diff --git a/Source/Engine/Physics/Colliders/CharacterController.cpp b/Source/Engine/Physics/Colliders/CharacterController.cpp
index 9b36a92ff..38ab0394d 100644
--- a/Source/Engine/Physics/Colliders/CharacterController.cpp
+++ b/Source/Engine/Physics/Colliders/CharacterController.cpp
@@ -206,7 +206,7 @@ void CharacterController::CreateController()
     _cachedScale = GetScale();
     const float scaling = _cachedScale.GetAbsolute().MaxValue();
     const Vector3 position = _transform.LocalToWorld(_center);
-    _controller = PhysicsBackend::CreateController(GetPhysicsScene()->GetPhysicsScene(), this, this, _contactOffset, position, _slopeLimit, (int32)_nonWalkableMode, Material.Get(), Math::Abs(_radius) * scaling, Math::Abs(_height) * scaling, _stepOffset, _shape);
+    _controller = PhysicsBackend::CreateController(GetPhysicsScene()->GetPhysicsScene(), this, this, _contactOffset, position, _slopeLimit, (int32)_nonWalkableMode, Material, Math::Abs(_radius) * scaling, Math::Abs(_height) * scaling, _stepOffset, _shape);
 
     // Setup
     PhysicsBackend::SetControllerUpDirection(_controller, _upDirection);
diff --git a/Source/Engine/Physics/Colliders/Collider.cpp b/Source/Engine/Physics/Colliders/Collider.cpp
index 4326a033d..e354057d2 100644
--- a/Source/Engine/Physics/Colliders/Collider.cpp
+++ b/Source/Engine/Physics/Colliders/Collider.cpp
@@ -201,7 +201,7 @@ void Collider::CreateShape()
 
     // Create shape
     const bool isTrigger = _isTrigger && CanBeTrigger();
-    _shape = PhysicsBackend::CreateShape(this, shape, Material.Get(), IsActiveInHierarchy(), isTrigger);
+    _shape = PhysicsBackend::CreateShape(this, shape, Material, IsActiveInHierarchy(), isTrigger);
     PhysicsBackend::SetShapeContactOffset(_shape, _contactOffset);
     UpdateLayerBits();
 }
@@ -288,7 +288,7 @@ void Collider::OnMaterialChanged()
 {
     // Update the shape material
     if (_shape)
-        PhysicsBackend::SetShapeMaterial(_shape, Material.Get());
+        PhysicsBackend::SetShapeMaterial(_shape, Material);
 }
 
 void Collider::BeginPlay(SceneBeginData* data)
diff --git a/Source/Engine/Physics/Colliders/Collider.h b/Source/Engine/Physics/Colliders/Collider.h
index bd17aa27a..cbbb7e522 100644
--- a/Source/Engine/Physics/Colliders/Collider.h
+++ b/Source/Engine/Physics/Colliders/Collider.h
@@ -4,7 +4,7 @@
 
 #include "Engine/Physics/Types.h"
 #include "Engine/Content/JsonAsset.h"
-#include "Engine/Content/AssetReference.h"
+#include "Engine/Content/JsonAssetReference.h"
 #include "Engine/Physics/Actors/PhysicsColliderActor.h"
 
 struct RayCastHit;
@@ -80,8 +80,8 @@ public:
     /// <summary>
     /// The physical material used to define the collider physical properties.
     /// </summary>
-    API_FIELD(Attributes="EditorOrder(2), DefaultValue(null), AssetReference(typeof(PhysicalMaterial), true), EditorDisplay(\"Collider\")")
-    AssetReference<JsonAsset> Material;
+    API_FIELD(Attributes="EditorOrder(2), DefaultValue(null), EditorDisplay(\"Collider\")")
+    JsonAssetReference<PhysicalMaterial> Material;
 
 public:
     /// <summary>
diff --git a/Source/Engine/Physics/PhysicalMaterial.h b/Source/Engine/Physics/PhysicalMaterial.h
index ff27437e8..f1aa0c1fd 100644
--- a/Source/Engine/Physics/PhysicalMaterial.h
+++ b/Source/Engine/Physics/PhysicalMaterial.h
@@ -15,17 +15,9 @@ class FLAXENGINE_API PhysicalMaterial final : public ISerializable
     API_AUTO_SERIALIZATION();
     DECLARE_SCRIPTING_TYPE_MINIMAL(PhysicalMaterial);
 private:
-    void* _material;
+    void* _material = nullptr;
 
