Basic elytra flight (#5124)

* Basic elytra flight

Co-authored-by: 12xx12 <44411062+12xx12@users.noreply.github.com>
Co-authored-by: Tiger Wang <ziwei.tiger@outlook.com>

Server/Plugins/APIDump/APIDesc.lua

@@ -4071,6 +4071,16 @@ local Hash = cCryptoHash.sha1HexString("DataToHash")
 					},
 					Notes = "Returns true if the entity is sprinting. Entities that cannot sprint return always false",
 				},
+				IsElytraFlying =
+				{
+					Returns =
+					{
+						{
+							Type = "boolean",
+						},
+					},
+					Notes = "Returns true if the entity is flying with an elytra. Entities that cannot fly with an elytra return always false",
+				},
 				IsSubmerged =
 				{
 					Returns =
@@ -10537,16 +10547,6 @@ a_Player:OpenWindow(Window);
 					},
 					Notes = "Returns the player's current set of skin part flags.  This is a bitwise OR of various {{Globals#eSkinPart|eSkinPart}} constants.  Note that HasSkinPart may be easier to use in most situations.",
 				},
-				GetStance =
-				{
-					Returns =
-					{
-						{
-							Type = "number",
-						},
-					},
-					Notes = "Returns the player's stance (Y-pos of player's eyes)",
-				},
 				GetTeam =
 				{
 					Returns =
@@ -11277,6 +11277,17 @@ a_Player:OpenWindow(Window);
 					},
 					Notes = "Sets the skin part flags of the player.  The value should be a bitwise OR of several {{Globals#eSkinPart|eSkinPart}} constants.",
 				},
+				SetElytraFlight =
+				{
+					Params =
+					{
+						{
+							Name = "IsElytraFlying",
+							Type = "boolean",
+						},
+					},
+					Notes = "Sets whether the player is elytra flying or not.",
+				},
 				SetSprintingMaxSpeed =
 				{
 					Params =

src/ClientHandle.cpp

@@ -574,12 +574,9 @@ void cClientHandle::HandleNPCTrade(int a_SlotNum)
 
 
 
-void cClientHandle::HandleOpenHorseInventory(UInt32 a_EntityID)
+void cClientHandle::HandleOpenHorseInventory()
 {
-	if (m_Player->GetUniqueID() == a_EntityID)
+	m_Player->OpenHorseInventory();
-	{
-		m_Player->OpenHorseInventory();
-	}
 }
 
 
@@ -665,6 +662,15 @@ void cClientHandle::HandleCreativeInventory(Int16 a_SlotNum, const cItem & a_Hel
 
 
 
+void cClientHandle::HandleCrouch(const bool a_IsCrouching)
+{
+	m_Player->SetCrouch(a_IsCrouching);
+}
+
+
+
+
+
 void cClientHandle::HandleEnchantItem(UInt8 a_WindowID, UInt8 a_Enchantment)
 {
 	if (a_Enchantment > 2)
@@ -749,7 +755,7 @@ void cClientHandle::HandlePlayerAbilities(bool a_IsFlying, float FlyingSpeed, fl
 
 
 
-void cClientHandle::HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ, double a_Stance, bool a_IsOnGround)
+void cClientHandle::HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ, bool a_IsOnGround)
 {
 	if (m_Player->IsFrozen())
 	{
@@ -759,7 +765,6 @@ void cClientHandle::HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ,
 
 	Vector3d NewPosition(a_PosX, a_PosY, a_PosZ);
 	Vector3d OldPosition = GetPlayer()->GetPosition();
-	double OldStance = GetPlayer()->GetStance();
 	auto PreviousIsOnGround = GetPlayer()->IsOnGround();
 
 	#ifdef __clang__
@@ -769,7 +774,6 @@ void cClientHandle::HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ,
 
 	if (
 		(OldPosition == NewPosition) &&
-		(OldStance == a_Stance) &&
 		(PreviousIsOnGround == a_IsOnGround)
 	)
 	{
@@ -799,7 +803,6 @@ void cClientHandle::HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ,
 	// TODO: Official server refuses position packets too far away from each other, kicking "hacked" clients; we should, too
 
 	m_Player->SetPosition(NewPosition);
-	m_Player->SetStance(a_Stance);
 	m_Player->SetTouchGround(a_IsOnGround);
 	m_Player->UpdateMovementStats(NewPosition - OldPosition, PreviousIsOnGround);
 }
@@ -1513,9 +1516,9 @@ void cClientHandle::HandlePlayerLook(float a_Rotation, float a_Pitch, bool a_IsO
 
 
 
-void cClientHandle::HandlePlayerMoveLook(double a_PosX, double a_PosY, double a_PosZ, double a_Stance, float a_Rotation, float a_Pitch, bool a_IsOnGround)
+void cClientHandle::HandlePlayerMoveLook(double a_PosX, double a_PosY, double a_PosZ, float a_Rotation, float a_Pitch, bool a_IsOnGround)
 {
-	HandlePlayerPos(a_PosX, a_PosY, a_PosZ, a_Stance, a_IsOnGround);
+	HandlePlayerPos(a_PosX, a_PosY, a_PosZ, a_IsOnGround);
 	HandlePlayerLook(a_Rotation, a_Pitch, a_IsOnGround);
 }
 
@@ -1567,6 +1570,24 @@ void cClientHandle::HandleSpectate(const cUUID & a_PlayerUUID)
 
 
 
+void cClientHandle::HandleSprint(const bool a_IsSprinting)
+{
+	m_Player->SetSprint(a_IsSprinting);
+}
+
+
+
+
+
+void cClientHandle::HandleStartElytraFlight()
+{
+	m_Player->SetElytraFlight(true);
+}
+
+
+
+
+
 void cClientHandle::HandleSteerVehicle(float a_Forward, float a_Sideways)
 {
 	m_Player->SteerVehicle(a_Forward, a_Sideways);
@@ -1831,47 +1852,11 @@ bool cClientHandle::HandleHandshake(const AString & a_Username)
 
 
 
-void cClientHandle::HandleEntityCrouch(UInt32 a_EntityID, bool a_IsCrouching)
+void cClientHandle::HandleLeaveBed()
 {
-	if (a_EntityID != m_Player->GetUniqueID())
+	cChunkInterface Interface(m_Player->GetWorld()->GetChunkMap());
-	{
+	cBlockBedHandler::SetBedOccupationState(Interface, m_Player->GetLastBedPos(), false);
-		// We should only receive entity actions from the entity that is performing the action
+	m_Player->SetIsInBed(false);
-		return;
-	}
-
-	m_Player->SetCrouch(a_IsCrouching);
-}
-
-
-
-
-
-void cClientHandle::HandleEntityLeaveBed(UInt32 a_EntityID)
-{
-	if (a_EntityID != m_Player->GetUniqueID())
-	{
-		// We should only receive entity actions from the entity that is performing the action
-		return;
-	}
-
-	cChunkInterface Interface(GetPlayer()->GetWorld()->GetChunkMap());
-	cBlockBedHandler::SetBedOccupationState(Interface, GetPlayer()->GetLastBedPos(), false);
-	GetPlayer()->SetIsInBed(false);
-}
-
-
-
-
-
-void cClientHandle::HandleEntitySprinting(UInt32 a_EntityID, bool a_IsSprinting)
-{
-	if (a_EntityID != m_Player->GetUniqueID())
-	{
-		// We should only receive entity actions from the entity that is performing the action
-		return;
-	}
-
-	m_Player->SetSprint(a_IsSprinting);
 }
 
