cuberite-2a/src/ChunkMap.h

// cChunkMap.h

// Interfaces to the cChunkMap class representing the chunk storage for a single world

#pragma once


#include "ChunkDataCallback.h"





class cWorld;
class cWorldInterface;
class cItem;
class MTRand;
class cChunkStay;
class cChunk;
class cPlayer;
class cChestEntity;
class cDispenserEntity;
class cDropperEntity;
class cDropSpenserEntity;
class cFurnaceEntity;
class cNoteEntity;
class cCommandBlockEntity;
class cMobHeadEntity;
class cFlowerPotEntity;
class cPawn;
class cPickup;
class cChunkDataSerializer;
class cBlockArea;
class cMobCensus;
class cMobSpawner;

typedef std::list<cClientHandle *>         cClientHandleList;
typedef cChunk *                           cChunkPtr;
typedef cItemCallback<cEntity>             cEntityCallback;
typedef cItemCallback<cBlockEntity>        cBlockEntityCallback;
typedef cItemCallback<cChestEntity>        cChestCallback;
typedef cItemCallback<cDispenserEntity>    cDispenserCallback;
typedef cItemCallback<cDropperEntity>      cDropperCallback;
typedef cItemCallback<cDropSpenserEntity>  cDropSpenserCallback;
typedef cItemCallback<cFlowerPotEntity>    cFlowerPotCallback;
typedef cItemCallback<cFurnaceEntity>      cFurnaceCallback;
typedef cItemCallback<cNoteEntity>         cNoteBlockCallback;
typedef cItemCallback<cCommandBlockEntity> cCommandBlockCallback;
typedef cItemCallback<cMobHeadEntity>      cMobHeadCallback;
typedef cItemCallback<cChunk>              cChunkCallback;





class cChunkMap
{
public:

	static const int LAYER_SIZE = 32;

	cChunkMap(cWorld* a_World );
	~cChunkMap();

	// Broadcast respective packets to all clients of the chunk where the event is taking place
	// (Please keep these alpha-sorted)
	void BroadcastAttachEntity(const cEntity & a_Entity, const cEntity * a_Vehicle);
	void BroadcastBlockAction(int a_BlockX, int a_BlockY, int a_BlockZ, char a_Byte1, char a_Byte2, BLOCKTYPE a_BlockType, const cClientHandle * a_Exclude = NULL);
	void BroadcastBlockBreakAnimation(int a_entityID, int a_blockX, int a_blockY, int a_blockZ, char a_stage, const cClientHandle * a_Exclude = NULL);
	void BroadcastBlockEntity(int a_BlockX, int a_BlockY, int a_BlockZ, const cClientHandle * a_Exclude);
	void BroadcastChunkData(int a_ChunkX, int a_ChunkZ, cChunkDataSerializer & a_Serializer, const cClientHandle * a_Exclude = NULL);
	void BroadcastCollectEntity(const cEntity & a_Entity, const cPlayer & a_Player, const cClientHandle * a_Exclude = NULL);
	void BroadcastCollectPickup(const cPickup & a_Pickup, const cPlayer & a_Player, const cClientHandle * a_Exclude = NULL);
	void BroadcastDestroyEntity(const cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityEffect(const cEntity & a_Entity, int a_EffectID, int a_Amplifier, short a_Duration, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityEquipment(const cEntity & a_Entity, short a_SlotNum, const cItem & a_Item, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityHeadLook(const cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityLook(const cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityMetadata(const cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityRelMove(const cEntity & a_Entity, char a_RelX, char a_RelY, char a_RelZ, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityRelMoveLook(const cEntity & a_Entity, char a_RelX, char a_RelY, char a_RelZ, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityStatus(const cEntity & a_Entity, char a_Status, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityVelocity(const cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastEntityAnimation(const cEntity & a_Entity, char a_Animation, const cClientHandle * a_Exclude = NULL);
	void BroadcastParticleEffect(const AString & a_ParticleName, float a_SrcX, float a_SrcY, float a_SrcZ, float a_OffsetX, float a_OffsetY, float a_OffsetZ, float a_ParticleData, int a_ParticleAmmount, cClientHandle * a_Exclude = NULL);
	void BroadcastRemoveEntityEffect (const cEntity & a_Entity, int a_EffectID, const cClientHandle * a_Exclude = NULL);
	void BroadcastSoundEffect(const AString & a_SoundName, int a_SrcX, int a_SrcY, int a_SrcZ, float a_Volume, float a_Pitch, const cClientHandle * a_Exclude = NULL);   // a_Src coords are Block * 8
	void BroadcastSoundParticleEffect(int a_EffectID, int a_SrcX, int a_SrcY, int a_SrcZ, int a_Data, const cClientHandle * a_Exclude = NULL);
	void BroadcastSpawnEntity(cEntity & a_Entity, const cClientHandle * a_Exclude = NULL);
	void BroadcastThunderbolt(int a_BlockX, int a_BlockY, int a_BlockZ, const cClientHandle * a_Exclude = NULL);
	void BroadcastUseBed(const cEntity & a_Entity, int a_BlockX, int a_BlockY, int a_BlockZ );
	
