From 284c971ec0e1242664aa25280cc89cd3e260b4bb Mon Sep 17 00:00:00 2001
From: nothingTVatYT <rjakob13@googlemail.com>
Date: Fri, 5 Jan 2024 05:07:08 +0100
Subject: [PATCH] don't rotate a rigidbody around locked axis

---
 Source/Engine/Level/Actors/AnimatedModel.cpp | 29 +++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/Source/Engine/Level/Actors/AnimatedModel.cpp b/Source/Engine/Level/Actors/AnimatedModel.cpp
index c1b5af398..2ff4def5f 100644
--- a/Source/Engine/Level/Actors/AnimatedModel.cpp
+++ b/Source/Engine/Level/Actors/AnimatedModel.cpp
@@ -15,6 +15,7 @@
 #include "Engine/Graphics/Models/MeshDeformation.h"
 #include "Engine/Level/Scene/Scene.h"
 #include "Engine/Level/SceneObjectsFactory.h"
+#include "Engine/Physics/Actors/RigidBody.h"
 #include "Engine/Serialization/Serialization.h"
 
 AnimatedModel::AnimatedModel(const SpawnParams& params)
@@ -548,7 +549,33 @@ void AnimatedModel::ApplyRootMotion(const Transform& rootMotionDelta)
 
     // Apply movement
     Actor* target = RootMotionTarget ? RootMotionTarget.Get() : this;
-    target->AddMovement(translation, rootMotionDelta.Orientation);
+    // filter rotation according to constraints if the target is a rigidbody
+    const auto rigidBody = dynamic_cast<RigidBody*>(target);
+    auto rotation = rootMotionDelta.Orientation;
+    if (rigidBody)
+    {
+        if (static_cast<unsigned int>(rigidBody->GetConstraints()) & static_cast<unsigned int>(RigidbodyConstraints::LockRotation))
+            rotation = Quaternion::Identity;
+        else
+        {
+            Float3 euler = rotation.GetEuler();
+            const auto constraints = static_cast<unsigned int>(rigidBody->GetConstraints());
+            if (constraints & static_cast<unsigned int>(RigidbodyConstraints::LockRotationX))
+            {
+                euler.X = 0;
+            }
+            if (constraints & static_cast<unsigned int>(RigidbodyConstraints::LockRotationY))
+            {
+                euler.Y = 0;
+            }
+            if (constraints & static_cast<unsigned int>(RigidbodyConstraints::LockRotationZ))
+            {
+                euler.Z = 0;
+            }
+            rotation = Quaternion::Euler(euler);
+        }
+    }
+    target->AddMovement(translation, rotation);
 }
 
 void AnimatedModel::SyncParameters()