 public:
-    /// <summary>
-    /// Initializes a new instance of the <see cref="PhysicalMaterial"/> class.
-    /// </summary>
-    PhysicalMaterial();
-
-    /// <summary>
-    /// Finalizes an instance of the <see cref="PhysicalMaterial"/> class.
-    /// </summary>
     ~PhysicalMaterial();
 
 public:
diff --git a/Source/Engine/Physics/Physics.cpp b/Source/Engine/Physics/Physics.cpp
index 5d9b218ec..942f1b79b 100644
--- a/Source/Engine/Physics/Physics.cpp
+++ b/Source/Engine/Physics/Physics.cpp
@@ -78,11 +78,6 @@ void PhysicsSettings::Deserialize(DeserializeStream& stream, ISerializeModifier*
     }
 }
 
-PhysicalMaterial::PhysicalMaterial()
-    : _material(nullptr)
-{
-}
-
 PhysicalMaterial::~PhysicalMaterial()
 {
     if (_material)
diff --git a/Source/Engine/Terrain/Terrain.cpp b/Source/Engine/Terrain/Terrain.cpp
index f347e3732..772abf4d3 100644
--- a/Source/Engine/Terrain/Terrain.cpp
+++ b/Source/Engine/Terrain/Terrain.cpp
@@ -239,7 +239,7 @@ void Terrain::OnPhysicalMaterialChanged()
         const auto patch = _patches[pathIndex];
         if (patch->HasCollision())
         {
-            PhysicsBackend::SetShapeMaterial(patch->_physicsShape, PhysicalMaterial.Get());
+            PhysicsBackend::SetShapeMaterial(patch->_physicsShape, PhysicalMaterial);
         }
     }
 }
diff --git a/Source/Engine/Terrain/Terrain.h b/Source/Engine/Terrain/Terrain.h
index 636f30206..1f495c5ab 100644
--- a/Source/Engine/Terrain/Terrain.h
+++ b/Source/Engine/Terrain/Terrain.h
@@ -2,7 +2,7 @@
 
 #pragma once
 
-#include "Engine/Content/JsonAsset.h"
+#include "Engine/Content/JsonAssetReference.h"
 #include "Engine/Content/Assets/MaterialBase.h"
 #include "Engine/Physics/Actors/PhysicsColliderActor.h"
 
@@ -79,8 +79,8 @@ public:
     /// <summary>
     /// The physical material used to define the terrain collider physical properties.
     /// </summary>
-    API_FIELD(Attributes="EditorOrder(520), DefaultValue(null), Limit(-1, 100, 0.1f), EditorDisplay(\"Collision\"), AssetReference(typeof(PhysicalMaterial), true)")
-    AssetReference<JsonAsset> PhysicalMaterial;
+    API_FIELD(Attributes="EditorOrder(520), DefaultValue(null), Limit(-1, 100, 0.1f), EditorDisplay(\"Collision\")")
+    JsonAssetReference<::PhysicalMaterial> PhysicalMaterial;
 
     /// <summary>
     /// The draw passes to use for rendering this object.
diff --git a/Source/Engine/Terrain/TerrainPatch.cpp b/Source/Engine/Terrain/TerrainPatch.cpp
index 8e05062c8..7fa449601 100644
--- a/Source/Engine/Terrain/TerrainPatch.cpp
+++ b/Source/Engine/Terrain/TerrainPatch.cpp
@@ -2125,7 +2125,7 @@ void TerrainPatch::CreateCollision()
     shape.SetHeightField(_physicsHeightField, heightScale, rowScale, columnScale);
 
     // Create shape
-    _physicsShape = PhysicsBackend::CreateShape(_terrain, shape, _terrain->PhysicalMaterial.Get(), _terrain->IsActiveInHierarchy(), false);
+    _physicsShape = PhysicsBackend::CreateShape(_terrain, shape, _terrain->PhysicalMaterial, _terrain->IsActiveInHierarchy(), false);
     PhysicsBackend::SetShapeLocalPose(_physicsShape, Vector3(0, _yOffset * terrainTransform.Scale.Y, 0), Quaternion::Identity);
 
     // Create static actor