	/** Sends the block entity, if it is at the coords specified, to a_Client */
	void SendBlockEntity(int a_BlockX, int a_BlockY, int a_BlockZ, cClientHandle & a_Client);
	
	/** a_Player rclked block entity at the coords specified, handle it */
	void UseBlockEntity(cPlayer * a_Player, int a_X, int a_Y, int a_Z);
	
	/** Calls the callback for the chunk specified, with ChunkMapCS locked; returns false if the chunk doesn't exist, otherwise returns the same value as the callback */
	bool DoWithChunk(int a_ChunkX, int a_ChunkZ, cChunkCallback & a_Callback);

	/** Wakes up simulators for the specified block */
	void WakeUpSimulators(int a_BlockX, int a_BlockY, int a_BlockZ);

	/** Wakes up the simulators for the specified area of blocks */
	void WakeUpSimulatorsInArea(int a_MinBlockX, int a_MaxBlockX, int a_MinBlockY, int a_MaxBlockY, int a_MinBlockZ, int a_MaxBlockZ);

	void MarkChunkDirty     (int a_ChunkX, int a_ChunkZ);
	void MarkChunkSaving    (int a_ChunkX, int a_ChunkZ);
	void MarkChunkSaved     (int a_ChunkX, int a_ChunkZ);
	
	/** Sets the chunk data as either loaded from the storage or generated.
	a_BlockLight and a_BlockSkyLight are optional, if not present, chunk will be marked as unlighted.
	a_BiomeMap is optional, if not present, biomes will be calculated by the generator
	a_HeightMap is optional, if not present, will be calculated.
	If a_MarkDirty is set, the chunk is set as dirty (used after generating)
	*/
	void SetChunkData(
		int a_ChunkX, int a_ChunkZ, 
		const BLOCKTYPE * a_BlockTypes,
		const NIBBLETYPE * a_BlockMeta,
		const NIBBLETYPE * a_BlockLight,
		const NIBBLETYPE * a_BlockSkyLight,
		const cChunkDef::HeightMap * a_HeightMap,
		const cChunkDef::BiomeMap &  a_BiomeMap,
		cBlockEntityList & a_BlockEntities,
		bool a_MarkDirty
	);
	
	void ChunkLighted(
		int a_ChunkX, int a_ChunkZ,
		const cChunkDef::BlockNibbles & a_BlockLight,
		const cChunkDef::BlockNibbles & a_SkyLight
	);
	
	bool GetChunkData       (int a_ChunkX, int a_ChunkZ, cChunkDataCallback & a_Callback);
	