 

src/ClientHandle.h

@@ -322,13 +322,12 @@ public:  // tolua_export
 	a_ClickAction specifies whether the click was inside the window or not (caLeftClick or caLeftClickOutside). */
 	void HandleCreativeInventory(Int16 a_SlotNum, const cItem & a_HeldItem, eClickAction a_ClickAction);
 
+	/** Handles a player sneaking or unsneaking. */
+	void HandleCrouch(bool a_IsCrouching);
+
 	/** Called when the player enchants an Item in the Enchanting table UI. */
 	void HandleEnchantItem(UInt8 a_WindowID, UInt8 a_Enchantment);
 
-	void HandleEntityCrouch           (UInt32 a_EntityID, bool a_IsCrouching);
-	void HandleEntityLeaveBed         (UInt32 a_EntityID);
-	void HandleEntitySprinting        (UInt32 a_EntityID, bool a_IsSprinting);
-
 	/** Kicks the client if the same username is already logged in.
 	Returns false if the client has been kicked, true otherwise. */
 	bool CheckMultiLogin(const AString & a_Username);
@@ -339,6 +338,9 @@ public:  // tolua_export
 	*/
 	bool HandleHandshake        (const AString & a_Username);
 
+	/** Handles a player exiting his bed. */
+	void HandleLeaveBed();
+
 	void HandleKeepAlive        (UInt32 a_KeepAliveID);
 	void HandleLeftClick        (int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace, UInt8 a_Status);
 
@@ -346,20 +348,19 @@ public:  // tolua_export
 	the NPC UI. */
 	void HandleNPCTrade(int a_SlotNum);
 
-	/** Handles a player opening their inventory while riding a horse.
+	/** Handles a player opening his inventory while riding a horse. */
-	@param a_EntityID ID of the player that is to open the inventory. Should be the same as GetPlayer()->GetUniqueID().  */
+	void HandleOpenHorseInventory();
-	void HandleOpenHorseInventory(UInt32 a_EntityID);
 
 	void HandlePing             (void);
 	void HandlePlayerAbilities  (bool a_IsFlying, float FlyingSpeed, float WalkingSpeed);
 	void HandlePlayerLook       (float a_Rotation, float a_Pitch, bool a_IsOnGround);
-	void HandlePlayerMoveLook   (double a_PosX, double a_PosY, double a_PosZ, double a_Stance, float a_Rotation, float a_Pitch, bool a_IsOnGround);  // While m_bPositionConfirmed (normal gameplay)
+	void HandlePlayerMoveLook   (double a_PosX, double a_PosY, double a_PosZ, float a_Rotation, float a_Pitch, bool a_IsOnGround);  // While m_bPositionConfirmed (normal gameplay)
 
 	/** Verifies and sets player position, performing relevant checks
 	Calls relevant methods to process movement related statistics
 	Requires state of previous position and on-ground status, so must be called when these are still intact
 	*/
-	void HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ, double a_Stance, bool a_IsOnGround);
+	void HandlePlayerPos(double a_PosX, double a_PosY, double a_PosZ, bool a_IsOnGround);
 
 
 	void HandlePluginMessage    (const AString & a_Channel, ContiguousByteBufferView a_Message);
@@ -367,6 +368,13 @@ public:  // tolua_export
 	void HandleRightClick       (int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace, int a_CursorX, int a_CursorY, int a_CursorZ, eHand a_Hand);
 	void HandleSlotSelected     (Int16 a_SlotNum);
 	void HandleSpectate         (const cUUID & a_PlayerUUID);
+
+	/** Handles a player sprinting or slowing back down. */
+	void HandleSprint(bool a_IsSprinting);
+
+	/** Handles a player starting elytra flight while falling. */
+	void HandleStartElytraFlight();
+
 	void HandleSteerVehicle     (float Forward, float Sideways);
 	void HandleTabCompletion    (const AString & a_Text);
 	void HandleUpdateSign       (

src/Defines.cpp

@@ -535,6 +535,7 @@ bool ItemCategory::IsHelmet(short a_ItemType)
 bool ItemCategory::IsChestPlate(short a_ItemType)
 {
 	return (
+		(a_ItemType == E_ITEM_ELYTRA) ||
 		(a_ItemType == E_ITEM_LEATHER_TUNIC) ||
 		(a_ItemType == E_ITEM_GOLD_CHESTPLATE) ||
 		(a_ItemType == E_ITEM_CHAIN_CHESTPLATE) ||

src/Entities/Entity.cpp

@@ -59,6 +59,8 @@ cEntity::cEntity(eEntityType a_EntityType, Vector3d a_Pos, double a_Width, doubl
 	m_IsInLava(false),
 	m_IsInWater(false),
 	m_IsHeadInWater(false),
+	m_Width(a_Width),
+	m_Height(a_Height),
 	m_AirLevel(MAX_AIR_LEVEL),
 	m_AirTickTimer(DROWNING_TICKS),
 	m_TicksAlive(0),
@@ -69,8 +71,6 @@ cEntity::cEntity(eEntityType a_EntityType, Vector3d a_Pos, double a_Width, doubl
 	m_Position(a_Pos),
 	m_WaterSpeed(0, 0, 0),
 	m_Mass (0.001),  // Default 1g
-	m_Width(a_Width),
-	m_Height(a_Height),
 	m_InvulnerableTicks(0)
 {
 	m_WorldChangeInfo.m_NewWorld = nullptr;
@@ -2028,15 +2028,6 @@ void cEntity::SetHeadYaw(double a_HeadYaw)
 
 
 
-void cEntity::SetHeight(double a_Height)
-{
-	m_Height = a_Height;
-}
-
-
-
-
-
 void cEntity::SetMass(double a_Mass)
 {
 	// Make sure that mass is not zero. 1g is the default because we
@@ -2118,15 +2109,6 @@ void cEntity::SetSpeedZ(double a_SpeedZ)
 
 
 
-void cEntity::SetWidth(double a_Width)
-{
-	m_Width = a_Width;
-}
-
-
-
-
-
 void cEntity::AddSpeed(double a_AddSpeedX, double a_AddSpeedY, double a_AddSpeedZ)
 {
 	SetSpeed(m_Speed.x + a_AddSpeedX, m_Speed.y + a_AddSpeedY, m_Speed.z + a_AddSpeedZ);

src/Entities/Entity.h

@@ -328,10 +328,6 @@ public:
 
 	// tolua_end
 
-	void SetHeight(double a_Height);
-
-	void SetWidth(double a_Width);
-
 	/** Exported in ManualBindings */
 	const Vector3d & GetPosition(void) const { return m_Position; }
 
@@ -522,12 +518,13 @@ public:
 	// tolua_begin
 
 	// COMMON metadata flags; descendants may override the defaults:
-	virtual bool IsOnFire   (void) const {return (m_TicksLeftBurning > 0); }
+	virtual bool IsCrouched    (void) const { return false; }
-	virtual bool IsCrouched (void) const {return false; }
+	virtual bool IsElytraFlying(void) const { return false; }
-	virtual bool IsRiding   (void) const {return false; }
+	virtual bool IsInvisible   (void) const { return false; }
-	virtual bool IsSprinting(void) const {return false; }
+	virtual bool IsOnFire      (void) const { return m_TicksLeftBurning > 0; }
-	virtual bool IsRclking  (void) const {return false; }
+	virtual bool IsRclking     (void) const { return false; }
-	virtual bool IsInvisible(void) const { return false; }
+	virtual bool IsRiding      (void) const { return false; }
+	virtual bool IsSprinting   (void) const { return false; }
 
