Hierarchical components, phase 1, unittests

Signed-off-by: AMZN-Olex <5432499+AMZN-Olex@users.noreply.github.com>

Gems/Multiplayer/Code/Include/Multiplayer/Components/NetBindComponent.h

@@ -199,6 +199,8 @@ namespace Multiplayer
 
         friend class NetworkEntityManager;
         friend class EntityReplicationManager;
+
+        friend class HierarchyTests;
     };
 
     bool NetworkRoleHasController(NetEntityRole networkRole);

Gems/Multiplayer/Code/Include/Multiplayer/Components/NetworkHierarchyBus.h

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+
+#pragma once
+
+#include <AzCore/Component/ComponentBus.h>
+
+namespace Multiplayer
+{
+    class NetworkHierarchyNotifications
+        : public AZ::ComponentBus
+    {
+    public:
+        //! Called when a hierarchy has been updated (a child added or removed, etc.)
+        virtual void OnNetworkHierarchyUpdated([[maybe_unused]] const AZ::EntityId& rootEntityId) {}
+
+        //! Called when an entity has left a hierarchy
+        virtual void OnLeavingNetworkHierarchy() {}
+    };
+
+    typedef AZ::EBus<NetworkHierarchyNotifications> NetworkHierarchyNotificationBus;
+
+    class NetworkHierarchyRequests
+        : public AZ::ComponentBus
+    {
+    public:
+        //! @returns hierarchical entities, the first element is the top level root
+        virtual AZStd::vector<AZ::Entity*> GetHierarchicalEntities() const = 0;
+
+        //! @returns the top level root of a hierarchy, or nullptr if this entity is not in a hierarchy
+        virtual AZ::Entity* GetHierarchicalRoot() const = 0;
+
+        //! @return true if this entity is a child entity within a hierarchy
+        virtual bool IsHierarchicalChild() const = 0;
+
+        //! @return true if this entity is the top level root of a hierarchy
+        virtual bool IsHierarchicalRoot() const = 0;
+    };
+
+    typedef AZ::EBus<NetworkHierarchyRequests> NetworkHierarchyRequestBus;
+}

Gems/Multiplayer/Code/Include/Multiplayer/Components/NetworkHierarchyChildComponent.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+
+#pragma once
+
+#include <AzCore/Component/Component.h>
+#include <Multiplayer/Components/NetworkHierarchyBus.h>
+#include <Source/AutoGen/NetworkHierarchyChildComponent.AutoComponent.h>
+
+namespace Multiplayer
+{
+    class NetworkHierarchyRootComponent;
+
+    //! @class NetworkHierarchyChildComponent
+    //! @brief Component that declares network dependency on the parent of this entity
+    /*
+     * The parent of this entity should have @NetworkHierarchyChildComponent (or @NetworkHierarchyRootComponent).
+     * A network hierarchy is a collection of entities with one @NetworkHierarchyRootComponent at the top parent
+     * and one or more @NetworkHierarchyChildComponent on its child entities.
+     */
+    class NetworkHierarchyChildComponent final
+        : public NetworkHierarchyChildComponentBase
+        , public NetworkHierarchyRequestBus::Handler
+    {
+        friend class NetworkHierarchyRootComponent;
+
+    public:
+        AZ_MULTIPLAYER_COMPONENT(Multiplayer::NetworkHierarchyChildComponent, s_networkHierarchyChildComponentConcreteUuid, Multiplayer::NetworkHierarchyChildComponentBase);
+
+        static void Reflect(AZ::ReflectContext* context);
+        static void GetRequiredServices(AZ::ComponentDescriptor::DependencyArrayType& required);
+        static void GetProvidedServices(AZ::ComponentDescriptor::DependencyArrayType& provided);
+        static void GetIncompatibleServices(AZ::ComponentDescriptor::DependencyArrayType& incompatible);
+
+        NetworkHierarchyChildComponent();
+
+        //! @{
+        void OnInit() override;
+        void OnActivate(Multiplayer::EntityIsMigrating entityIsMigrating) override;
+        void OnDeactivate(Multiplayer::EntityIsMigrating entityIsMigrating) override;
+        //! @}
+
+        //! NetworkHierarchyRequestBus overrides
+        //! @{
+        bool IsHierarchicalChild() const override;
+        bool IsHierarchicalRoot() const override { return false; }
+        AZ::Entity* GetHierarchicalRoot() const override;
+        AZStd::vector<AZ::Entity*> GetHierarchicalEntities() const override;
+        //! @}
+
+    protected:
+        //! Used by @NetworkHierarchyRootComponent
+        void SetTopLevelHierarchyRootComponent(NetworkHierarchyRootComponent* hierarchyRoot);
+
+    private:
+        const NetworkHierarchyRootComponent* m_hierarchyRootComponent = nullptr;
+
+        AZ::Event<NetEntityId>::Handler m_hierarchyRootNetIdChanged;
+        void OnHierarchyRootNetIdChanged(NetEntityId rootNetId);
+    };
+}