	/** Copies the chunk's blocktypes into a_Blocks; returns true if successful */
	bool GetChunkBlockTypes (int a_ChunkX, int a_ChunkZ, BLOCKTYPE * a_Blocks);
	
	bool      IsChunkValid       (int a_ChunkX, int a_ChunkZ);
	bool      HasChunkAnyClients (int a_ChunkX, int a_ChunkZ);
	int       GetHeight          (int a_BlockX, int a_BlockZ);  // Waits for the chunk to get loaded / generated
	bool      TryGetHeight       (int a_BlockX, int a_BlockZ, int & a_Height);  // Returns false if chunk not loaded / generated
	void FastSetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
	
	void FastSetQueuedBlocks();
	void      FastSetBlocks      (sSetBlockList & a_BlockList);
	void      CollectPickupsByPlayer(cPlayer * a_Player);
	
	BLOCKTYPE  GetBlock          (int a_BlockX, int a_BlockY, int a_BlockZ);
	NIBBLETYPE GetBlockMeta      (int a_BlockX, int a_BlockY, int a_BlockZ);
	NIBBLETYPE GetBlockSkyLight  (int a_BlockX, int a_BlockY, int a_BlockZ);
	NIBBLETYPE GetBlockBlockLight(int a_BlockX, int a_BlockY, int a_BlockZ);
	void       SetBlockMeta      (int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockMeta);
	void       SetBlock          (cWorldInterface & a_WorldInterface, int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, BLOCKTYPE a_BlockMeta, bool a_SendToClients = true);
	void       QueueSetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, BLOCKTYPE a_BlockMeta, Int64 a_Tick, BLOCKTYPE a_PreviousBlockType = E_BLOCK_AIR);
	bool       GetBlockTypeMeta  (int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta);
	bool       GetBlockInfo      (int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_Meta, NIBBLETYPE & a_SkyLight, NIBBLETYPE & a_BlockLight);

	/** Replaces world blocks with a_Blocks, if they are of type a_FilterBlockType */
	void      ReplaceBlocks(const sSetBlockVector & a_Blocks, BLOCKTYPE a_FilterBlockType);
	
	/** Special function used for growing trees, replaces only blocks that tree may overwrite */
	void      ReplaceTreeBlocks(const sSetBlockVector & a_Blocks);
	
	/** Returns the biome at the specified coords. Reads the biome from the chunk, if loaded, otherwise uses the world generator to provide the biome value */
	EMCSBiome GetBiomeAt (int a_BlockX, int a_BlockZ);
	
	/** Sets the biome at the specified coords. Returns true if successful, false if not (chunk not loaded).
	Doesn't resend the chunk to clients. */
	bool SetBiomeAt(int a_BlockX, int a_BlockZ, EMCSBiome a_Biome);
	
	/** Sets the biome at the area. Returns true if successful, false if any subarea failed (chunk not loaded).
	(Re)sends the chunks to their relevant clients if successful. */
	bool SetAreaBiome(int a_MinX, int a_MaxX, int a_MinZ, int a_MaxZ, EMCSBiome a_Biome);
	
	/** Retrieves block types of the specified blocks. If a chunk is not loaded, doesn't modify the block. Returns true if all blocks were read. */
	bool GetBlocks(sSetBlockVector & a_Blocks, bool a_ContinueOnFailure);

	bool DigBlock   (int a_X, int a_Y, int a_Z);
	void SendBlockTo(int a_X, int a_Y, int a_Z, cPlayer * a_Player);
	
	/** Compares clients of two chunks, calls the callback accordingly */
	void CompareChunkClients(int a_ChunkX1, int a_ChunkZ1, int a_ChunkX2, int a_ChunkZ2, cClientDiffCallback & a_Callback);
	
	/** Compares clients of two chunks, calls the callback accordingly */
	void CompareChunkClients(cChunk * a_Chunk1, cChunk * a_Chunk2, cClientDiffCallback & a_Callback);

	/** Adds client to a chunk, if not already present; returns true if added, false if present */
	bool AddChunkClient(int a_ChunkX, int a_ChunkZ, cClientHandle * a_Client);

	/** Removes the client from the chunk */
	void RemoveChunkClient(int a_ChunkX, int a_ChunkZ, cClientHandle * a_Client);
	
