4 files changed, 224 insertions, 13 deletions

diff --git a/source/Chunk.cpp b/source/Chunk.cpp
index f297e0bbd..5bfe28e41 100644
--- a/source/Chunk.cpp
+++ b/source/Chunk.cpp
@@ -55,7 +55,11 @@ sSetBlock::sSetBlock( int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_Bloc
 ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 // cChunk:
 
-cChunk::cChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ, cChunkMap * a_ChunkMap, cWorld * a_World)
+cChunk::cChunk(
+	int a_ChunkX, int a_ChunkY, int a_ChunkZ, 
+	cChunkMap * a_ChunkMap, cWorld * a_World,
+	cChunk * a_NeighborXM, cChunk * a_NeighborXP, cChunk * a_NeighborZM, cChunk * a_NeighborZP
+)
 	: m_PosX( a_ChunkX )
 	, m_PosY( a_ChunkY )
 	, m_PosZ( a_ChunkZ )
@@ -69,8 +73,27 @@ cChunk::cChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ, cChunkMap * a_ChunkMap,
 	, m_IsDirty(false)
 	, m_IsSaving(false)
 	, m_StayCount(0)
+	, m_NeighborXM(a_NeighborXM)
+	, m_NeighborXP(a_NeighborXP)
+	, m_NeighborZM(a_NeighborZM)
+	, m_NeighborZP(a_NeighborZP)
 {
-	// LOGINFO("### new cChunk (%i, %i) at %p, thread 0x%x ###", a_X, a_Z, this, GetCurrentThreadId());
+	if (a_NeighborXM != NULL)
+	{
+		a_NeighborXM->m_NeighborXP = this;
+	}
+	if (a_NeighborXP != NULL)
+	{
+		a_NeighborXP->m_NeighborXM = this;
+	}
+	if (a_NeighborZM != NULL)
+	{
+		a_NeighborZM->m_NeighborZP = this;
+	}
+	if (a_NeighborZP != NULL)
+	{
+		a_NeighborZP->m_NeighborZM = this;
+	}
 }
 
 
@@ -102,6 +125,23 @@ cChunk::~cChunk()
 		(*itr)->Destroy();
 	}
 	m_Entities.clear();
+	
+	if (m_NeighborXM != NULL)
+	{
+		m_NeighborXM->m_NeighborXP = NULL;
+	}
+	if (m_NeighborXP != NULL)
+	{
+		m_NeighborXP->m_NeighborXM = NULL;
+	}
+	if (m_NeighborZM != NULL)
+	{
+		m_NeighborZM->m_NeighborZP = NULL;
+	}
+	if (m_NeighborZP != NULL)
+	{
+		m_NeighborZP->m_NeighborZM = NULL;
+	}
 }
 
 
@@ -772,9 +812,11 @@ bool cChunk::UnboundedRelGetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE
 {
 	if ((a_RelY < 0) || (a_RelY > cChunkDef::Height))
 	{
+		LOGWARNING("UnboundedRelGetBlock(): requesting a block with a_RelY out of range: %d", a_RelY);
 		return false;
 	}
 	
+	// Is it in this chunk?
 	if ((a_RelX >= 0) && (a_RelX < cChunkDef::Width) && (a_RelZ >= 0) && (a_RelZ < cChunkDef::Width))
 	{
 		int BlockIdx = cChunkDef::MakeIndexNoCheck(a_RelX, a_RelY, a_RelZ);
@@ -782,6 +824,26 @@ bool cChunk::UnboundedRelGetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE
 		a_BlockMeta = GetMeta(BlockIdx);
 		return true;
 	}
+
+	// Not in this chunk, try walking the neighbors first:
+	if ((a_RelX < 0) && (m_NeighborXM != NULL))
+	{
+		return m_NeighborXM->UnboundedRelGetBlock(a_RelX + cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelX >= cChunkDef::Width) && (m_NeighborXP != NULL))
+	{
+		return m_NeighborXP->UnboundedRelGetBlock(a_RelX - cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ < 0) && (m_NeighborZM != NULL))
+	{
+		return m_NeighborZM->UnboundedRelGetBlock(a_RelX, a_RelY, a_RelZ + cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ >= cChunkDef::Width) && (m_NeighborZP != NULL))
+	{
+		return m_NeighborZP->UnboundedRelGetBlock(a_RelX, a_RelY, a_RelZ - cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+
+	// Neighbors not available, use the chunkmap to locate the chunk:
 	return m_ChunkMap->LockedGetBlock(
 		m_PosX * cChunkDef::Width + a_RelX,
 		ZERO_CHUNK_Y * cChunkDef::Height + a_RelY,
@@ -796,11 +858,38 @@ bool cChunk::UnboundedRelGetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE
 