 	/** Returns true if any part of the entity is in a fire block */
 	virtual bool IsInFire(void) const { return m_IsInFire; }
@@ -689,6 +686,12 @@ protected:
 	/** If the entity's head is in a water block */
 	bool m_IsHeadInWater;
 
+	/** Width of the entity, in the XZ plane. Since entities are represented as cylinders, this is more of a diameter. */
+	double m_Width;
+
+	/** Height of the entity (Y axis). */
+	double m_Height;
+
 	/** Air level of a mobile */
 	int m_AirLevel;
 	int m_AirTickTimer;
@@ -745,12 +748,6 @@ private:
 	/** Measured in Kilograms (Kg) */
 	double m_Mass;
 
-	/** Width of the entity, in the XZ plane. Since entities are represented as cylinders, this is more of a diameter. */
-	double m_Width;
-
-	/** Height of the entity (Y axis) */
-	double m_Height;
-
 	/** If a player hit a entity, the entity receive a invulnerable of 10 ticks.
 	While this ticks, a player can't hit this entity. */
 	int m_InvulnerableTicks;

src/Entities/Minecart.cpp

@@ -106,8 +106,6 @@ cMinecart::cMinecart(ePayload a_Payload, Vector3d a_Pos):
 	SetAirDrag(0.05f);
 	SetMaxHealth(6);
 	SetHealth(6);
-	SetWidth(1);
-	SetHeight(0.9);
 }
 
 
@@ -1274,10 +1272,10 @@ void cMinecart::ApplyAcceleration(Vector3d a_ForwardDirection, double a_Accelera
 ////////////////////////////////////////////////////////////////////////////////
 // cRideableMinecart:
 
-cRideableMinecart::cRideableMinecart(Vector3d a_Pos, const cItem & a_Content, int a_Height):
+cRideableMinecart::cRideableMinecart(Vector3d a_Pos, const cItem & a_Content, int a_ContentHeight):
 	Super(mpNone, a_Pos),
 	m_Content(a_Content),
-	m_Height(a_Height)
+	m_ContentHeight(a_ContentHeight)
 {
 }
 

src/Entities/Minecart.h

@@ -105,10 +105,10 @@ public:
 
 	CLASS_PROTODEF(cRideableMinecart)
 
-	cRideableMinecart(Vector3d a_Pos, const cItem & a_Content, int a_Height);
+	cRideableMinecart(Vector3d a_Pos, const cItem & a_Content, int a_ContentHeight);
 
-	const cItem & GetContent(void) const {return m_Content;}
+	const cItem & GetContent(void) const { return m_Content; }
-	int GetBlockHeight(void) const {return m_Height;}
+	int GetBlockHeight(void) const { return m_ContentHeight; }
 
 	// cEntity overrides:
 	virtual void GetDrops(cItems & a_Drops, cEntity * a_Killer = nullptr) override;
@@ -116,9 +116,8 @@ public:
 
 protected:
 
-
 	cItem m_Content;
-	int m_Height;
+	int m_ContentHeight;
 } ;
 
 

src/Entities/Pawn.cpp

@@ -418,6 +418,11 @@ void cPawn::HandleFalling(void)
 		auto Damage = static_cast<int>(m_LastGroundHeight - GetPosY() - 3.0);
 		if ((Damage > 0) && !FallDamageAbsorbed)
 		{
+			if (IsElytraFlying())
+			{
+				Damage = static_cast<int>(static_cast<float>(Damage) * 0.33);
+			}
+
 			TakeDamage(dtFalling, nullptr, Damage, static_cast<float>(Damage), 0);
 
 			// Fall particles

src/Entities/Player.cpp

@@ -66,38 +66,72 @@ const int cPlayer::EATING_TICKS = 30;
 
 
 
+cPlayer::BodyStanceCrouching::BodyStanceCrouching(cPlayer & a_Player)
+{
+	a_Player.SetSize(0.6f, 1.65f);
+}
+
+
+
+
+
+cPlayer::BodyStanceSleeping::BodyStanceSleeping(cPlayer & a_Player)
+{
+	a_Player.SetSize(0.2f, 0.2f);
+}
+
+
+
+
+
+cPlayer::BodyStanceStanding::BodyStanceStanding(cPlayer & a_Player)
+{
+	a_Player.SetSize(0.6f, 1.8f);
+}
+
+
+
+
+
+cPlayer::BodyStanceGliding::BodyStanceGliding(cPlayer & a_Player) :
+	TicksElytraFlying(0)
+{
+	a_Player.SetSize(0.6f, 0.6f);
+}
+
+
+
+
+
 cPlayer::cPlayer(const std::shared_ptr<cClientHandle> & a_Client) :
 	Super(etPlayer, 0.6, 1.8),
-	m_bVisible(true),
+	m_BodyStance(BodyStanceStanding(*this)),
 	m_FoodLevel(MAX_FOOD_LEVEL),
 	m_FoodSaturationLevel(5.0),
 	m_FoodTickTimer(0),
 	m_FoodExhaustionLevel(0.0),
-	m_Stance(0.0),
 	m_Inventory(*this),
 	m_EnderChestContents(9, 3),
 	m_DefaultWorldPath(cRoot::Get()->GetDefaultWorld()->GetDataPath()),
 	m_GameMode(eGameMode_NotSet),
 	m_ClientHandle(a_Client),
-	m_IsFrozen(false),
 	m_NormalMaxSpeed(1.0),
 	m_SprintingMaxSpeed(1.3),
 	m_FlyingMaxSpeed(1.0),
-	m_IsCrouched(false),
+	m_IsChargingBow(false),
-	m_IsSprinting(false),
-	m_IsFlying(false),
 	m_IsFishing(false),
-	m_CanFly(false),
+	m_IsFlightCapable(false),
+	m_IsFlying(false),
+	m_IsFrozen(false),
+	m_IsTeleporting(false),
+	m_IsVisible(true),
 	m_EatingFinishTick(-1),
 	m_LifetimeTotalXp(0),
 	m_CurrentXp(0),
-	m_IsChargingBow(false),
 	m_BowCharge(0),
 	m_FloaterID(cEntity::INVALID_ID),
 	m_Team(nullptr),
-	m_bIsInBed(false),
 	m_TicksUntilNextSave(PLAYER_INVENTORY_SAVE_INTERVAL),
-	m_bIsTeleporting(false),
 	m_SkinParts(0),
 	m_MainHand(mhRight)
 {
@@ -114,26 +148,25 @@ cPlayer::cPlayer(const std::shared_ptr<cClientHandle> & a_Client) :
 	LoadFromDisk(World);
 
 	m_LastGroundHeight = static_cast<float>(GetPosY());
-	m_Stance = GetPosY() + 1.62;
 
 	if (m_GameMode == gmNotSet)
 	{
 		if (World->IsGameModeCreative())
 		{
-			m_CanFly = true;
+			m_IsFlightCapable = true;
 		}
 		if (World->IsGameModeSpectator())  // Otherwise Player will fall out of the world on join
 		{
-			m_CanFly = true;
+			m_IsFlightCapable = true;
 			m_IsFlying = true;
 		}
 	}
 
 	if (m_GameMode == gmSpectator)  // If player is reconnecting to the server in spectator mode
 	{
-		m_CanFly = true;
+		m_IsFlightCapable = true;
 		m_IsFlying = true;
-		m_bVisible = false;
+		m_IsVisible = false;
 	}
 }
 
