From d93ea8e49bb36ae96c33e71497b1d3697487fe89 Mon Sep 17 00:00:00 2001
From: Kah Wei <msntkw@msn.com>
Date: Thu, 10 Nov 2022 23:34:53 +0800
Subject: [PATCH] Child caches are now updated when scene hierarchy changes

---
 SHADE_Engine/src/Scripting/SHScriptEngine.cpp | 38 ++++++++++++++++++-
 SHADE_Engine/src/Scripting/SHScriptEngine.h   |  3 ++
 SHADE_Managed/src/Engine/GameObject.cxx       |  3 +-
 3 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/SHADE_Engine/src/Scripting/SHScriptEngine.cpp b/SHADE_Engine/src/Scripting/SHScriptEngine.cpp
index 276eeb24..f279bec1 100644
--- a/SHADE_Engine/src/Scripting/SHScriptEngine.cpp
+++ b/SHADE_Engine/src/Scripting/SHScriptEngine.cpp
@@ -318,6 +318,20 @@ namespace SHADE
     return eventData->handle;
   }
 
+  SHEventHandle SHScriptEngine::onSceneNodeChildrenAdded(SHEventPtr eventPtr)
+  {
+    auto eventData = reinterpret_cast<const SHEventSpec<SHSceneGraphAddChildEvent>*>(eventPtr.get());
+    csSceneNodeChildrenChanged(eventData->data->parent->GetEntityID());
+    return eventData->handle;
+  }
+
+  SHEventHandle SHScriptEngine::onSceneNodeChildrenRemoved(SHEventPtr eventPtr)
+  {
+    auto eventData = reinterpret_cast<const SHEventSpec<SHSceneGraphRemoveChildEvent>*>(eventPtr.get());
+    csSceneNodeChildrenChanged(eventData->data->parent->GetEntityID());
+    return eventData->handle;
+  }
+
   /*-----------------------------------------------------------------------------------*/
   /* Helper Functions                                                                  */
   /*-----------------------------------------------------------------------------------*/
@@ -442,6 +456,12 @@ namespace SHADE
       DEFAULT_CSHARP_NAMESPACE + ".Collider",
       "OnCollisionShapeRemoved"
     );
+    csSceneNodeChildrenChanged = dotNet.GetFunctionPtr<CsEventRelayFuncPtr>
+    (
+      DEFAULT_CSHARP_LIB_NAME,
+      DEFAULT_CSHARP_NAMESPACE + ".ChildListCache",
+      "OnChildrenChanged"
+    );
     csEditorRenderScripts = dotNet.GetFunctionPtr<CsScriptEditorFuncPtr>
     (
       DEFAULT_CSHARP_LIB_NAME,
@@ -464,6 +484,7 @@ namespace SHADE
 
   void SHScriptEngine::registerEvents()
   {
+    /* Entity */
     // Register for entity destroyed event
     std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> destroyedEventReceiver
     {
@@ -471,26 +492,39 @@ namespace SHADE
     };
     SHEventManager::SubscribeTo(SH_ENTITY_DESTROYED_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(destroyedEventReceiver));
 
+    /* Colliders */
     // Register for collider added event
     std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> addedColliderEventReceiver
     {
       std::make_shared<SHEventReceiverSpec<SHScriptEngine>>(this, &SHScriptEngine::onColliderAdded)
     };
     SHEventManager::SubscribeTo(SH_PHYSICS_COLLIDER_ADDED_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(addedColliderEventReceiver));
-
     // Register for collider removed event
     std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> removedColliderEventReceiver
     {
       std::make_shared<SHEventReceiverSpec<SHScriptEngine>>(this, &SHScriptEngine::onColliderRemoved)
     };
     SHEventManager::SubscribeTo(SH_PHYSICS_COLLIDER_REMOVED_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(removedColliderEventReceiver));
-
     // Register for collider component removed event
     std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> removedColliderComponentEventReceiver
     {
       std::make_shared<SHEventReceiverSpec<SHScriptEngine>>(this, &SHScriptEngine::onColliderComponentRemoved)
     };
     SHEventManager::SubscribeTo(SH_COMPONENT_REMOVED_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(removedColliderComponentEventReceiver));
+
+    /* SceneGraph */
+    // Register for SceneNode child added event
+    std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> addChildEventReceiver
+    {
+      std::make_shared<SHEventReceiverSpec<SHScriptEngine>>(this, &SHScriptEngine::onSceneNodeChildrenAdded)
+    };
+    SHEventManager::SubscribeTo(SH_SCENEGRAPH_ADD_CHILD_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(addChildEventReceiver));
+    // Register for SceneNode child removed event
+    std::shared_ptr<SHEventReceiverSpec<SHScriptEngine>> removeChildEventReceiver
+    {
+      std::make_shared<SHEventReceiverSpec<SHScriptEngine>>(this, &SHScriptEngine::onSceneNodeChildrenRemoved)
+    };
+    SHEventManager::SubscribeTo(SH_SCENEGRAPH_REMOVE_CHILD_EVENT, std::dynamic_pointer_cast<SHEventReceiver>(removeChildEventReceiver));
   }
 
   void SHScriptEngine::dumpBuildLog(const std::string_view& buildLogPath)
diff --git a/SHADE_Engine/src/Scripting/SHScriptEngine.h b/SHADE_Engine/src/Scripting/SHScriptEngine.h
index 7d83606e..ef778627 100644
--- a/SHADE_Engine/src/Scripting/SHScriptEngine.h
+++ b/SHADE_Engine/src/Scripting/SHScriptEngine.h
@@ -267,6 +267,7 @@ namespace SHADE
     // - Events
     CsEventRelayFuncPtr            csColliderOnListChanged       = nullptr;
     CsEventRelayFuncPtr            csColliderOnRemoved           = nullptr;
+    CsEventRelayFuncPtr            csSceneNodeChildrenChanged    = nullptr;
     // - Editor
     CsScriptEditorFuncPtr          csEditorRenderScripts         = nullptr;
     CsFuncPtr                      csEditorUndo                  = nullptr;
@@ -279,6 +280,8 @@ namespace SHADE
     SHEventHandle onColliderAdded(SHEventPtr eventPtr);
     SHEventHandle onColliderRemoved(SHEventPtr eventPtr);
     SHEventHandle onColliderComponentRemoved(SHEventPtr eventPtr);
+    SHEventHandle onSceneNodeChildrenAdded(SHEventPtr eventPtr);
+    SHEventHandle onSceneNodeChildrenRemoved(SHEventPtr eventPtr);
 
     /*-----------------------------------------------------------------------------*/
     /* Helper Functions                                                            */
diff --git a/SHADE_Managed/src/Engine/GameObject.cxx b/SHADE_Managed/src/Engine/GameObject.cxx
index 79960ff6..017366fe 100644
--- a/SHADE_Managed/src/Engine/GameObject.cxx
+++ b/SHADE_Managed/src/Engine/GameObject.cxx
@@ -244,8 +244,7 @@ namespace SHADE
         // Unparent all children to the root
         for (auto child : node->GetChildren())
         {
-            child->SetParent(nullptr);
-            ChildListCache::UpdateChildList(child->GetEntityID());
+            SHSceneManager::GetCurrentSceneGraph().SetParent(child->GetEntityID(), nullptr);
         }
         ChildListCache::UpdateChildList(entity);
     }