physics: parented rigid body is detached only temporarlily during simulation to not modify real hierarchy system

WickedEngine/wiPhysics_Jolt.cpp

@@ -240,6 +240,10 @@ namespace wi::physics
 			BodyID bodyID;
 			Entity entity = INVALID_ENTITY;
 
+			// Things for parented objects:
+			XMFLOAT4X4 parentMatrix = wi::math::IDENTITY_MATRIX;
+			XMFLOAT4X4 parentMatrixInverse = wi::math::IDENTITY_MATRIX;
+
 			// Interpolation state:
 			Vec3 prev_position = Vec3::sZero();
 			Quat prev_rotation = Quat::sIdentity();
@@ -317,12 +321,21 @@ namespace wi::physics
 			wi::scene::Scene& scene,
 			Entity entity,
 			wi::scene::RigidBodyPhysicsComponent& physicscomponent,
-			const wi::scene::TransformComponent& transform,
+			const wi::scene::TransformComponent& _transform,
 			const wi::scene::MeshComponent* mesh
 		)
 		{
 			ShapeSettings::ShapeResult shape_result;
 
+			TransformComponent transform = _transform;
+
+			scene.locker.lock();
+			XMMATRIX parentMatrix = scene.ComputeParentMatrixRecursive(entity);
+			scene.locker.unlock();
+
+			XMStoreFloat4x4(&transform.world, parentMatrix * transform.GetLocalMatrix());
+			transform.ApplyTransform();
+
 			// The default convex radius caused issues when creating small box shape, etc, so I decrease it:
 			const float convexRadius = 0.001f;
 
@@ -422,6 +435,8 @@ namespace wi::physics
 				RigidBody& physicsobject = GetRigidBody(physicscomponent);
 				physicsobject.physics_scene = scene.physics_scene;
 				physicsobject.entity = entity;
+				XMStoreFloat4x4(&physicsobject.parentMatrix, parentMatrix);
+				XMStoreFloat4x4(&physicsobject.parentMatrixInverse, XMMatrixInverse(nullptr, parentMatrix));
 				PhysicsScene& physics_scene = GetPhysicsScene(scene);
 
 				physicsobject.shape = shape_result.Get();
@@ -471,15 +486,6 @@ namespace wi::physics
 					wi::backlog::post("AddRigidBody failed: body couldn't be created! This could mean that there are too many physics objects.", wi::backlog::LogLevel::Error);
 					return;
 				}
-
-				if (motionType == EMotionType::Dynamic)
-				{
-					// We must detach dynamic objects, because their physics object is created in world space
-					//	and attachment would apply double transformation to the transform
-					scene.locker.lock();
-					scene.Component_Detach(entity);
-					scene.locker.unlock();
-				}
 			}
 		}
 		void AddSoftBody(
@@ -1223,11 +1229,12 @@ namespace wi::physics
 
 					if (currentMotionType == EMotionType::Dynamic)
 					{
-						// We must detach dynamic objects, because their physics object is created in world space
-						//	and attachment would apply double transformation to the transform
+						// Changed to dynamic, remember attachment matrices at this point:
 						scene.locker.lock();
-						scene.Component_Detach(entity);
+						XMMATRIX parentMatrix = scene.ComputeParentMatrixRecursive(entity);
 						scene.locker.unlock();
+						XMStoreFloat4x4(&physicsobject.parentMatrix, parentMatrix);
+						XMStoreFloat4x4(&physicsobject.parentMatrixInverse, XMMatrixInverse(nullptr, parentMatrix));
 					}
 				}
 
@@ -1235,6 +1242,12 @@ namespace wi::physics
 				if (transform == nullptr)
 					return;
 
+				if (currentMotionType == EMotionType::Dynamic)
+				{
+					// Detaching object manually before the physics simulation:
+					transform->MatrixTransform(physicsobject.parentMatrix);
+				}
+
 				if (physics_scene.activate_all_rigid_bodies)
 				{
 					body_interface.ActivateBody(physicsobject.bodyID);
@@ -1596,7 +1609,9 @@ namespace wi::physics
 
 			transform->translation_local = cast(position);
 			transform->rotation_local = cast(rotation);
-			transform->SetDirty();
+
+			// Back to local space of parent:
+			transform->MatrixTransform(physicsobject.parentMatrixInverse);
 		});
 		
 		wi::jobsystem::Dispatch(ctx, (uint32_t)scene.softbodies.GetCount(), 1, [&scene, &physics_scene](wi::jobsystem::JobArgs args) {

WickedEngine/wiScene.cpp

@@ -7360,6 +7360,15 @@ namespace wi::scene
 	}
 
 
+	XMMATRIX Scene::ComputeEntityMatrixRecursive(wi::ecs::Entity entity) const
+	{
+		const TransformComponent* transform = transforms.GetComponent(entity);
+		if (transform == nullptr)
+			return XMMatrixIdentity();
+
+		return transform->GetLocalMatrix() * ComputeParentMatrixRecursive(entity);
+	}
+
 	XMMATRIX Scene::ComputeParentMatrixRecursive(Entity entity) const
 	{
 		XMMATRIX parentMatrix = XMMatrixIdentity();

WickedEngine/wiScene.h

@@ -528,6 +528,9 @@ namespace wi::scene
 		using CapsuleIntersectionResult = SphereIntersectionResult;
 		CapsuleIntersectionResult Intersects(const wi::primitive::Capsule& capsule, uint32_t filterMask = wi::enums::FILTER_OPAQUE, uint32_t layerMask = ~0, uint32_t lod = 0) const;
 
+		// Goes through the hierarchy backwards and computes entity's world space matrix:
+		XMMATRIX ComputeEntityMatrixRecursive(wi::ecs::Entity entity) const;
+
 		// Goes through the hierarchy backwards and computes parent's world space matrix:
 		XMMATRIX ComputeParentMatrixRecursive(wi::ecs::Entity entity) const;
 
@@ -542,7 +545,7 @@ namespace wi::scene
 		//	returns entity ID of the new animation or INVALID_ENTITY if retargeting was not successful
 		wi::ecs::Entity RetargetAnimation(wi::ecs::Entity dst, wi::ecs::Entity src, bool bake_data, const Scene* src_scene = nullptr);
 
-		// If you don't know which armature the bone is contained int, this function can be used to find the first such armature and return the bone's rest matrix
+		// If you don't know which armature the bone is contained in, this function can be used to find the first such armature and return the bone's rest matrix
 		//	If not found, and entity has a transform, it returns transform matrix
 		//	Otherwise, returns identity matrix
 		XMMATRIX GetRestPose(wi::ecs::Entity entity) const;

WickedEngine/wiVersion.cpp

@@ -9,7 +9,7 @@ namespace wi::version
 	// minor features, major updates, breaking compatibility changes
 	const int minor = 71;
 	// minor bug fixes, alterations, refactors, updates
-	const int revision = 662;
+	const int revision = 663;
 
 	const std::string version_string = std::to_string(major) + "." + std::to_string(minor) + "." + std::to_string(revision);