	/** Removes the client from all chunks it is present in */
	void RemoveClientFromChunks(cClientHandle * a_Client);

	/** Adds the entity to its appropriate chunk, takes ownership of the entity pointer */
	void AddEntity(cEntity * a_Entity);
	
	/** Adds the entity to its appropriate chunk, if the entity is not already added.
	Takes ownership of the entity pointer */
	void AddEntityIfNotPresent(cEntity * a_Entity);
	
	/** Returns true if the entity with specified ID is present in the chunks */
	bool HasEntity(int a_EntityID);
	
	/** Removes the entity from its appropriate chunk */
	void RemoveEntity(cEntity * a_Entity);
	
	/** Calls the callback for each entity in the entire world; returns true if all entities processed, false if the callback aborted by returning true */
	bool ForEachEntity(cEntityCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for each entity in the specified chunk; returns true if all entities processed, false if the callback aborted by returning true */
	bool ForEachEntityInChunk(int a_ChunkX, int a_ChunkZ, cEntityCallback & a_Callback);  // Lua-accessible

	/** Destroys and returns a list of blocks destroyed in the explosion at the specified coordinates */
	void DoExplosionAt(double a_ExplosionSize, double a_BlockX, double a_BlockY, double a_BlockZ, cVector3iArray & a_BlockAffected);
	
	/** Calls the callback if the entity with the specified ID is found, with the entity object as the callback param. Returns true if entity found and callback returned false. */
	bool DoWithEntityByID(int a_UniqueID, cEntityCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for each block entity in the specified chunk; returns true if all block entities processed, false if the callback aborted by returning true */
	bool ForEachBlockEntityInChunk(int a_ChunkX, int a_ChunkZ, cBlockEntityCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for each chest in the specified chunk; returns true if all chests processed, false if the callback aborted by returning true */
	bool ForEachChestInChunk(int a_ChunkX, int a_ChunkZ, cChestCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for each dispenser in the specified chunk; returns true if all dispensers processed, false if the callback aborted by returning true */
	bool ForEachDispenserInChunk(int a_ChunkX, int a_ChunkZ, cDispenserCallback & a_Callback);

	/** Calls the callback for each dropper in the specified chunk; returns true if all droppers processed, false if the callback aborted by returning true */
	bool ForEachDropperInChunk(int a_ChunkX, int a_ChunkZ, cDropperCallback & a_Callback);

	/** Calls the callback for each dropspenser in the specified chunk; returns true if all dropspensers processed, false if the callback aborted by returning true */
	bool ForEachDropSpenserInChunk(int a_ChunkX, int a_ChunkZ, cDropSpenserCallback & a_Callback);

	/** Calls the callback for each furnace in the specified chunk; returns true if all furnaces processed, false if the callback aborted by returning true */
	bool ForEachFurnaceInChunk(int a_ChunkX, int a_ChunkZ, cFurnaceCallback & a_Callback);  // Lua-accessible
	
	/** Calls the callback for the block entity at the specified coords; returns false if there's no block entity at those coords, true if found */
	bool DoWithBlockEntityAt(int a_BlockX, int a_BlockY, int a_BlockZ, cBlockEntityCallback & a_Callback);  // Lua-acessible

	/** Calls the callback for the chest at the specified coords; returns false if there's no chest at those coords, true if found */
	bool DoWithChestAt(int a_BlockX, int a_BlockY, int a_BlockZ, cChestCallback & a_Callback);  // Lua-acessible

