From de7c6483e0236a7a15bd4fad97c079d17a6ecccc Mon Sep 17 00:00:00 2001
From: Ari Vuollet <ari.vuollet@kapsi.fi>
Date: Thu, 11 May 2023 21:09:33 +0300
Subject: [PATCH] Add LateFixedUpdate event for C# scripts

---
 Source/Engine/Level/Scene/SceneTicking.cpp | 19 +++++++++++++++++++
 Source/Engine/Level/Scene/SceneTicking.h   | 12 ++++++++++++
 Source/Engine/Scripting/Script.cpp         |  2 ++
 Source/Engine/Scripting/Script.h           |  1 +
 4 files changed, 34 insertions(+)

diff --git a/Source/Engine/Level/Scene/SceneTicking.cpp b/Source/Engine/Level/Scene/SceneTicking.cpp
index 8998a4b37..7aeee452b 100644
--- a/Source/Engine/Level/Scene/SceneTicking.cpp
+++ b/Source/Engine/Level/Scene/SceneTicking.cpp
@@ -121,6 +121,19 @@ void SceneTicking::LateUpdateTickData::TickScripts(const Array<Script*>& scripts
     }
 }
 
+SceneTicking::LateFixedUpdateTickData::LateFixedUpdateTickData()
+    : TickData(64)
+{
+}
+
+void SceneTicking::LateFixedUpdateTickData::TickScripts(const Array<Script*>& scripts)
+{
+    for (auto* script : scripts)
+    {
+        script->OnLateFixedUpdate();
+    }
+}
+
 void SceneTicking::AddScript(Script* obj)
 {
     ASSERT_LOW_LAYER(obj && obj->GetParent() && obj->GetParent()->GetScene());
@@ -130,6 +143,9 @@ void SceneTicking::AddScript(Script* obj)
         Update.AddScript(obj);
     if (obj->_tickLateUpdate)
         LateUpdate.AddScript(obj);
+    if (obj->_tickLateFixedUpdate)
+        LateFixedUpdate.AddScript(obj);
+    
 }
 
 void SceneTicking::RemoveScript(Script* obj)
@@ -141,6 +157,8 @@ void SceneTicking::RemoveScript(Script* obj)
         Update.RemoveScript(obj);
     if (obj->_tickLateUpdate)
         LateUpdate.RemoveScript(obj);
+    if (obj->_tickLateFixedUpdate)
+        LateFixedUpdate.RemoveScript(obj);
 }
 
 void SceneTicking::Clear()
@@ -148,4 +166,5 @@ void SceneTicking::Clear()
     FixedUpdate.Clear();
     Update.Clear();
     LateUpdate.Clear();
+    LateFixedUpdate.Clear();
 }
diff --git a/Source/Engine/Level/Scene/SceneTicking.h b/Source/Engine/Level/Scene/SceneTicking.h
index 230861087..7d590c8e7 100644
--- a/Source/Engine/Level/Scene/SceneTicking.h
+++ b/Source/Engine/Level/Scene/SceneTicking.h
@@ -109,6 +109,13 @@ public:
         void TickScripts(const Array<Script*>& scripts) override;
     };
 
+    class FLAXENGINE_API LateFixedUpdateTickData : public TickData
+    {
+    public:
+        LateFixedUpdateTickData();
+        void TickScripts(const Array<Script*>& scripts) override;
+    };
+
 public:
     /// <summary>
     /// Adds the script to scene ticking system.
@@ -142,4 +149,9 @@ public:
     /// The late update tick function.
     /// </summary>
     LateUpdateTickData LateUpdate;
+
+    /// <summary>
+    /// The late fixed update tick function.
+    /// </summary>
+    LateFixedUpdateTickData LateFixedUpdate;
 };
diff --git a/Source/Engine/Scripting/Script.cpp b/Source/Engine/Scripting/Script.cpp
index 3f8df354c..8eaff42de 100644
--- a/Source/Engine/Scripting/Script.cpp
+++ b/Source/Engine/Scripting/Script.cpp
@@ -26,6 +26,7 @@ Script::Script(const SpawnParams& params)
     , _tickFixedUpdate(false)
     , _tickUpdate(false)
     , _tickLateUpdate(false)
+    , _tickLateFixedUpdate(false)
     , _wasStartCalled(false)
     , _wasEnableCalled(false)
 {
@@ -181,6 +182,7 @@ void Script::SetupType()
             _tickUpdate |= type.Script.ScriptVTable[8] != nullptr;
             _tickLateUpdate |= type.Script.ScriptVTable[9] != nullptr;
             _tickFixedUpdate |= type.Script.ScriptVTable[10] != nullptr;
+            _tickLateFixedUpdate |= type.Script.ScriptVTable[11] != nullptr;
         }
         typeHandle = type.GetBaseType();
     }
diff --git a/Source/Engine/Scripting/Script.h b/Source/Engine/Scripting/Script.h
index 769771f46..49cba0ec4 100644
--- a/Source/Engine/Scripting/Script.h
+++ b/Source/Engine/Scripting/Script.h
@@ -19,6 +19,7 @@ protected:
     int32 _tickFixedUpdate : 1;
     int32 _tickUpdate : 1;
     int32 _tickLateUpdate : 1;
+    int32 _tickLateFixedUpdate : 1;
     int32 _wasStartCalled : 1;
     int32 _wasEnableCalled : 1;
 #if USE_EDITOR