@@ -427,6 +460,24 @@ void cPlayer::AddFoodExhaustion(double a_Exhaustion)
 
 
 
+bool cPlayer::IsInBed(void) const
+{
+	return std::holds_alternative<BodyStanceSleeping>(m_BodyStance);
+}
+
+
+
+
+
+bool cPlayer::IsStanding() const
+{
+	return std::holds_alternative<BodyStanceStanding>(m_BodyStance);
+}
+
+
+
+
+
 void cPlayer::TossItems(const cItems & a_Items)
 {
 	if (IsGameModeSpectator())  // Players can't toss items in spectator
@@ -445,6 +496,23 @@ void cPlayer::TossItems(const cItems & a_Items)
 
 
 
+void cPlayer::SetIsInBed(const bool a_GoToBed)
+{
+	if (a_GoToBed && IsStanding())
+	{
+		m_BodyStance = BodyStanceSleeping(*this);
+	}
+	else if (!a_GoToBed && IsInBed())
+	{
+		m_BodyStance = BodyStanceStanding(*this);
+		GetWorld()->BroadcastEntityAnimation(*this, 2);
+	}
+}
+
+
+
+
+
 void cPlayer::StartEating(void)
 {
 	// Set the timer:
@@ -525,11 +593,11 @@ const cSlotNums & cPlayer::GetInventoryPaintSlots(void) const
 
 double cPlayer::GetMaxSpeed(void) const
 {
-	if (m_IsFlying)
+	if (IsFlying())
 	{
 		return m_FlyingMaxSpeed;
 	}
-	else if (m_IsSprinting)
+	else if (IsSprinting())
 	{
 		return m_SprintingMaxSpeed;
 	}
@@ -546,7 +614,7 @@ double cPlayer::GetMaxSpeed(void) const
 void cPlayer::SetNormalMaxSpeed(double a_Speed)
 {
 	m_NormalMaxSpeed = a_Speed;
-	if (!m_IsSprinting && !m_IsFlying && !m_IsFrozen)
+	if (!IsSprinting() && !IsFlying() && !IsFrozen())
 	{
 		// If we are frozen, we do not send this yet. We send when unfreeze() is called
 		m_ClientHandle->SendPlayerMaxSpeed();
@@ -560,7 +628,7 @@ void cPlayer::SetNormalMaxSpeed(double a_Speed)
 void cPlayer::SetSprintingMaxSpeed(double a_Speed)
 {
 	m_SprintingMaxSpeed = a_Speed;
-	if (m_IsSprinting && !m_IsFlying && !m_IsFrozen)
+	if (IsSprinting() && !m_IsFlying && !m_IsFrozen)
 	{
 		// If we are frozen, we do not send this yet. We send when unfreeze() is called
 		m_ClientHandle->SendPlayerMaxSpeed();
@@ -587,21 +655,18 @@ void cPlayer::SetFlyingMaxSpeed(double a_Speed)
 
 
 
-void cPlayer::SetCrouch(bool a_IsCrouched)
+void cPlayer::SetCrouch(const bool a_ShouldCrouch)
 {
-	// Set the crouch status, broadcast to all visible players
+	if (a_ShouldCrouch && IsStanding())
-	if (a_IsCrouched == m_IsCrouched)
-	{
-		// No change
-		return;
-	}
-
-	if (a_IsCrouched)
 	{
+		m_BodyStance = BodyStanceCrouching(*this);
 		cRoot::Get()->GetPluginManager()->CallHookPlayerCrouched(*this);
 	}
+	else if (!a_ShouldCrouch && IsCrouched())
+	{
+		m_BodyStance = BodyStanceStanding(*this);
+	}
 
-	m_IsCrouched = a_IsCrouched;
 	m_World->BroadcastEntityMetadata(*this);
 }
 
@@ -609,16 +674,55 @@ void cPlayer::SetCrouch(bool a_IsCrouched)
 
 
 
-void cPlayer::SetSprint(bool a_IsSprinting)
+void cPlayer::SetElytraFlight(const bool a_ShouldElytraFly)
 {
-	if (a_IsSprinting == m_IsSprinting)
+	if (a_ShouldElytraFly && IsStanding() && !IsOnGround() && !IsInWater() && !IsRiding() && (GetEquippedChestplate().m_ItemType == E_ITEM_ELYTRA))
+	{
+		m_BodyStance = BodyStanceGliding(*this);
+	}
+	else if (!a_ShouldElytraFly && IsElytraFlying())
+	{
+		m_BodyStance = BodyStanceStanding(*this);
+	}
+
+	m_World->BroadcastEntityMetadata(*this);
+}
+
+
+
+
+
+void cPlayer::SetFlying(const bool a_ShouldFly)
+{
+	if (a_ShouldFly == m_IsFlying)
 	{
-		// No change
 		return;
 	}
 
-	m_IsSprinting = a_IsSprinting;
+	m_IsFlying = a_ShouldFly;
-	m_ClientHandle->SendPlayerMaxSpeed();
+	if (!m_IsFrozen)
+	{
+		// If we are frozen, we do not send this yet. We send when unfreeze() is called
+		m_ClientHandle->SendPlayerAbilities();
+	}
+}
+
+
+
+
+
+void cPlayer::SetSprint(const bool a_ShouldSprint)
+{
+	if (a_ShouldSprint && IsStanding())
+	{
+		m_BodyStance = BodyStanceSprinting();
+	}
+	else if (!a_ShouldSprint && IsSprinting())
+	{
+		m_BodyStance = BodyStanceStanding(*this);
+	}
+
+	m_World->BroadcastEntityMetadata(*this);
 }
 
 
@@ -627,12 +731,12 @@ void cPlayer::SetSprint(bool a_IsSprinting)
 
 void cPlayer::SetCanFly(bool a_CanFly)
 {
-	if (a_CanFly == m_CanFly)
+	if (a_CanFly == m_IsFlightCapable)
 	{
 		return;
 	}
 
-	m_CanFly = a_CanFly;
+	m_IsFlightCapable = a_CanFly;
 	m_ClientHandle->SendPlayerAbilities();
 }
 
@@ -698,25 +802,6 @@ cWorld * cPlayer::GetBedWorld()
 
 
 
-void cPlayer::SetFlying(bool a_IsFlying)
-{
-	if (a_IsFlying == m_IsFlying)
-	{
-		return;
-	}
-
-	m_IsFlying = a_IsFlying;
-	if (!m_IsFrozen)
-	{
-		// If we are frozen, we do not send this yet. We send when unfreeze() is called
-		m_ClientHandle->SendPlayerAbilities();
-	}
-}
-
-
-
-
-
 void cPlayer::NotifyNearbyWolves(cPawn * a_Opponent, bool a_IsPlayerInvolved)
 {
 	ASSERT(a_Opponent != nullptr);
@@ -750,7 +835,7 @@ void cPlayer::KilledBy(TakeDamageInfo & a_TDI)
 		return;  //  not dead yet =]
 	}
 
-	m_bVisible = false;  // So new clients don't see the player
+	m_IsVisible = false;  // So new clients don't see the player
 
 	// Detach player from object / entity. If the player dies, the server still says
 	// that the player is attached to the entity / object
@@ -905,7 +990,7 @@ void cPlayer::Respawn(void)
 
 double cPlayer::GetEyeHeight(void) const
 {
-	return m_Stance;
+	return GetEyePosition().y - GetPosY();
 }
 
