From 8e6bd07322ec1d283c21b2e8969bbc0e10a26c33 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Tue, 20 Feb 2024 13:12:23 +0100
Subject: [PATCH] Fix `Transform` diff serialization to properly handle prefab
 changes to a single component of transform

#2085
---
 Source/Engine/Serialization/JsonWriter.cpp    | 26 ++++++++++++++-----
 Source/Engine/Serialization/Serialization.cpp | 18 ++++++++++---
 Source/Engine/Serialization/Serialization.h   |  2 +-
 3 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/Source/Engine/Serialization/JsonWriter.cpp b/Source/Engine/Serialization/JsonWriter.cpp
index 27ecb672b..af7bb63a0 100644
--- a/Source/Engine/Serialization/JsonWriter.cpp
+++ b/Source/Engine/Serialization/JsonWriter.cpp
@@ -343,18 +343,30 @@ void JsonWriter::Transform(const ::Transform& value)
 void JsonWriter::Transform(const ::Transform& value, const ::Transform* other)
 {
     StartObject();
-    if (!other || !Vector3::NearEqual(value.Translation, other->Translation))
+    if (other)
+    {
+        if (!Vector3::NearEqual(value.Translation, other->Translation))
+        {
+            JKEY("Translation");
+            Vector3(value.Translation);
+        }
+        if (!Quaternion::NearEqual(value.Orientation, other->Orientation))
+        {
+            JKEY("Orientation");
+            Quaternion(value.Orientation);
+        }
+        if (!Float3::NearEqual(value.Scale, other->Scale))
+        {
+            JKEY("Scale");
+            Float3(value.Scale);
+        }
+    }
+    else
     {
         JKEY("Translation");
         Vector3(value.Translation);
-    }
-    if (!other || !Quaternion::NearEqual(value.Orientation, other->Orientation))
-    {
         JKEY("Orientation");
         Quaternion(value.Orientation);
-    }
-    if (!other || !Float3::NearEqual(value.Scale, other->Scale))
-    {
         JKEY("Scale");
         Float3(value.Scale);
     }
diff --git a/Source/Engine/Serialization/Serialization.cpp b/Source/Engine/Serialization/Serialization.cpp
index ac8eb41a9..1f8020288 100644
--- a/Source/Engine/Serialization/Serialization.cpp
+++ b/Source/Engine/Serialization/Serialization.cpp
@@ -747,9 +747,21 @@ bool Serialization::ShouldSerialize(const Transform& v, const void* otherObj)
 
 void Serialization::Deserialize(ISerializable::DeserializeStream& stream, Transform& v, ISerializeModifier* modifier)
 {
-    DESERIALIZE_HELPER(stream, "Translation", v.Translation, Vector3::Zero);
-    DESERIALIZE_HELPER(stream, "Scale", v.Scale, Vector3::One);
-    DESERIALIZE_HELPER(stream, "Orientation", v.Orientation, Quaternion::Identity);
+    {
+        const auto m = SERIALIZE_FIND_MEMBER(stream, "Translation");
+        if (m != stream.MemberEnd())
+            Deserialize(m->value, v.Translation, modifier);
+    }
+    {
+        const auto m = SERIALIZE_FIND_MEMBER(stream, "Scale");
+        if (m != stream.MemberEnd())
+            Deserialize(m->value, v.Scale, modifier);
+    }
+    {
+        const auto m = SERIALIZE_FIND_MEMBER(stream, "Orientation");
+        if (m != stream.MemberEnd())
+            Deserialize(m->value, v.Orientation, modifier);
+    }
 }
 
 bool Serialization::ShouldSerialize(const Matrix& v, const void* otherObj)
diff --git a/Source/Engine/Serialization/Serialization.h b/Source/Engine/Serialization/Serialization.h
index ed1008922..f7e8a0fcb 100644
--- a/Source/Engine/Serialization/Serialization.h
+++ b/Source/Engine/Serialization/Serialization.h
@@ -393,7 +393,7 @@ namespace Serialization
     FLAXENGINE_API bool ShouldSerialize(const Transform& v, const void* otherObj);
     inline void Serialize(ISerializable::SerializeStream& stream, const Transform& v, const void* otherObj)
     {
-        stream.Transform(v);
+        stream.Transform(v, (const Transform*)otherObj);
     }
     FLAXENGINE_API void Deserialize(ISerializable::DeserializeStream& stream, Transform& v, ISerializeModifier* modifier);