Adds feature for creating multiple physics scenes

Source/Engine/Level/Actor.cpp

@@ -17,6 +17,7 @@
 #include "Engine/Debug/Exceptions/JsonParseException.h"
 #include "Engine/Graphics/RenderTask.h"
 #include "Engine/Graphics/RenderView.h"
+#include "Engine/Physics/Physics.h"
 #include "Engine/Profiler/ProfilerCPU.h"
 #include "Engine/Scripting/Scripting.h"
 #include "Engine/Serialization/ISerializeModifier.h"
@@ -77,6 +78,7 @@ Actor::Actor(const SpawnParams& params)
     , _transform(Transform::Identity)
     , _sphere(BoundingSphere::Empty)
     , _box(BoundingBox::Zero)
+    , _physicsScene(nullptr)
     , HideFlags(HideFlags::None)
 {
 }
@@ -1809,3 +1811,26 @@ void Actor::FromJson(const StringAnsiView& json)
     Scripting::ObjectsLookupIdMapping.Set(nullptr);
     OnTransformChanged();
 }
+
+void Actor::SetPhysicsScene(PhysicsScene* scene)
+{
+    ASSERT(scene);
+
+    auto previous = GetPhysicsScene();
+    _physicsScene = scene;
+
+    if (previous != _physicsScene)
+        OnPhysicsSceneChanged(previous);
+
+    // cascade
+    for (auto child : Children)
+        child->SetPhysicsScene(scene);
+}
+
+PhysicsScene* Actor::GetPhysicsScene()
+{
+    if (_physicsScene == nullptr)
+        _physicsScene = Physics::DefaultScene;
+
+     return _physicsScene;
+}

Source/Engine/Level/Actor.h

@@ -14,6 +14,7 @@ struct RenderView;
 struct RenderContext;
 class GPUContext;
 class MemoryWriteStream;
+class PhysicsScene;
 class SceneRendering;
 class SceneRenderTask;
 
@@ -47,6 +48,7 @@ protected:
     BoundingSphere _sphere;
     BoundingBox _box;
     String _name;
+    PhysicsScene* _physicsScene;
 
 private:
 
@@ -959,6 +961,20 @@ public:
     /// <returns>The scene rendering interface.</returns>
     SceneRendering* GetSceneRendering() const;
 
+public:
+    /// <summary>
+    /// Set the physics world the controller is part of.
+    /// </summary>
+    API_PROPERTY(Attributes="HideInEditor") void SetPhysicsScene(PhysicsScene* scene);
+
+    /// <summary>
+    /// Get the physics world the controller is part of.
+    /// </summary>
+    API_PROPERTY(Attributes="HideInEditor") PhysicsScene* GetPhysicsScene();
+
+protected:
+    virtual void OnPhysicsSceneChanged(PhysicsScene* previous) {};
+
 private:
 
     void SetSceneInHierarchy(Scene* scene);

Source/Engine/Level/Level.cpp

@@ -22,6 +22,7 @@
 #include "Engine/Profiler/ProfilerCPU.h"
 #include "Engine/Scripting/Script.h"
 #include "Engine/Engine/Time.h"
+#include "Engine/Physics/Physics.h"
 #include "Engine/Scripting/ManagedCLR/MAssembly.h"
 #include "Engine/Scripting/ManagedCLR/MClass.h"
 #include "Engine/Scripting/ManagedCLR/MDomain.h"
@@ -164,6 +165,8 @@ bool LevelImpl::spawnActor(Actor* actor, Actor* parent)
         }
         if (parent == nullptr)
             parent = Level::Scenes[0];
+
+        actor->SetPhysicsScene(parent->GetPhysicsScene());
         actor->SetParent(parent, true, true);
     }
 
@@ -776,6 +779,8 @@ bool LevelImpl::unloadScene(Scene* scene)
     // Force flush deleted objects so we actually delete unloaded scene objects (prevent from reloading their managed objects, etc.)
     ObjectsRemovalService::Flush();
 
+    Physics::EndPlay();
+
     return false;
 }
 
@@ -1026,6 +1031,8 @@ bool Level::loadScene(rapidjson_flax::Value& data, int32 engineBuild, Scene** ou
     {
         PROFILE_CPU_NAMED("BeginPlay");
 
+        Physics::BeginPlay();
+
         ScopeLock lock(ScenesLock);
         Scenes.Add(scene);
         SceneBeginData beginData;