 
@@ -914,7 +999,22 @@ double cPlayer::GetEyeHeight(void) const
 
 Vector3d cPlayer::GetEyePosition(void) const
 {
-	return Vector3d( GetPosX(), m_Stance, GetPosZ());
+	if (IsCrouched())
+	{
+		return GetPosition().addedY(1.54);
+	}
+
+	if (IsElytraFlying())
+	{
+		return GetPosition().addedY(0.4);
+	}
+
+	if (IsInBed())
+	{
+		return GetPosition().addedY(0.2);
+	}
+
+	return GetPosition().addedY(1.6);
 }
 
 
@@ -1314,7 +1414,7 @@ void cPlayer::TeleportToCoords(double a_PosX, double a_PosY, double a_PosZ)
 	{
 		SetPosition({a_PosX, a_PosY, a_PosZ});
 		FreezeInternal(GetPosition(), false);
-		m_bIsTeleporting = true;
+		m_IsTeleporting = true;
 
 		m_ClientHandle->SendPlayerMoveLook();
 	}
@@ -1344,6 +1444,11 @@ bool cPlayer::IsFrozen()
 
 void cPlayer::Unfreeze()
 {
+	if (IsElytraFlying())
+	{
+		m_World->BroadcastEntityMetadata(*this);
+	}
+
 	GetClientHandle()->SendPlayerAbilities();
 	GetClientHandle()->SendPlayerMaxSpeed();
 
@@ -1449,14 +1554,14 @@ void cPlayer::ForceSetSpeed(const Vector3d & a_Speed)
 void cPlayer::SetVisible(bool a_bVisible)
 {
 	// Need to Check if the player or other players are in gamemode spectator, but will break compatibility
-	if (a_bVisible && !m_bVisible)  // Make visible
+	if (a_bVisible && !m_IsVisible)  // Make visible
 	{
-		m_bVisible = true;
+		m_IsVisible = true;
 		m_World->BroadcastSpawnEntity(*this);
 	}
-	if (!a_bVisible && m_bVisible)
+	if (!a_bVisible && m_IsVisible)
 	{
-		m_bVisible = false;
+		m_IsVisible = false;
 		m_World->BroadcastDestroyEntity(*this, m_ClientHandle.get());  // Destroy on all clients
 	}
 }
@@ -1809,7 +1914,7 @@ bool cPlayer::LoadFromFile(const AString & a_FileName, cWorldPtr & a_World)
 
 	if (m_GameMode == eGameMode_Creative)
 	{
-		m_CanFly = true;
+		m_IsFlightCapable = true;
 	}
 
 	m_Inventory.LoadFromJson(Root["inventory"]);
@@ -2141,9 +2246,9 @@ bool cPlayer::IsClimbing(void) const
 
 void cPlayer::UpdateMovementStats(const Vector3d & a_DeltaPos, bool a_PreviousIsOnGround)
 {
-	if (m_bIsTeleporting)
+	if (m_IsTeleporting)
 	{
-		m_bIsTeleporting = false;
+		m_IsTeleporting = false;
 		return;
 	}
 
@@ -2599,16 +2704,19 @@ float cPlayer::GetLiquidHeightPercent(NIBBLETYPE a_Meta)
 
 bool cPlayer::IsInsideWater()
 {
-	BLOCKTYPE Block = m_World->GetBlock(Vector3d(GetPosX(), m_Stance, GetPosZ()).Floor());
+	BLOCKTYPE Block;
+	NIBBLETYPE Meta;
+	m_World->GetBlockTypeMeta(GetEyePosition().Floor(), Block, Meta);
+
 	if ((Block != E_BLOCK_WATER) && (Block != E_BLOCK_STATIONARY_WATER))
 	{
 		return false;
 	}
-	NIBBLETYPE Meta = GetWorld()->GetBlockMeta(Vector3d(GetPosX(), m_Stance, GetPosZ()).Floor());
+
+	const auto EyeHeight = GetEyeHeight();
 	float f = GetLiquidHeightPercent(Meta) - 0.11111111f;
-	float f1 = static_cast<float>(m_Stance + 1) - f;
+	float f1 = static_cast<float>(EyeHeight + 1) - f;
-	bool flag = (m_Stance < f1);
+	return EyeHeight < f1;
-	return flag;
 }
 
 
@@ -2742,6 +2850,16 @@ void cPlayer::AddKnownItem(const cItem & a_Item)
 
 
 
+void cPlayer::SetSize(const float a_Width, const float a_Height)
+{
+	m_Width = a_Width;
+	m_Height = a_Height;
+}
+
+
+
+
+
 void cPlayer::AddKnownRecipe(UInt32 a_RecipeId)
 {
 	auto Response = m_KnownRecipes.insert(a_RecipeId);
@@ -2916,6 +3034,33 @@ float cPlayer::GetEnchantmentBlastKnockbackReduction()
 
 
 
+bool cPlayer::IsCrouched(void) const
+{
+	return std::holds_alternative<BodyStanceCrouching>(m_BodyStance);
+}
+
+
+
+
+
+bool cPlayer::IsElytraFlying(void) const
+{
+	return std::holds_alternative<BodyStanceGliding>(m_BodyStance);
+}
+
+
+
+
+
+bool cPlayer::IsSprinting(void) const
+{
+	return std::holds_alternative<BodyStanceSprinting>(m_BodyStance);
+}
+
+
+
+
+
 void cPlayer::OnAddToWorld(cWorld & a_World)
 {
 	Super::OnAddToWorld(a_World);
@@ -3023,7 +3168,7 @@ void cPlayer::OnRemoveFromWorld(cWorld & a_World)
 
 void cPlayer::SpawnOn(cClientHandle & a_Client)
 {
-	if (!m_bVisible || (m_ClientHandle.get() == (&a_Client)))
+	if (!m_IsVisible || (m_ClientHandle.get() == (&a_Client)))
 	{
 		return;
 	}
@@ -3110,6 +3255,27 @@ void cPlayer::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 		m_BowCharge += 1;
 	}
 
+	if (IsElytraFlying())
+	{
+		// Damage elytra, once per second:
+		{
+			using namespace std::chrono_literals;
+
+			auto & TicksFlying = std::get<BodyStanceGliding>(m_BodyStance).TicksElytraFlying;
+			const auto TotalFlew = TicksFlying + a_Dt;
+			const auto Periods = static_cast<short>(TotalFlew / 1s);
+			TicksFlying = std::chrono::duration_cast<cTickTime>(TotalFlew - Periods * 1s);
+
+			UseItem(cInventory::invArmorOffset + 1, Periods);
+		}
+
+		// Check if flight is still possible:
+		if (IsOnGround() || IsInWater() || IsRiding() || (GetEquippedChestplate().m_ItemType != E_ITEM_ELYTRA))
+		{
+			SetElytraFlight(false);
+		}
+	}
+
 	BroadcastMovementUpdate(m_ClientHandle.get());
 
 	if (m_Health > 0)  // make sure player is alive

src/Entities/Player.h

@@ -27,11 +27,57 @@ class cTeam;
 class cPlayer:
 	public cPawn
 {
-
 	// tolua_end
 
 	using Super = cPawn;
 
