Added the ability to look up a Net Entity ID for a given AZ Entity ID

Signed-off-by: pereslav <pereslav@amazon.com>

Gems/Multiplayer/Code/Include/Multiplayer/NetworkEntity/INetworkEntityManager.h

@@ -89,6 +89,11 @@ namespace Multiplayer
         //! @return the total number of entities tracked by this INetworkEntityManager instance
         virtual uint32_t GetEntityCount() const = 0;
 
+        //! Returns the Net Entity ID for a given AZ Entity ID.
+        //! @param entityId the AZ Entity ID
+        //! @return the Net Entity ID
+        virtual NetEntityId GetNetEntityIdById(const AZ::EntityId& entityId) const = 0;
+
         //! Adds the provided entity to the internal entity map identified by the provided netEntityId.
         //! @param netEntityId the identifier to use for the added entity
         //! @param entity      the entity to add to the internal entity map

Gems/Multiplayer/Code/Source/NetworkEntity/NetworkEntityManager.cpp

@@ -73,6 +73,11 @@ namespace Multiplayer
         return m_networkEntityTracker.Get(netEntityId);
     }
 
+    NetEntityId NetworkEntityManager::GetNetEntityIdById(const AZ::EntityId& entityId) const
+    {
+        return m_networkEntityTracker.Get(entityId);
+    }
+
     uint32_t NetworkEntityManager::GetEntityCount() const
     {
         return static_cast<uint32_t>(m_networkEntityTracker.size());

Gems/Multiplayer/Code/Source/NetworkEntity/NetworkEntityManager.h

@@ -41,6 +41,7 @@ namespace Multiplayer
         MultiplayerComponentRegistry* GetMultiplayerComponentRegistry() override;
         HostId GetHostId() const override;
         ConstNetworkEntityHandle GetEntity(NetEntityId netEntityId) const override;
+        NetEntityId GetNetEntityIdById(const AZ::EntityId& entityId) const override;
 
         EntityList CreateEntitiesImmediate(const AzFramework::Spawnable& spawnable, NetEntityRole netEntityRole);
         EntityList CreateEntitiesImmediate

Gems/Multiplayer/Code/Source/NetworkEntity/NetworkEntityTracker.cpp

@@ -18,6 +18,7 @@ namespace Multiplayer
         ++m_addChangeDirty;
         AZ_Assert(m_entityMap.end() == m_entityMap.find(netEntityId), "Attempting to add the same entity to the entity map multiple times");
         m_entityMap[netEntityId] = entity;
+        m_netEntityIdMap[entity->GetId()] = netEntityId;
     }
 
     NetworkEntityHandle NetworkEntityTracker::Get(NetEntityId netEntityId)
@@ -32,6 +33,16 @@ namespace Multiplayer
         return ConstNetworkEntityHandle(entity, netEntityId, this);
     }
 
+    NetEntityId NetworkEntityTracker::Get(const AZ::EntityId& entityId) const
+    {
+        auto found = m_netEntityIdMap.find(entityId);
+        if (found != m_netEntityIdMap.end())
+        {
+            return found->second;
+        }
+        return Multiplayer::InvalidNetEntityId;
+    }
+
     bool NetworkEntityTracker::Exists(NetEntityId netEntityId) const
     {
         return (m_entityMap.find(netEntityId) != m_entityMap.end());
@@ -50,12 +61,22 @@ namespace Multiplayer
     void NetworkEntityTracker::erase(NetEntityId netEntityId)
     {
         ++m_deleteChangeDirty;
-        m_entityMap.erase(netEntityId);
+
+        auto found = m_entityMap.find(netEntityId);
+        if (found != m_entityMap.end())
+        {
+            m_netEntityIdMap.erase(found->second->GetId());            
+            m_entityMap.erase(found);
+        }
     }
 
     NetworkEntityTracker::EntityMap::iterator NetworkEntityTracker::erase(EntityMap::iterator iter)
     {
         ++m_deleteChangeDirty;
+        if (iter != m_entityMap.end())
+        {
+            m_netEntityIdMap.erase(iter->second->GetId());
+        }
         return m_entityMap.erase(iter);
     }
 

Gems/Multiplayer/Code/Source/NetworkEntity/NetworkEntityTracker.h

@@ -22,6 +22,7 @@ namespace Multiplayer
     public:
 
         using EntityMap = AZStd::unordered_map<NetEntityId, AZ::Entity*>;
+        using NetEntityIdMap = AZStd::unordered_map<AZ::EntityId, NetEntityId>;
         using iterator = EntityMap::iterator;
         using const_iterator = EntityMap::const_iterator;
 
@@ -36,6 +37,8 @@ namespace Multiplayer
         NetworkEntityHandle Get(NetEntityId netEntityId);
         ConstNetworkEntityHandle Get(NetEntityId netEntityId) const;
 
+        NetEntityId Get(const AZ::EntityId& entityId) const;
+
         //! Returns true if the netEntityId exists.
         bool Exists(NetEntityId netEntityId) const;
 
@@ -74,6 +77,7 @@ namespace Multiplayer
     private:
 
         EntityMap m_entityMap;
+        NetEntityIdMap m_netEntityIdMap;
         uint32_t m_deleteChangeDirty = 0;
         uint32_t m_addChangeDirty = 0;
     };

Gems/Multiplayer/Code/Source/NetworkEntity/NetworkEntityTracker.inl

@@ -48,6 +48,7 @@ namespace Multiplayer
     inline void NetworkEntityTracker::clear()
     {
         m_entityMap.clear();
+        m_netEntityIdMap.clear();
     }
 
     inline uint32_t NetworkEntityTracker::GetChangeDirty(const AZ::Entity* entity) const