From 360f498e47c074cf68df4340e31cb813c071ffad Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Sat, 12 Jun 2021 22:44:16 +0200
Subject: [PATCH] Add `Engine::UpdateGraph` for async engine/game update

---
 Source/Engine/Engine/Engine.cpp | 5 +++++
 Source/Engine/Engine/Engine.h   | 6 ++++++
 2 files changed, 11 insertions(+)

diff --git a/Source/Engine/Engine/Engine.cpp b/Source/Engine/Engine/Engine.cpp
index a5fd460fb..bfa2338c6 100644
--- a/Source/Engine/Engine/Engine.cpp
+++ b/Source/Engine/Engine/Engine.cpp
@@ -27,6 +27,7 @@
 #include "Engine/Graphics/RenderTargetPool.h"
 #include "Engine/Graphics/RenderTask.h"
 #include "Engine/Profiler/Profiler.h"
+#include "Engine/Threading/TaskGraph.h"
 #if USE_EDITOR
 #include "Editor/Editor.h"
 #include "Editor/ProjectInfo.h"
@@ -62,6 +63,7 @@ bool Engine::HasFocus = false;
 uint64 Engine::FrameCount = 0;
 Action Engine::FixedUpdate;
 Action Engine::Update;
+TaskGraph* Engine::UpdateGraph = nullptr;
 Action Engine::LateUpdate;
 Action Engine::Draw;
 Action Engine::Pause;
@@ -122,6 +124,7 @@ int32 Engine::Main(const Char* cmdLine)
 #endif
 
     // Initialize engine
+    UpdateGraph = New<TaskGraph>();
     EngineService::OnInit();
     if (Application::Init())
         return -10;
@@ -289,6 +292,7 @@ void Engine::OnUpdate()
 
     // Call event
     Update();
+    UpdateGraph->Execute();
 
     // Update services
     EngineService::OnUpdate();
@@ -436,6 +440,7 @@ void Engine::OnExit()
 
     // Unload Engine services
     EngineService::OnDispose();
+    Delete(UpdateGraph);
 
     LOG_FLUSH();
 
diff --git a/Source/Engine/Engine/Engine.h b/Source/Engine/Engine/Engine.h
index 13f3e1fe8..51860e5a2 100644
--- a/Source/Engine/Engine/Engine.h
+++ b/Source/Engine/Engine/Engine.h
@@ -6,6 +6,7 @@
 #include "Engine/Core/Types/DateTime.h"
 #include "Engine/Scripting/ScriptingType.h"
 
+class TaskGraph;
 class JsonAsset;
 
 /// <summary>
@@ -43,6 +44,11 @@ public:
     /// </summary>
     static Action Update;
 
+    /// <summary>
+    /// Task graph for engine update.
+    /// </summary>
+    API_FIELD(ReadOnly) static TaskGraph* UpdateGraph;
+
     /// <summary>
     /// Event called after engine update.
     /// </summary>