+	/** Tag representing a sneaking pose. */
+	struct BodyStanceCrouching
+	{
+		BodyStanceCrouching(cPlayer & a_Player);
+	};
+
+	/** Tag representing a sleeping pose.
+	Set by a right click on unoccupied bed, unset by a time fast forward or teleport. */
+	struct BodyStanceSleeping
+	{
+		BodyStanceSleeping(cPlayer & a_Player);
+	};
+
+	/** Tag representing a sprinting pose. */
+	struct BodyStanceSprinting
+	{
+	};
+
+	/** Tag representing the neutral stance. */
+	struct BodyStanceStanding
+	{
+		BodyStanceStanding(cPlayer & a_Player);
+	};
+
+	/** Tag representing a swimming or elytra flying pose. */
+	struct BodyStanceGliding
+	{
+		BodyStanceGliding(cPlayer & a_Player);
+
+		cTickTime TicksElytraFlying;
+	};
+
+	/*
+	struct HandStanceNeutral
+	{
+	};
+
+	struct HandStandChargingBow
+	{
+		int m_BowCharge;
+	};
+
+	struct HandStanceEating
+	{
+	};
+	*/
+
 	// tolua_begin
 
 public:
@@ -105,11 +151,8 @@ public:
 	bool IsChargingBow(void) const { return m_IsChargingBow; }
 
 	void SetTouchGround(bool a_bTouchGround);
-	inline void SetStance(const double a_Stance) { m_Stance = a_Stance; }
 	double GetEyeHeight(void) const;  // tolua_export
 	Vector3d GetEyePosition(void) const;  // tolua_export
-	virtual bool IsOnGround(void) const override { return m_bTouchGround; }
-	inline double GetStance(void) const { return m_Stance; }  // tolua_export
 	inline cInventory &       GetInventory(void)       { return m_Inventory; }  // tolua_export
 	inline const cInventory & GetInventory(void) const { return m_Inventory; }
 
@@ -333,8 +376,8 @@ public:
 	/** Returns true if the player is currently flying */
 	bool IsFlying(void) const { return m_IsFlying; }
 
-	/** Returns true if a player is sleeping in a bed */
+	/** Returns true if a player is sleeping in a bed. */
-	bool IsInBed(void) const { return m_bIsInBed; }
+	bool IsInBed(void) const;
 
 	/** Returns true if the player has thrown out a floater */
 	bool IsFishing(void) const { return m_IsFishing; }
@@ -345,21 +388,16 @@ public:
 
 	// tolua_end
 
+	/** Returns true if a player is standing normally, that is, in a neutral pose. */
+	bool IsStanding() const;
+
 	/** Tosses a list of items. */
 	void TossItems(const cItems & a_Items);
 
-	/** Sets a player's in-bed state
+	/** Sets a player's in-bed state.
-	We can't be sure plugins will keep this value updated, so no exporting
+	We can't be sure plugins will keep this value updated, so no exporting.
-	If value is false (not in bed), will update players of the fact that they have been ejected from the bed
+	If value is false (not in bed), will update players of the fact that they have been ejected from the bed. */
-	*/
+	void SetIsInBed(bool a_IsInBed);
-	void SetIsInBed(bool a_Flag)
-	{
-		m_bIsInBed = a_Flag;
-		if (!a_Flag)
-		{
-			GetWorld()->BroadcastEntityAnimation(*this, 2);
-		}
-	}
 
 	/** Starts eating the currently equipped item. Resets the eating timer and sends the proper animation packet */
 	void StartEating(void);
@@ -377,7 +415,7 @@ public:
 	void Respawn(void);  // tolua_export
 
 	void SetVisible( bool a_bVisible);  // tolua_export
-	bool IsVisible(void) const { return m_bVisible; }  // tolua_export
+	bool IsVisible(void) const { return m_IsVisible; }  // tolua_export
 
 	/** Saves all player data, such as inventory, to JSON. */
 	void SaveToDisk(void);
@@ -450,14 +488,17 @@ public:
 	/** Sets the flying relative maximum speed. Sends the update to player, if needed. */
 	void SetFlyingMaxSpeed(double a_Speed);
 
-	/** Sets the crouch status, broadcasts to all visible players */
+	/** Starts or stops crouching, if our current body stance permits, broadcasting the state change. */
-	void SetCrouch(bool a_IsCrouched);
+	void SetCrouch(bool a_ShouldCrouch);
 
-	/** Starts or stops sprinting, sends the max speed update to the client, if needed */
+	/** Starts or stops elytra flight, if our current body stance permits, broadcasting the state change. */
-	void SetSprint(bool a_IsSprinting);
+	void SetElytraFlight(bool a_ShouldElytraFly);
 
-	/** Flags the player as flying */
+	/** Starts or stops flying, broadcasting the state change. */
-	void SetFlying(bool a_IsFlying);
+	void SetFlying(bool a_ShouldFly);
+
+	/** Starts or stops sprinting, if our current body stance permits, broadcasting the state change. */
+	void SetSprint(bool a_ShouldSprint);
 
 	/** If true the player can fly even when he's not in creative. */
 	void SetCanFly(bool a_CanFly);
@@ -501,7 +542,7 @@ public:
 	// tolua_begin
 
 	/** Returns wheter the player can fly or not. */
-	virtual bool CanFly(void) const { return m_CanFly; }
+	virtual bool CanFly(void) const { return m_IsFlightCapable; }
 
 	/** (Re)loads the rank and permissions from the cRankManager.
 	Loads the m_Rank, m_Permissions, m_MsgPrefix, m_MsgSuffix and m_MsgNameColorCode members. */
@@ -541,14 +582,6 @@ public:
 	*/
 	void NotifyNearbyWolves(cPawn * a_Opponent, bool a_IsPlayerInvolved);
 
-	// cEntity overrides:
-	virtual bool IsCrouched (void) const override { return m_IsCrouched; }
-	virtual bool IsSprinting(void) const override { return m_IsSprinting; }
-	virtual bool IsRclking  (void) const override { return IsEating() || IsChargingBow(); }
-
-	virtual void AttachTo(cEntity * a_AttachTo) override;
-	virtual void Detach(void) override;
-
 	/** Returns the progress mined per tick for the block a_Block as a fraction
 	(1 would be completely mined)
 	Depends on hardness values so check those are correct.
@@ -565,18 +598,38 @@ public:
 	If the item is already known, does nothing. */
 	void AddKnownItem(const cItem & a_Item);
 
+	/** Update a player's size, for example, on body stance changes. */
+	void SetSize(float a_Width, float a_Height);
+
 	// cEntity overrides:
+	virtual void AttachTo(cEntity * a_AttachTo) override;
+	virtual void Detach(void) override;
 	virtual cItem GetEquippedWeapon(void) const override { return m_Inventory.GetEquippedItem(); }
 	virtual cItem GetEquippedHelmet(void) const override { return m_Inventory.GetEquippedHelmet(); }
 	virtual cItem GetEquippedChestplate(void) const override { return m_Inventory.GetEquippedChestplate(); }
 	virtual cItem GetEquippedLeggings(void) const override { return m_Inventory.GetEquippedLeggings(); }
 	virtual cItem GetEquippedBoots(void) const override { return m_Inventory.GetEquippedBoots(); }
 	virtual cItem GetOffHandEquipedItem(void) const override { return m_Inventory.GetShieldSlot(); }
+	virtual bool IsCrouched(void) const override;
+	virtual bool IsElytraFlying(void) const override;
+	virtual bool IsOnGround(void) const override { return m_bTouchGround; }
+	virtual bool IsSprinting(void) const override;
 
 private:
 