	/** Calls the callback for the dispenser at the specified coords; returns false if there's no dispenser at those coords or callback returns true, returns true if found */
	bool DoWithDispenserAt(int a_BlockX, int a_BlockY, int a_BlockZ, cDispenserCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the dropper at the specified coords; returns false if there's no dropper at those coords or callback returns true, returns true if found */
	bool DoWithDropperAt(int a_BlockX, int a_BlockY, int a_BlockZ, cDropperCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the dropspenser at the specified coords; returns false if there's no dropspenser at those coords or callback returns true, returns true if found */
	bool DoWithDropSpenserAt(int a_BlockX, int a_BlockY, int a_BlockZ, cDropSpenserCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the furnace at the specified coords; returns false if there's no furnace at those coords or callback returns true, returns true if found */
	bool DoWithFurnaceAt(int a_BlockX, int a_BlockY, int a_BlockZ, cFurnaceCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the noteblock at the specified coords; returns false if there's no noteblock at those coords or callback returns true, returns true if found */
	bool DoWithNoteBlockAt(int a_BlockX, int a_BlockY, int a_BlockZ, cNoteBlockCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the command block at the specified coords; returns false if there's no command block at those coords or callback returns true, returns true if found */
	bool DoWithCommandBlockAt(int a_BlockX, int a_BlockY, int a_BlockZ, cCommandBlockCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the mob head block at the specified coords; returns false if there's no mob head block at those coords or callback returns true, returns true if found */
	bool DoWithMobHeadAt(int a_BlockX, int a_BlockY, int a_BlockZ, cMobHeadCallback & a_Callback);  // Lua-accessible

	/** Calls the callback for the flower pot at the specified coords; returns false if there's no flower pot at those coords or callback returns true, returns true if found */
	bool DoWithFlowerPotAt(int a_BlockX, int a_BlockY, int a_BlockZ, cFlowerPotCallback & a_Callback);  // Lua-accessible

	/** Retrieves the test on the sign at the specified coords; returns false if there's no sign at those coords, true if found */
	bool GetSignLines (int a_BlockX, int a_BlockY, int a_BlockZ, AString & a_Line1, AString & a_Line2, AString & a_Line3, AString & a_Line4);  // Lua-accessible

	/** Touches the chunk, causing it to be loaded or generated */
	void TouchChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
	
	/** Loads the chunk, if not already loaded. Doesn't generate. Returns true if chunk valid (even if already loaded before) */
	bool LoadChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
	
	/** Loads the chunks specified. Doesn't report failure, other than chunks being !IsValid() */
	void LoadChunks(const cChunkCoordsList & a_Chunks);

	/** Marks the chunk as failed-to-load */
	void ChunkLoadFailed(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
	
	/** Sets the sign text. Returns true if sign text changed. */
	bool SetSignLines(int a_BlockX, int a_BlockY, int a_BlockZ, const AString & a_Line1, const AString & a_Line2, const AString & a_Line3, const AString & a_Line4);
	
	/** Marks the chunk as being regenerated - all its clients want that chunk again (used by cWorld::RegenerateChunk() ) */
	void MarkChunkRegenerating(int a_ChunkX, int a_ChunkZ);
	
	bool IsChunkLighted(int a_ChunkX, int a_ChunkZ);
	
	/** Calls the callback for each chunk in the coords specified (all cords are inclusive). Returns true if all chunks have been processed successfully */
	bool ForEachChunkInRect(int a_MinChunkX, int a_MaxChunkX, int a_MinChunkZ, int a_MaxChunkZ, cChunkDataCallback & a_Callback);
	
	/** Writes the block area into the specified coords. Returns true if all chunks have been processed. Prefer cBlockArea::Write() instead. */
	bool WriteBlockArea(cBlockArea & a_Area, int a_MinBlockX, int a_MinBlockY, int a_MinBlockZ, int a_DataTypes);

	/** Returns the number of valid chunks and the number of dirty chunks */
	void GetChunkStats(int & a_NumChunksValid, int & a_NumChunksDirty);
	
	/** Grows a melon or a pumpkin next to the block specified (assumed to be the stem) */
	void GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, MTRand & a_Rand);
	
	/** Grows a sugarcane present at the block specified by the amount of blocks specified, up to the max height specified in the config */
	void GrowSugarcane(int a_BlockX, int a_BlockY, int a_BlockZ, int a_NumBlocksToGrow);
	
	/** Grows a cactus present at the block specified by the amount of blocks specified, up to the max height specified in the config */
	void GrowCactus(int a_BlockX, int a_BlockY, int a_BlockZ, int a_NumBlocksToGrow);
	
