From 0693ac1ad0ab2be1a26617c2bd24549a6fc37863 Mon Sep 17 00:00:00 2001
From: Antoine Pilote <antoinepilote1@hotmail.com>
Date: Mon, 1 Apr 2024 13:19:33 -0400
Subject: [PATCH] Added collision callback thread safe queue

---
 Nuake/src/Physics/DynamicWorld.cpp        | 22 ++++++++++++--
 Nuake/src/Physics/DynamicWorld.h          | 12 ++++++++
 Nuake/src/Scene/Systems/PhysicsSystem.cpp | 37 -----------------------
 3 files changed, 32 insertions(+), 39 deletions(-)

diff --git a/Nuake/src/Physics/DynamicWorld.cpp b/Nuake/src/Physics/DynamicWorld.cpp
index 596c634e..24336592 100644
--- a/Nuake/src/Physics/DynamicWorld.cpp
+++ b/Nuake/src/Physics/DynamicWorld.cpp
@@ -124,7 +124,15 @@ namespace Nuake
 	// An example contact listener
 	class MyContactListener : public JPH::ContactListener
 	{
+	private:
+		Physics::DynamicWorld* _World;
+
 	public:
+		MyContactListener(Physics::DynamicWorld* world)
+			: _World(world)
+		{
+		}
+
 		// See: ContactListener
 		virtual JPH::ValidateResult	OnContactValidate(const JPH::Body& inBody1, const JPH::Body& inBody2, JPH::RVec3Arg inBaseOffset, const JPH::CollideShapeResult& inCollisionResult) override
 		{
@@ -146,6 +154,9 @@ namespace Nuake
 			const std::string entity2Name = entity2.GetComponent<NameComponent>().Name;
 
 			Logger::Log("Collision detected between " + entity1Name + " and " + entity2Name);
+
+			Physics::CollisionCallbackData data;
+			_World->RegisterCollisionCallback(std::move(data));
 		}
 
 		virtual void OnContactPersisted(const JPH::Body& inBody1, const JPH::Body& inBody2, const JPH::ContactManifold& inManifold, JPH::ContactSettings& ioSettings) override
@@ -217,7 +228,6 @@ namespace Nuake
 		}
 	};
 
-
 	BPLayerInterfaceImpl JoltBroadphaseLayerInterface = BPLayerInterfaceImpl();
 	ObjectVsBroadPhaseLayerFilterImpl JoltObjectVSBroadphaseLayerFilter = ObjectVsBroadPhaseLayerFilterImpl();
 	ObjectLayerPairFilterImpl JoltObjectVSObjectLayerFilter;
@@ -246,7 +256,7 @@ namespace Nuake
 			// A contact listener gets notified when bodies (are about to) collide, and when they separate again.
 			// Note that this is called from a job so whatever you do here needs to be thread safe.
 			// Registering one is entirely optional.
-			_contactListener = CreateScope<MyContactListener>();
+			_contactListener = CreateScope<MyContactListener>(this);
 			_JoltPhysicsSystem->SetContactListener(_contactListener.get());
 
 			// The main way to interact with the bodies in the physics system is through the body interface. There is a locking and a non-locking
@@ -667,6 +677,14 @@ namespace Nuake
 			}
 		}
 
+		void DynamicWorld::RegisterCollisionCallback(const CollisionCallbackData& data)
+		{
+			// This will be called from multiple threads
+			std::scoped_lock<std::mutex> lock(_CollisionCallbackMutex); 
+
+			_CollisionCallbacks.push_back(std::move(data));
+		}
+
 		void DynamicWorld::MoveAndSlideCharacterController(const Entity& entity, const Vector3& velocity)
 		{
 			const uint32_t entityHandle = entity.GetHandle();
diff --git a/Nuake/src/Physics/DynamicWorld.h b/Nuake/src/Physics/DynamicWorld.h
index 78226b9e..5a7b13ae 100644
--- a/Nuake/src/Physics/DynamicWorld.h
+++ b/Nuake/src/Physics/DynamicWorld.h
@@ -41,6 +41,14 @@ namespace Nuake
 			uint32_t Ghost;
 		};
 