+	/** Xp Level stuff */
+	enum
+	{
+		XP_TO_LEVEL15 = 255,
+		XP_PER_LEVEL_TO15 = 17,
+		XP_TO_LEVEL30 = 825
+	} ;
+
 	typedef std::vector<std::vector<AString> > AStringVectorVector;
 
+	/** The current body stance the player has adopted. */
+	std::variant<BodyStanceCrouching, BodyStanceSleeping, BodyStanceSprinting, BodyStanceStanding, BodyStanceGliding> m_BodyStance;
+
 	/** The name of the rank assigned to this player. */
 	AString m_Rank;
 
@@ -599,16 +652,6 @@ private:
 	AString m_MsgPrefix, m_MsgSuffix;
 	AString m_MsgNameColorCode;
 
-	/** Xp Level stuff */
-	enum
-	{
-		XP_TO_LEVEL15 = 255,
-		XP_PER_LEVEL_TO15 = 17,
-		XP_TO_LEVEL30 = 825
-	} ;
-
-	bool m_bVisible;
-
 	// Food-related variables:
 	/** Represents the food bar, one point equals half a "drumstick" */
 	int m_FoodLevel;
@@ -622,8 +665,6 @@ private:
 	/** A "buffer" which adds up hunger before it is substracted from m_FoodSaturationLevel or m_FoodLevel. Each action adds a little */
 	double m_FoodExhaustionLevel;
 
-	double m_Stance;
-
 	/** Stores the player's inventory, consisting of crafting grid, hotbar, and main slots */
 	cInventory m_Inventory;
 
@@ -656,12 +697,6 @@ private:
 
 	cSlotNums m_InventoryPaintSlots;
 
-	/** If true, we are locking m_Position to m_FrozenPosition. */
-	bool m_IsFrozen;
-
-	/** Was the player frozen manually by a plugin or automatically by the server? */
-	bool m_IsManuallyFrozen;
-
 	/** Max speed, relative to the game default.
 	1 means regular speed, 2 means twice as fast, 0.5 means half-speed.
 	Default value is 1. */
@@ -677,12 +712,25 @@ private:
 	Default value is 1. */
 	double m_FlyingMaxSpeed;
 
-	bool m_IsCrouched;
+	bool m_IsChargingBow;
-	bool m_IsSprinting;
-	bool m_IsFlying;
 	bool m_IsFishing;
 
-	bool m_CanFly;  // If this is true the player can fly. Even if he is not in creative.
+	/** If this is true the player can fly. Even if he is not in creative. */
+	bool m_IsFlightCapable;
+
+	bool m_IsFlying;
+
+	/** If true, we are locking m_Position to m_FrozenPosition. */
+	bool m_IsFrozen;
+
+	/** Was the player frozen manually by a plugin or automatically by the server? */
+	bool m_IsManuallyFrozen;
+
+	/** Flag used by food handling system to determine whether a teleport has just happened.
+	Will not apply food penalties if found to be true; will set to false after processing. */
+	bool m_IsTeleporting;
+
+	bool m_IsVisible;
 
 	/** The world tick in which eating will be finished. -1 if not eating */
 	Int64 m_EatingFinishTick;
@@ -692,8 +740,7 @@ private:
 	int m_CurrentXp;
 	unsigned int m_EnchantmentSeed;
 
-	bool m_IsChargingBow;
+	int m_BowCharge;
-	int  m_BowCharge;
 
 	UInt32 m_FloaterID;
 
@@ -701,19 +748,10 @@ private:
 
 	cStatManager m_Stats;
 
-	/** Flag representing whether the player is currently in a bed
-	Set by a right click on unoccupied bed, unset by a time fast forward or teleport */
-	bool m_bIsInBed;
-
 	/** How long till the player's inventory will be saved
 	Default save interval is #defined in PLAYER_INVENTORY_SAVE_INTERVAL */
 	unsigned int m_TicksUntilNextSave;
 
-	/** Flag used by food handling system to determine whether a teleport has just happened
-	Will not apply food penalties if found to be true; will set to false after processing
-	*/
-	bool m_bIsTeleporting;
-
 	AString m_CustomName;
 
 	/** Displayed skin part bit mask */
@@ -769,6 +807,7 @@ private:
 	virtual bool DoTakeDamage(TakeDamageInfo & TDI) override;
 	virtual float GetEnchantmentBlastKnockbackReduction() override;
 	virtual void HandlePhysics(std::chrono::milliseconds a_Dt, cChunk &) override { UNUSED(a_Dt); }
+	virtual bool IsRclking(void) const override { return IsEating() || IsChargingBow(); }
 	virtual void OnAddToWorld(cWorld & a_World) override;
 	virtual void OnRemoveFromWorld(cWorld & a_World) override;
 	virtual void SpawnOn(cClientHandle & a_Client) override;

src/Item.cpp

@@ -133,6 +133,7 @@ short cItem::GetMaxDamage(void) const
 		case E_ITEM_DIAMOND_PICKAXE: return 1561;
 		case E_ITEM_DIAMOND_SHOVEL:  return 1561;
 		case E_ITEM_DIAMOND_SWORD:   return 1561;
+		case E_ITEM_ELYTRA:          return 432;
 		case E_ITEM_FLINT_AND_STEEL: return 64;
 		case E_ITEM_FISHING_ROD:     return 65;
 		case E_ITEM_GOLD_AXE:        return 32;

src/Items/ItemArmor.h

@@ -63,14 +63,7 @@ public:
 		}
 
 		a_Player->GetInventory().SetArmorSlot(SlotNum, a_HeldItem.CopyOne());
-
+		a_Player->GetInventory().RemoveOneEquippedItem();
-		cItem Item(a_HeldItem);
-		Item.m_ItemCount--;
-		if (Item.m_ItemCount <= 0)
-		{
-			Item.Empty();
-		}
-		a_Player->GetInventory().SetEquippedItem(Item);
 		return true;
 	}
 
@@ -110,6 +103,7 @@ public:
 			{
 				return (a_ItemType == E_ITEM_GOLD);
 			}
+			case E_ITEM_ELYTRA:  // TODO: require Phantom Membrane instead of leather starting from protocol version 369 or 1.13 release
 			case E_ITEM_LEATHER_BOOTS:
 			case E_ITEM_LEATHER_CAP:
 			case E_ITEM_LEATHER_PANTS:

src/Items/ItemHandler.cpp

@@ -282,6 +282,7 @@ cItemHandler * cItemHandler::CreateItemHandler(int a_ItemType)
 		case E_ITEM_RABBIT_STEW: return new cItemSoupHandler(a_ItemType, FoodInfo(10, 12));
 
 		// Armor:
+		case E_ITEM_ELYTRA:
 		case E_ITEM_LEATHER_CAP:
 		case E_ITEM_GOLD_HELMET:
 		case E_ITEM_CHAIN_HELMET:

src/Protocol/Protocol_1_12.cpp

@@ -349,6 +349,10 @@ void cProtocol_1_12::WriteEntityMetadata(cPacketizer & a_Pkt, const cEntity & a_
 	{
 		Flags |= 0x20;
 	}
+	if (a_Entity.IsElytraFlying())
+	{
+		Flags |= 0x80;
+	}
 	a_Pkt.WriteBEUInt8(ENTITY_FLAGS);  // Index
 	a_Pkt.WriteBEUInt8(METADATA_TYPE_BYTE);  // Type
 	a_Pkt.WriteBEInt8(Flags);

src/Protocol/Protocol_1_8.cpp

@@ -2462,14 +2462,20 @@ void cProtocol_1_8_0::HandlePacketEntityAction(cByteBuffer & a_ByteBuffer)
 	HANDLE_READ(a_ByteBuffer, ReadBEUInt8, UInt8,  Action);
 	HANDLE_READ(a_ByteBuffer, ReadVarInt,  UInt32, JumpBoost);
 
