recover hotbar selected slot after reconnect (#4249)

1. implement protocol message SendHeldItemChange
2. add save / load inventory equipped item slot in JSON
3. send held item slot message after player connect to server

Fixes #4189

src/ClientHandle.cpp

@@ -417,6 +417,9 @@ void cClientHandle::FinishAuthenticate(const AString & a_Name, const cUUID & a_U
 		// Send experience
 		m_Player->SendExperience();
 
+		// Send hotbar active slot
+		m_Player->SendHotbarActiveSlot();
+
 		// Send player list items
 		SendPlayerListAddPlayer(*m_Player);
 		cRoot::Get()->BroadcastPlayerListsAddPlayer(*m_Player);
@@ -2635,6 +2638,15 @@ void cClientHandle::SendHealth(void)
 
 
 
+void cClientHandle::SendHeldItemChange(int a_ItemIndex)
+{
+	m_Protocol->SendHeldItemChange(a_ItemIndex);
+}
+
+
+
+
+
 void cClientHandle::SendHideTitle(void)
 {
 	m_Protocol->SendHideTitle();

src/ClientHandle.h

@@ -176,6 +176,7 @@ public:  // tolua_export
 	void SendExplosion                  (double a_BlockX, double a_BlockY, double a_BlockZ, float a_Radius, const cVector3iArray & a_BlocksAffected, const Vector3d & a_PlayerMotion);
 	void SendGameMode                   (eGameMode a_GameMode);
 	void SendHealth                     (void);
+	void SendHeldItemChange             (int a_ItemIndex);
 	void SendHideTitle                  (void);   // tolua_export
 	void SendInventorySlot              (char a_WindowID, short a_SlotNum, const cItem & a_Item);
 	void SendLeashEntity                (const cEntity & a_Entity, const cEntity & a_EntityLeashedTo);

src/Entities/Player.cpp

@@ -743,6 +743,18 @@ void cPlayer::SendHealth(void)
 
 
 
+void cPlayer::SendHotbarActiveSlot(void)
+{
+	if (m_ClientHandle != nullptr)
+	{
+		m_ClientHandle->SendHeldItemChange(m_Inventory.GetEquippedSlotNum());
+	}
+}
+
+
+
+
+
 void cPlayer::SendExperience(void)
 {
 	if (m_ClientHandle != nullptr)
@@ -2212,6 +2224,10 @@ bool cPlayer::LoadFromFile(const AString & a_FileName, cWorldPtr & a_World)
 	}
 
 	m_Inventory.LoadFromJson(root["inventory"]);
+
+	int equippedSlotNum = root.get("equippedItemSlot", 0).asInt();
+	m_Inventory.SetEquippedSlotNum(equippedSlotNum);
+
 	cEnderChestEntity::LoadFromJson(root["enderchestinventory"], m_EnderChestContents);
 
 	m_LoadedWorldName = root.get("world", "world").asString();
@@ -2302,6 +2318,7 @@ bool cPlayer::SaveToDisk()
 	root["position"]            = JSON_PlayerPosition;
 	root["rotation"]            = JSON_PlayerRotation;
 	root["inventory"]           = JSON_Inventory;
+	root["equippedItemSlot"]    = m_Inventory.GetEquippedSlotNum();
 	root["enderchestinventory"] = JSON_EnderChestInventory;
 	root["health"]              = m_Health;
 	root["xpTotal"]             = m_LifetimeTotalXp;

src/Entities/Player.h

@@ -431,6 +431,9 @@ public:
 
 	void SendHealth(void);
 
+	// Send current active hotbar slot
+	void SendHotbarActiveSlot(void);
+
 	void SendExperience(void);
 
 	/** In UI windows, get the item that the player is dragging */

src/Protocol/PacketID.cpp

@@ -41,6 +41,7 @@ UInt32 cProtocol_1_9_0::GetPacketId(eOutgoingPackets a_Packet)
 		case sendExplosion:             return 0x1c;
 		case sendGameMode:              return 0x1e;
 		case sendHealth:                return 0x3e;
+		case sendHeldItemChange:        return 0x37;
 		case sendInventorySlot:         return 0x16;
 		case sendJoinGame:              return 0x23;
 		case sendKeepAlive:             return 0x1f;
@@ -124,6 +125,7 @@ UInt32 cProtocol_1_12::GetPacketId(eOutgoingPackets a_Packet)
 		case sendEntityVelocity:      return 0x3d;
 		case sendExperience:          return 0x3f;
 		case sendHealth:              return 0x40;
+		case sendHeldItemChange:      return 0x39;
 		case sendLeashEntity:         return 0x3c;
 		case sendPlayerMaxSpeed:      return 0x4d;
 		case sendRemoveEntityEffect:  return 0x32;
@@ -161,6 +163,7 @@ UInt32 cProtocol_1_12_1::GetPacketId(eOutgoingPackets a_Packet)
 		case sendEntityVelocity:      return 0x3e;
 		case sendExperience:          return 0x40;
 		case sendHealth:              return 0x41;
+		case sendHeldItemChange:      return 0x3a;
 		case sendLeashEntity:         return 0x3d;
 		case sendPlayerList:          return 0x2e;
 		case sendPlayerAbilities:     return 0x2c;