+		struct CollisionCallbackData
+		{
+			uint32_t Entity1;
+			uint32_t Entity2;
+			Vector3 Normal;
+			Vector3 Position;
+		};
+
 		class DynamicWorld 
 		{
 		private:
@@ -56,6 +64,8 @@ namespace Nuake
 			std::vector<uint32_t> _registeredBodies;
 			std::map<uint32_t, CharacterGhostPair> _registeredCharacters;
 
+			std::mutex _CollisionCallbackMutex;
+			std::vector<CollisionCallbackData> _CollisionCallbacks;
 		public:
 			DynamicWorld();
 
@@ -75,6 +85,8 @@ namespace Nuake
 			void StepSimulation(Timestep ts);
 			void Clear();
 
+			void RegisterCollisionCallback(const CollisionCallbackData& data);
+
 		private:
 			JPH::Ref<JPH::Shape> GetJoltShape(const Ref<PhysicShape> shape);
 			void SyncEntitiesTranforms();
diff --git a/Nuake/src/Scene/Systems/PhysicsSystem.cpp b/Nuake/src/Scene/Systems/PhysicsSystem.cpp
index bb54d874..3988b325 100644
--- a/Nuake/src/Scene/Systems/PhysicsSystem.cpp
+++ b/Nuake/src/Scene/Systems/PhysicsSystem.cpp
@@ -52,12 +52,6 @@ namespace Nuake
 		{
 			auto [transform, brush] = brushes.get<TransformComponent, BSPBrushComponent>(e);
 
-			for (auto& r : brush.Rigidbody)
-			{
-				//r->m_Transform->setOrigin(btVector3(transform.GlobalTranslation.x, transform.GlobalTranslation.y, transform.GlobalTranslation.z));
-				//r->UpdateTransform(*r->m_Transform);
-			}
-
 			if (!brush.IsFunc)
 				continue;
 
@@ -73,37 +67,6 @@ namespace Nuake
 				}
 			}
 		}
-
-		//auto bspTriggerView = m_Scene->m_Registry.view<TransformComponent, BSPBrushComponent, TriggerZone>();
-		//for (auto e : bspTriggerView)
-		//{
-		//	auto [transform, brush, trigger] = bspTriggerView.get<TransformComponent, BSPBrushComponent, TriggerZone>(e);
-		//	trigger.GhostObject->ScanOverlap();
-
-		//	brush.Targets.clear();
-		//	auto targetnameView = m_Scene->m_Registry.view<TransformComponent, NameComponent>();
-		//	for (auto e2 : targetnameView)
-		//	{
-		//		auto [ttransform, name] = targetnameView.get<TransformComponent, NameComponent>(e2);
-
-		//		if (name.Name == brush.target) {
-		//			brush.Targets.push_back(Entity{ e2, m_Scene });
-		//		}
-		//	}
-		//}
-
-
-		/*auto physicGroup = m_Scene->m_Registry.view<TransformComponent, RigidBodyComponent>();
-		for (auto e : physicGroup) {
-			auto [transform, rb] = physicGroup.get<TransformComponent, RigidBodyComponent>(e);
-			rb.SyncTransformComponent(&m_Scene->m_Registry.get<TransformComponent>(e));
-		}*/
-
-		//auto ccGroup = m_Scene->m_Registry.view<TransformComponent, CharacterControllerComponent>();
-		//for (auto e : ccGroup) {
-		//	auto [transform, rb] = ccGroup.get<TransformComponent, CharacterControllerComponent>(e);
-		//	rb.SyncWithTransform(m_Scene->m_Registry.get<TransformComponent>(e));
-		//}
 	}
 
 	void PhysicsSystem::FixedUpdate(Timestep ts)