	/** Sets the blockticking to start at the specified block. Only one blocktick per chunk may be set, second call overwrites the first call */
	void SetNextBlockTick(int a_BlockX, int a_BlockY, int a_BlockZ);

	/** Make a Mob census, of all mobs, their family, their chunk and theyr distance to closest player */
	void CollectMobCensus(cMobCensus& a_ToFill);

	/** Try to Spawn Monsters inside all Chunks */
	void SpawnMobs(cMobSpawner& a_MobSpawner);

	void Tick(float a_Dt);
	
	/** Ticks a single block. Used by cWorld::TickQueuedBlocks() to tick the queued blocks */
	void TickBlock(int a_BlockX, int a_BlockY, int a_BlockZ);

	void UnloadUnusedChunks(void);
	void SaveAllChunks(void);

	cWorld * GetWorld(void) { return m_World; }

	int GetNumChunks(void);
	
	void ChunkValidated(void);  // Called by chunks that have become valid
	
	/** Queues the specified block for ticking (block update) */
	void QueueTickBlock(int a_BlockX, int a_BlockY, int a_BlockZ);
	
	/** Returns the CS for locking the chunkmap; only cWorld::cLock may use this function! */
	cCriticalSection & GetCS(void) { return m_CSLayers; }

private:

	// The chunks can manipulate neighbors while in their Tick() method, using LockedGetBlock() and LockedSetBlock()
	friend class cChunk;
	
	// The chunkstay can (de-)register itself using AddChunkStay() and DelChunkStay()
	friend class cChunkStay;
	

	class cChunkLayer
	{
	public:
		cChunkLayer(
			int a_LayerX, int a_LayerZ, 
			cChunkMap * a_Parent,
			cAllocationPool<cChunkData::sChunkSection> & a_Pool
		);
		~cChunkLayer();

		/** Always returns an assigned chunkptr, but the chunk needn't be valid (loaded / generated) - callers must check */
		cChunkPtr GetChunk( int a_ChunkX, int a_ChunkY, int a_ChunkZ );
		
		/** Returns the specified chunk, or NULL if not created yet */
		cChunk * FindChunk(int a_ChunkX, int a_ChunkZ);
		
		int GetX(void) const {return m_LayerX; }
		int GetZ(void) const {return m_LayerZ; }
		
		int GetNumChunksLoaded(void) const ;
		
		void GetChunkStats(int & a_NumChunksValid, int & a_NumChunksDirty) const;
		
		void Save(void);
		void UnloadUnusedChunks(void);
		
		/** Collect a mob census, of all mobs, their megatype, their chunk and their distance o closest player */
		void CollectMobCensus(cMobCensus& a_ToFill);		
		/** Try to Spawn Monsters inside all Chunks */
		void SpawnMobs(cMobSpawner& a_MobSpawner);

		void Tick(float a_Dt);
		
		void RemoveClient(cClientHandle * a_Client);
		
		/** Calls the callback for each entity in the entire world; returns true if all entities processed, false if the callback aborted by returning true */
		bool ForEachEntity(cEntityCallback & a_Callback);  // Lua-accessible

		/** Calls the callback if the entity with the specified ID is found, with the entity object as the callback param. Returns true if entity found. */
		bool DoWithEntityByID(int a_EntityID, cEntityCallback & a_Callback, bool & a_CallbackReturn);  // Lua-accessible

		/** Returns true if there is an entity with the specified ID within this layer's chunks */
		bool HasEntity(int a_EntityID);
		
	protected:
	
		cChunkPtr m_Chunks[LAYER_SIZE * LAYER_SIZE];
		int m_LayerX;
		int m_LayerZ;
		cChunkMap * m_Parent;
		int m_NumChunksLoaded;
		
		cAllocationPool<cChunkData::sChunkSection> & m_Pool;
	};
	
	class cStarvationCallbacks
		: public cAllocationPool<cChunkData::sChunkSection>::cStarvationCallbacks
	{
		virtual void OnStartUsingReserve() override
		{
			LOG("Using backup memory buffer");
		}
		virtual void OnEndUsingReserve() override
		{
			LOG("Stoped using backup memory buffer");
		}
		virtual void OnOutOfReserve() override
		{
			LOG("Out of Memory");
		}
	};
	
	typedef std::list<cChunkLayer *> cChunkLayerList;
	
	typedef std::list<cChunkStay *> cChunkStays;