Gems/Multiplayer/Code/Include/Multiplayer/Components/NetworkHierarchyRootComponent.h

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+
+#pragma once
+
+#include <AzCore/Component/Component.h>
+#include <AzCore/Component/TransformBus.h>
+#include <Source/AutoGen/NetworkHierarchyRootComponent.AutoComponent.h>
+#include <Multiplayer/Components/NetworkHierarchyBus.h>
+
+namespace Multiplayer
+{
+    //! @class NetworkHierarchyRootComponent
+    //! @brief Component that declares the top level entity of a network hierarchy.
+    /*
+     * Call @GetHierarchyChildren to get the list of hierarchical entities.
+     * A network hierarchy is meant to be a small group of entities. You can control the maximum supported size of
+     * a network hierarchy by modifying CVar @bg_hierarchyEntityMaxLimit.
+     *
+     * A root component marks either a top most root of a hierarchy, or an inner root of an attach hierarchy.
+     */
+    class NetworkHierarchyRootComponent final
+        : public NetworkHierarchyRootComponentBase
+        , public NetworkHierarchyRequestBus::Handler
+        , protected AZ::TransformNotificationBus::MultiHandler
+    {
+    public:
+        AZ_MULTIPLAYER_COMPONENT(Multiplayer::NetworkHierarchyRootComponent, s_networkHierarchyRootComponentConcreteUuid, Multiplayer::NetworkHierarchyRootComponentBase);
+
+        static void Reflect(AZ::ReflectContext* context);
+        static void GetRequiredServices(AZ::ComponentDescriptor::DependencyArrayType& required);
+        static void GetProvidedServices(AZ::ComponentDescriptor::DependencyArrayType& provided);
+        static void GetIncompatibleServices(AZ::ComponentDescriptor::DependencyArrayType& incompatible);
+
+        //! NetworkHierarchyRootComponentBase overrides.
+        //! @{
+        void OnInit() override;
+        void OnActivate(Multiplayer::EntityIsMigrating entityIsMigrating) override;
+        void OnDeactivate(Multiplayer::EntityIsMigrating entityIsMigrating) override;
+        //! @}
+
+        //! NetworkHierarchyRequestBus overrides.
+        //! @{
+        bool IsHierarchicalRoot() const override;
+        bool IsHierarchicalChild() const override;
+        AZStd::vector<AZ::Entity*> GetHierarchicalEntities() const override;
+        AZ::Entity* GetHierarchicalRoot() const override;
+        //! @}
+
+    protected:
+        //! AZ::TransformNotificationBus::Handler overrides.
+        //! @{
+        void OnParentChanged(AZ::EntityId oldParent, AZ::EntityId newParent) override;
+        void OnChildAdded(AZ::EntityId child) override;
+        void OnChildRemoved(AZ::EntityId childRemovedId) override;
+        //! @}
+
+        void SetTopLevelHierarchyRootEntity(AZ::Entity* hierarchyRoot);
+
+    private:
+        AZ::Entity* m_higherRootEntity = nullptr;
+        AZStd::vector<AZ::Entity*> m_hierarchicalEntities;
+
+        void RebuildHierarchy();
+
+        //! @returns false if the maximum supported hierarchy size has been reached
+        bool RecursiveAttachHierarchicalEntities(AZ::EntityId underEntity, uint32_t& currentEntityCount);
+        //! @returns false if the maximum supported hierarchy size has been reached
+        bool RecursiveAttachHierarchicalChild(AZ::EntityId entity, uint32_t& currentEntityCount);
+    };
+}

Gems/Multiplayer/Code/Include/Multiplayer/Components/NetworkTransformComponent.h

@@ -36,6 +36,7 @@ namespace Multiplayer
         void OnTranslationChangedEvent(const AZ::Vector3& translation);
         void OnScaleChangedEvent(float scale);
         void OnResetCountChangedEvent();
+        void OnParentIdChangedEvent(NetEntityId newParent);
 
         void UpdateTargetHostFrameId();
 
@@ -46,6 +47,7 @@ namespace Multiplayer
         AZ::Event<AZ::Vector3>::Handler m_translationEventHandler;
         AZ::Event<float>::Handler m_scaleEventHandler;
         AZ::Event<uint8_t>::Handler m_resetCountEventHandler;
+        AZ::Event<NetEntityId>::Handler m_parentIdChangedEventHandler;
 
         EntityPreRenderEvent::Handler m_entityPreRenderEventHandler;
         EntityCorrectionEvent::Handler m_entityCorrectionEventHandler;
@@ -64,7 +66,9 @@ namespace Multiplayer
 
     private:
         void OnTransformChangedEvent(const AZ::Transform& worldTm);
+        void OnParentIdChangedEvent(AZ::EntityId oldParent, AZ::EntityId newParent);
 
         AZ::TransformChangedEvent::Handler m_transformChangedHandler;
+        AZ::ParentChangedEvent::Handler m_parentIdChangedHandler;
     };
 }