMesh(*m_whiteBox, m_whiteBoxData))
+            const auto result = Api::ReadMesh(*m_whiteBox, m_whiteBoxData);
+            AZ_Error("EditorWhiteBoxComponent", result != WhiteBox::Api::ReadResult::Error, "Error deserializing white box mesh stream");
+
+            // if the read was successful but the byte stream is empty
+            // (there was nothing to load), create a default mesh
+            if (result == Api::ReadResult::Empty)
             {
-                // if the read was successful but the byte stream is empty
-                // (there was nothing to load), create a default mesh
-                if (m_whiteBoxData.empty())
-                {
-                    Api::InitializeAsUnitCube(*m_whiteBox);
-                }
+                Api::InitializeAsUnitCube(*m_whiteBox);
             }
         }
     }

Gems/WhiteBox/Code/Tests/WhiteBoxTest.cpp

@@ -470,6 +470,7 @@ namespace UnitTest
     TEST_F(WhiteBoxTestFixture, MeshNotDeserializedWithSkipWhiteSpaceStream)
     {
         namespace Api = WhiteBox::Api;
+        using testing::Eq;
 
         Api::InitializeAsUnitCube(*m_whiteBox);
         AZStd::vector<AZ::u8> serializedWhiteBox;
@@ -485,7 +486,7 @@ namespace UnitTest
         // note: std::stringstream will default to skip white space characters
 
         AZ_TEST_START_TRACE_SUPPRESSION;
-        EXPECT_FALSE(Api::ReadMesh(*m_whiteBox, whiteBoxStream));
+        EXPECT_THAT(Api::ReadMesh(*m_whiteBox, whiteBoxStream), Eq(Api::ReadResult::Error));
         AZ_TEST_STOP_TRACE_SUPPRESSION(1);
     }