From b904223b9dbbe7b696dbd30e748bc131742e11ea Mon Sep 17 00:00:00 2001
From: Mattes D <github@xoft.cz>
Date: Fri, 6 Jun 2014 22:31:16 +0200
Subject: [PATCH] Added queue for adding entities to cWorld.

This alone doesn't work properly yet, further changes to cPlayer are needed.
---
 src/ClientHandle.h      |  3 ++-
 src/Entities/Entity.h   |  5 +++--
 src/Entities/Player.cpp |  2 --
 src/Entities/Player.h   |  2 ++
 src/World.cpp           | 28 +++++++++++++++++++++++++++-
 src/World.h             |  9 ++++++++-
 6 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/src/ClientHandle.h b/src/ClientHandle.h
index 659c67658..3f1cdf55a 100644
--- a/src/ClientHandle.h
+++ b/src/ClientHandle.h
@@ -250,7 +250,8 @@ public:
 	
 	void SendData(const char * a_Data, size_t a_Size);
 	
-	/** Called when the player moves into a different world; queues sreaming the new chunks */
+	/** Called when the player moves into a different world.
+	Locks the current world, doesn't lock the new world. */
 	void MoveToWorld(cWorld & a_World, bool a_SendRespawnPacket);
 	
 	/** Called when the player will enchant a Item */
diff --git a/src/Entities/Entity.h b/src/Entities/Entity.h
index 0c393c0f5..9fe771120 100644
--- a/src/Entities/Entity.h
+++ b/src/Entities/Entity.h
@@ -421,6 +421,9 @@ public:
 		UNUSED(a_Killer);
 	}
 
+	/** Sets the internal world pointer to a new cWorld, doesn't update anything else. */
+	void SetWorld(cWorld * a_World) { m_World = a_World; }
+
 protected:
 	static cCriticalSection m_CSCount;
 	static int m_EntityCount;
@@ -485,8 +488,6 @@ protected:
 
 	virtual void Destroyed(void) {} // Called after the entity has been destroyed
 
-	void SetWorld(cWorld * a_World) { m_World = a_World; }
-
 	/** Called in each tick to handle air-related processing i.e. drowning */
 	virtual void HandleAir();
 	
diff --git a/src/Entities/Player.cpp b/src/Entities/Player.cpp
index 3a9324d09..b83419903 100644
--- a/src/Entities/Player.cpp
+++ b/src/Entities/Player.cpp
@@ -1595,8 +1595,6 @@ bool cPlayer::MoveToWorld(const char * a_WorldName)
 	m_ClientHandle->MoveToWorld(*World, (OldDimension != World->GetDimension()));
 
 	// Add player to all the necessary parts of the new world
-	SetWorld(World);
-	m_ClientHandle->StreamChunks();
 	World->AddEntity(this);
 	World->AddPlayer(this);
 
diff --git a/src/Entities/Player.h b/src/Entities/Player.h
index b7cb27d6c..83b9ad593 100644
--- a/src/Entities/Player.h
+++ b/src/Entities/Player.h
@@ -328,6 +328,8 @@ public:
 	void SetVisible( bool a_bVisible );										// tolua_export
 	bool IsVisible(void) const { return m_bVisible; }									// tolua_export
 
+	/** Moves the player to the specified world.
+	Returns true if successful, false on failure (world not found). */
 	bool MoveToWorld(const char * a_WorldName);  // tolua_export
 
 	bool SaveToDisk(void);
diff --git a/src/World.cpp b/src/World.cpp
index 88e9c32e6..ccd47d3b0 100644
--- a/src/World.cpp
+++ b/src/World.cpp
@@ -743,6 +743,17 @@ void cWorld::Tick(float a_Dt, int a_LastTickDurationMSec)
 		m_LastTimeUpdate = m_WorldAge;
 	}
 
+	// Add entities waiting in the queue to be added:
+	{
+		cCSLock Lock(m_CSEntitiesToAdd);
+		for (cEntityList::iterator itr = m_EntitiesToAdd.begin(), end = m_EntitiesToAdd.end(); itr != end; ++itr)
+		{
+			(*itr)->SetWorld(this);
+			m_ChunkMap->AddEntity(*itr);
+		}
+		m_EntitiesToAdd.clear();
+	}
+
 	m_ChunkMap->Tick(a_Dt);
 
 	TickClients(a_Dt);
@@ -2808,9 +2819,11 @@ void cWorld::ScheduleTask(int a_DelayTicks, cTask * a_Task)
 
 
 
+
 void cWorld::AddEntity(cEntity * a_Entity)
 {
-	m_ChunkMap->AddEntity(a_Entity);
+	cCSLock Lock(m_CSEntitiesToAdd);
+	m_EntitiesToAdd.push_back(a_Entity);
 }
 
 
@@ -2819,6 +2832,19 @@ void cWorld::AddEntity(cEntity * a_Entity)
 
 bool cWorld::HasEntity(int a_UniqueID)
 {
+	// Check if the entity is in the queue to be added to the world:
+	{
+		cCSLock Lock(m_CSEntitiesToAdd);
+		for (cEntityList::const_iterator itr = m_EntitiesToAdd.begin(), end = m_EntitiesToAdd.end(); itr != end; ++itr)
+		{
+			if ((*itr)->GetUniqueID() == a_UniqueID)
+			{
+				return true;
+			}
+		}  // for itr - m_EntitiesToAdd[]
+	}
+
+	// Check if the entity is in the chunkmap:
 	return m_ChunkMap->HasEntity(a_UniqueID);
 }
 
diff --git a/src/World.h b/src/World.h
index 98b241a2b..4c014a976 100644
--- a/src/World.h
+++ b/src/World.h
@@ -301,7 +301,8 @@ public:
 	
 	void SendPlayerList(cPlayer * a_DestPlayer);  // Sends playerlist to the player
 
-	/** Adds the entity into its appropriate chunk; takes ownership of the entity ptr */
+	/** Adds the entity into its appropriate chunk; takes ownership of the entity ptr.
+	The entity is added lazily - this function only puts it in a queue that is then processed by the Tick thread. */
 	void AddEntity(cEntity * a_Entity);
 	
 	bool HasEntity(int a_UniqueID);
@@ -926,6 +927,12 @@ private:
 	/** Clients that are scheduled for adding, waiting for TickClients to add them */
 	cClientHandleList m_ClientsToAdd;
 
+	/** Guards m_EntitiesToAdd */
+	cCriticalSection m_CSEntitiesToAdd;
+
+	/** List of entities that are scheduled for adding, waiting for the Tick thread to add them. */
+	cEntityList m_EntitiesToAdd;
+
 
 	cWorld(const AString & a_WorldName);
 	virtual ~cWorld();