src/Protocol/Protocol.h

@@ -89,6 +89,7 @@ public:
 		sendExplosion,
 		sendGameMode,
 		sendHealth,
+		sendHeldItemChange,
 		sendInventorySlot,
 		sendJoinGame,
 		sendKeepAlive,
@@ -160,6 +161,7 @@ public:
 	virtual void SendExplosion                  (double a_BlockX, double a_BlockY, double a_BlockZ, float a_Radius, const cVector3iArray & a_BlocksAffected, const Vector3d & a_PlayerMotion) = 0;
 	virtual void SendGameMode                   (eGameMode a_GameMode) = 0;
 	virtual void SendHealth                     (void) = 0;
+	virtual void SendHeldItemChange             (int a_ItemIndex) = 0;
 	virtual void SendHideTitle                  (void) = 0;
 	virtual void SendInventorySlot              (char a_WindowID, short a_SlotNum, const cItem & a_Item) = 0;
 	virtual void SendKeepAlive                  (UInt32 a_PingID) = 0;

src/Protocol/ProtocolRecognizer.cpp

@@ -428,6 +428,17 @@ void cProtocolRecognizer::SendHealth(void)
 
 
 
+void cProtocolRecognizer::SendHeldItemChange(int a_ItemIndex)
+{
+	ASSERT(m_Protocol != nullptr);
+	m_Protocol->SendHeldItemChange(a_ItemIndex);
+}
+
+
+
+
+
+
 void cProtocolRecognizer::SendHideTitle(void)
 {
 	ASSERT(m_Protocol != nullptr);

src/Protocol/ProtocolRecognizer.h

@@ -85,6 +85,7 @@ public:
 	virtual void SendExplosion                  (double a_BlockX, double a_BlockY, double a_BlockZ, float a_Radius, const cVector3iArray & a_BlocksAffected, const Vector3d & a_PlayerMotion) override;
 	virtual void SendGameMode                   (eGameMode a_GameMode) override;
 	virtual void SendHealth                     (void) override;
+	virtual void SendHeldItemChange             (int a_ItemIndex) override;
 	virtual void SendHideTitle                  (void) override;
 	virtual void SendInventorySlot              (char a_WindowID, short a_SlotNum, const cItem & a_Item) override;
 	virtual void SendKeepAlive                  (UInt32 a_PingID) override;

src/Protocol/Protocol_1_8.cpp

@@ -592,6 +592,19 @@ void cProtocol_1_8_0::SendHealth(void)
 
 
 
+void cProtocol_1_8_0::SendHeldItemChange(int a_ItemIndex)
+{
+	ASSERT((a_ItemIndex >= 0) && (a_ItemIndex <= 8));  // Valid check
+
+	cPacketizer Pkt(*this, 0x09);  // Held item change
+	cPlayer * Player = m_Client->GetPlayer();
+	Pkt.WriteBEInt8(static_cast<Int8>(Player->GetInventory().GetEquippedSlotNum()));
+}
+
+
+
+
+
 void cProtocol_1_8_0::SendHideTitle(void)
 {
 	ASSERT(m_State == 3);  // In game mode?

src/Protocol/Protocol_1_8.h

@@ -77,6 +77,7 @@ public:
 	virtual void SendExplosion                  (double a_BlockX, double a_BlockY, double a_BlockZ, float a_Radius, const cVector3iArray & a_BlocksAffected, const Vector3d & a_PlayerMotion) override;
 	virtual void SendGameMode                   (eGameMode a_GameMode) override;
 	virtual void SendHealth                     (void) override;
+	virtual void SendHeldItemChange             (int a_ItemIndex) override;
 	virtual void SendHideTitle                  (void) override;
 	virtual void SendInventorySlot              (char a_WindowID, short a_SlotNum, const cItem & a_Item) override;
 	virtual void SendKeepAlive                  (UInt32 a_PingID) override;

src/Protocol/Protocol_1_9.cpp

@@ -636,6 +636,20 @@ void cProtocol_1_9_0::SendHealth(void)
 
 
 
+void cProtocol_1_9_0::SendHeldItemChange(int a_ItemIndex)
+{
+	ASSERT((a_ItemIndex >= 0) && (a_ItemIndex <= 8));  // Valid check
+
+	cPacketizer Pkt(*this, GetPacketId(sendHeldItemChange));  // Held item change
+	cPlayer * Player = m_Client->GetPlayer();
+	Pkt.WriteBEInt8(static_cast<Int8>(Player->GetInventory().GetEquippedSlotNum()));
+}
+
+
+
+
+
+
 void cProtocol_1_9_0::SendHideTitle(void)
 {
 	ASSERT(m_State == 3);  // In game mode?

src/Protocol/Protocol_1_9.h

@@ -83,6 +83,7 @@ public:
 	virtual void SendExplosion                  (double a_BlockX, double a_BlockY, double a_BlockZ, float a_Radius, const cVector3iArray & a_BlocksAffected, const Vector3d & a_PlayerMotion) override;
 	virtual void SendGameMode                   (eGameMode a_GameMode) override;
 	virtual void SendHealth                     (void) override;
+	virtual void SendHeldItemChange             (int a_ItemIndex) override;
 	virtual void SendHideTitle                  (void) override;
 	virtual void SendInventorySlot              (char a_WindowID, short a_SlotNum, const cItem & a_Item) override;
 	virtual void SendKeepAlive                  (UInt32 a_PingID) override;