	/** Finds the cChunkLayer object responsible for the specified chunk; returns NULL if not found. Assumes m_CSLayers is locked. */
	cChunkLayer * FindLayerForChunk(int a_ChunkX, int a_ChunkZ);
	
	/** Returns the specified cChunkLayer object; returns NULL if not found. Assumes m_CSLayers is locked. */
	cChunkLayer * FindLayer(int a_LayerX, int a_LayerZ);
	
	/** Returns the cChunkLayer object responsible for the specified chunk; creates it if not found. */
	cChunkLayer * GetLayerForChunk (int a_ChunkX, int a_ChunkZ);
	
	/** Returns the specified cChunkLayer object; creates it if not found. */
	cChunkLayer * GetLayer(int a_LayerX, int a_LayerZ);
	
	void RemoveLayer(cChunkLayer * a_Layer);

	cCriticalSection m_CSLayers;
	cChunkLayerList  m_Layers;
	cEvent           m_evtChunkValid;  // Set whenever any chunk becomes valid, via ChunkValidated()

	cWorld * m_World;
	
	cCriticalSection m_CSFastSetBlock;
	sSetBlockList    m_FastSetBlockQueue;
	
	/** The cChunkStay descendants that are currently enabled in this chunkmap */
	cChunkStays m_ChunkStays;

	std::auto_ptr<cAllocationPool<cChunkData::sChunkSection> > m_Pool;

	cChunkPtr GetChunk      (int a_ChunkX, int a_ChunkY, int a_ChunkZ);  // Also queues the chunk for loading / generating if not valid
	cChunkPtr GetChunkNoGen (int a_ChunkX, int a_ChunkY, int a_ChunkZ);  // Also queues the chunk for loading if not valid; doesn't generate
	cChunkPtr GetChunkNoLoad(int a_ChunkX, int a_ChunkY, int a_ChunkZ);  // Doesn't load, doesn't generate
	
	/** Gets a block in any chunk while in the cChunk's Tick() method; returns true if successful, false if chunk not loaded (doesn't queue load) */
	bool LockedGetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta);
	
	/** Gets a block type in any chunk while in the cChunk's Tick() method; returns true if successful, false if chunk not loaded (doesn't queue load) */
	bool LockedGetBlockType(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE & a_BlockType);
	
	/** Gets a block meta in any chunk while in the cChunk's Tick() method; returns true if successful, false if chunk not loaded (doesn't queue load) */
	bool LockedGetBlockMeta(int a_BlockX, int a_BlockY, int a_BlockZ, NIBBLETYPE & a_BlockMeta);
	
	/** Sets a block in any chunk while in the cChunk's Tick() method; returns true if successful, false if chunk not loaded (doesn't queue load) */
	bool LockedSetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);

	/** Fast-sets a block in any chunk while in the cChunk's Tick() method; returns true if successful, false if chunk not loaded (doesn't queue load) */
	bool LockedFastSetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
	
	/** Locates a chunk ptr in the chunkmap; doesn't create it when not found; assumes m_CSLayers is locked. To be called only from cChunkMap. */
	cChunk * FindChunk(int a_ChunkX, int a_ChunkZ);

	/** Adds a new cChunkStay descendant to the internal list of ChunkStays; loads its chunks.
	To be used only by cChunkStay; others should use cChunkStay::Enable() instead */
	void AddChunkStay(cChunkStay & a_ChunkStay);
	
	/** Removes the specified cChunkStay descendant from the internal list of ChunkStays.
	To be used only by cChunkStay; others should use cChunkStay::Disable() instead */
	void DelChunkStay(cChunkStay & a_ChunkStay);
	
};