+	if (PlayerID != m_Client->GetPlayer()->GetUniqueID())
+	{
+		m_Client->Kick("Mind your own business! Hacked client?");
+		return;
+	}
+
 	switch (Action)
 	{
-		case 0: m_Client->HandleEntityCrouch(PlayerID, true);     break;  // Crouch
+		case 0: return m_Client->HandleCrouch(true);
-		case 1: m_Client->HandleEntityCrouch(PlayerID, false);    break;  // Uncrouch
+		case 1: return m_Client->HandleCrouch(false);
-		case 2: m_Client->HandleEntityLeaveBed(PlayerID);         break;  // Leave Bed
+		case 2: return m_Client->HandleLeaveBed();
-		case 3: m_Client->HandleEntitySprinting(PlayerID, true);  break;  // Start sprinting
+		case 3: return m_Client->HandleSprint(true);
-		case 4: m_Client->HandleEntitySprinting(PlayerID, false); break;  // Stop sprinting
+		case 4: return m_Client->HandleSprint(false);
-		case 6: m_Client->HandleOpenHorseInventory(PlayerID);     break;  // Open horse inventory
+		case 6: return m_Client->HandleOpenHorseInventory();
 	}
 }
 
@@ -2535,7 +2541,7 @@ void cProtocol_1_8_0::HandlePacketPlayerPos(cByteBuffer & a_ByteBuffer)
 	HANDLE_READ(a_ByteBuffer, ReadBEDouble, double, PosY);
 	HANDLE_READ(a_ByteBuffer, ReadBEDouble, double, PosZ);
 	HANDLE_READ(a_ByteBuffer, ReadBool,     bool,   IsOnGround);
-	m_Client->HandlePlayerPos(PosX, PosY, PosZ, PosY + (m_Client->GetPlayer()->IsCrouched() ? 1.54 : 1.62), IsOnGround);
+	m_Client->HandlePlayerPos(PosX, PosY, PosZ, IsOnGround);
 }
 
 
@@ -2550,7 +2556,7 @@ void cProtocol_1_8_0::HandlePacketPlayerPosLook(cByteBuffer & a_ByteBuffer)
 	HANDLE_READ(a_ByteBuffer, ReadBEFloat,  float,  Yaw);
 	HANDLE_READ(a_ByteBuffer, ReadBEFloat,  float,  Pitch);
 	HANDLE_READ(a_ByteBuffer, ReadBool,     bool,   IsOnGround);
-	m_Client->HandlePlayerMoveLook(PosX, PosY, PosZ, PosY + 1.62, Yaw, Pitch, IsOnGround);
+	m_Client->HandlePlayerMoveLook(PosX, PosY, PosZ, Yaw, Pitch, IsOnGround);
 }
 
 
@@ -3355,6 +3361,10 @@ void cProtocol_1_8_0::WriteEntityMetadata(cPacketizer & a_Pkt, const cEntity & a
 	{
 		Flags |= 0x20;
 	}
+	if (a_Entity.IsElytraFlying())
+	{
+		Flags |= 0x80;
+	}
 	a_Pkt.WriteBEUInt8(0);  // Byte(0) + index 0
 	a_Pkt.WriteBEUInt8(Flags);
 

src/Protocol/Protocol_1_9.cpp

@@ -945,14 +945,21 @@ void cProtocol_1_9_0::HandlePacketEntityAction(cByteBuffer & a_ByteBuffer)
 	HANDLE_READ(a_ByteBuffer, ReadBEUInt8, UInt8,  Action);
 	HANDLE_READ(a_ByteBuffer, ReadVarInt,  UInt32, JumpBoost);
 
+	if (PlayerID != m_Client->GetPlayer()->GetUniqueID())
+	{
+		m_Client->Kick("Mind your own business! Hacked client?");
+		return;
+	}
+
 	switch (Action)
 	{
-		case 0: m_Client->HandleEntityCrouch(PlayerID, true);     break;  // Crouch
+		case 0: return m_Client->HandleCrouch(true);
-		case 1: m_Client->HandleEntityCrouch(PlayerID, false);    break;  // Uncrouch
+		case 1: return m_Client->HandleCrouch(false);
-		case 2: m_Client->HandleEntityLeaveBed(PlayerID);         break;  // Leave Bed
+		case 2: return m_Client->HandleLeaveBed();
-		case 3: m_Client->HandleEntitySprinting(PlayerID, true);  break;  // Start sprinting
+		case 3: return m_Client->HandleSprint(true);
-		case 4: m_Client->HandleEntitySprinting(PlayerID, false); break;  // Stop sprinting
+		case 4: return m_Client->HandleSprint(false);
-		case 7: m_Client->HandleOpenHorseInventory(PlayerID);     break;  // Open horse inventory
+		case 7: return m_Client->HandleOpenHorseInventory();
+		case 8: return m_Client->HandleStartElytraFlight();
 	}
 }
 
@@ -969,7 +976,7 @@ void cProtocol_1_9_0::HandlePacketPlayerPos(cByteBuffer & a_ByteBuffer)
 
 	if (m_IsTeleportIdConfirmed)
 	{
-		m_Client->HandlePlayerPos(PosX, PosY, PosZ, PosY + (m_Client->GetPlayer()->IsCrouched() ? 1.54 : 1.62), IsOnGround);
+		m_Client->HandlePlayerPos(PosX, PosY, PosZ, IsOnGround);
 	}
 }
 
@@ -988,7 +995,7 @@ void cProtocol_1_9_0::HandlePacketPlayerPosLook(cByteBuffer & a_ByteBuffer)
 
 	if (m_IsTeleportIdConfirmed)
 	{
-		m_Client->HandlePlayerMoveLook(PosX, PosY, PosZ, PosY + 1.62, Yaw, Pitch, IsOnGround);
+		m_Client->HandlePlayerMoveLook(PosX, PosY, PosZ, Yaw, Pitch, IsOnGround);
 	}
 }
 
@@ -1666,6 +1673,10 @@ void cProtocol_1_9_0::WriteEntityMetadata(cPacketizer & a_Pkt, const cEntity & a
 	{
 		Flags |= 0x20;
 	}
+	if (a_Entity.IsElytraFlying())
+	{
+		Flags |= 0x80;
+	}
 	a_Pkt.WriteBEUInt8(0);  // Index 0
 	a_Pkt.WriteBEUInt8(METADATA_TYPE_BYTE);  // Type
 	a_Pkt.WriteBEInt8(Flags);

src/World.h

@@ -33,16 +33,7 @@ class cPlayer;
 class cClientHandle;
 class cEntity;
 class cChunkGenerator;  // The thread responsible for generating chunks
-class cBeaconEntity;
-class cBrewingstandEntity;
-class cChestEntity;
 class cCuboid;
-class cDispenserEntity;
-class cFlowerPotEntity;
-class cFurnaceEntity;
-class cHopperEntity;
-class cNoteEntity;
-class cMobHeadEntity;
 class cCompositeChat;
 class cDeadlockDetect;
 class cUUID;