 bool cChunk::UnboundedRelSetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
 {
+	if ((a_RelY < 0) || (a_RelY > cChunkDef::Height))
+	{
+		LOGWARNING("UnboundedRelSetBlock(): requesting a block with a_RelY out of range: %d", a_RelY);
+		return false;
+	}
+	
+	// Is it in this chunk?
 	if ((a_RelX >= 0) && (a_RelX < cChunkDef::Width) && (a_RelZ >= 0) && (a_RelZ < cChunkDef::Width))
 	{
 		SetBlock(a_RelX, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
 		return true;
 	}
+	
+	// Not in this chunk, try walking the neighbors first:
+	if ((a_RelX < 0) && (m_NeighborXM != NULL))
+	{
+		return m_NeighborXM->UnboundedRelSetBlock(a_RelX + cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelX >= cChunkDef::Width) && (m_NeighborXP != NULL))
+	{
+		return m_NeighborXP->UnboundedRelSetBlock(a_RelX - cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ < 0) && (m_NeighborZM != NULL))
+	{
+		return m_NeighborZM->UnboundedRelSetBlock(a_RelX, a_RelY, a_RelZ + cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ >= cChunkDef::Width) && (m_NeighborZP != NULL))
+	{
+		return m_NeighborZP->UnboundedRelSetBlock(a_RelX, a_RelY, a_RelZ - cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+
+	// Neighbors not available, use the chunkmap to locate the chunk:
 	return m_ChunkMap->LockedSetBlock(
 		m_PosX * cChunkDef::Width + a_RelX,
 		ZERO_CHUNK_Y * cChunkDef::Height + a_RelY,
@@ -815,11 +904,38 @@ bool cChunk::UnboundedRelSetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE
 
 bool cChunk::UnboundedRelFastSetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta)
 {
+	if ((a_RelY < 0) || (a_RelY > cChunkDef::Height))
+	{
+		LOGWARNING("UnboundedRelFastSetBlock(): requesting a block with a_RelY out of range: %d", a_RelY);
+		return false;
+	}
+
+	// Is it in this chunk?	
 	if ((a_RelX >= 0) && (a_RelX < cChunkDef::Width) && (a_RelZ >= 0) && (a_RelZ < cChunkDef::Width))
 	{
 		FastSetBlock(a_RelX, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
 		return true;
 	}
+
+	// Not in this chunk, try walking the neighbors first:
+	if ((a_RelX < 0) && (m_NeighborXM != NULL))
+	{
+		return m_NeighborXM->UnboundedRelFastSetBlock(a_RelX + cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelX >= cChunkDef::Width) && (m_NeighborXP != NULL))
+	{
+		return m_NeighborXP->UnboundedRelFastSetBlock(a_RelX - cChunkDef::Width, a_RelY, a_RelZ, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ < 0) && (m_NeighborZM != NULL))
+	{
+		return m_NeighborZM->UnboundedRelFastSetBlock(a_RelX, a_RelY, a_RelZ + cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+	if ((a_RelZ >= cChunkDef::Width) && (m_NeighborZP != NULL))
+	{
+		return m_NeighborZP->UnboundedRelFastSetBlock(a_RelX, a_RelY, a_RelZ - cChunkDef::Width, a_BlockType, a_BlockMeta);
+	}
+
+	// Neighbors not available, use the chunkmap to locate the chunk:
 	return m_ChunkMap->LockedFastSetBlock(
 		m_PosX * cChunkDef::Width + a_RelX,
 		ZERO_CHUNK_Y * cChunkDef::Height + a_RelY,
diff --git a/source/Chunk.h b/source/Chunk.h
index eaa4f82b8..c285a26e3 100644
--- a/source/Chunk.h
+++ b/source/Chunk.h
@@ -59,7 +59,11 @@ class cChunk :
 	public cChunkDef  // The inheritance is "misused" here only to inherit the functions and constants defined in cChunkDef
 {
 public:
-	cChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ, cChunkMap * a_ChunkMap, cWorld * a_World);
+	cChunk(
+		int a_ChunkX, int a_ChunkY, int a_ChunkZ,   // Chunk coords
+		cChunkMap * a_ChunkMap, cWorld * a_World,   // Parent objects
+		cChunk * a_NeighborXM, cChunk * a_NeighborXP, cChunk * a_NeighborZM, cChunk * a_NeighborZP  // Neighbor chunks
+	);
 	~cChunk();
 
 	bool IsValid(void) const {return m_IsValid; }  // Returns true if the chunk block data is valid (loaded / generated)
@@ -267,6 +271,11 @@ private:
 	cChunkDef::BiomeMap  m_BiomeMap;
 
 	int m_BlockTickX, m_BlockTickY, m_BlockTickZ;
+	
+	cChunk * m_NeighborXM;  // Neighbor at [X - 1, Z]
+	cChunk * m_NeighborXP;  // Neighbor at [X + 1, Z]
+	cChunk * m_NeighborZM;  // Neighbor at [X,     Z - 1]
+	cChunk * m_NeighborZP;  // Neighbor at [X,     Z + 1]
 
 	void RemoveBlockEntity( cBlockEntity* a_BlockEntity );
 	void AddBlockEntity( cBlockEntity* a_BlockEntity );
@@ -303,13 +312,13 @@ private:
 	/// Checks if a leaves block at the specified coords has a log up to 4 blocks away connected by other leaves blocks (false if no log)
 	bool HasNearLog(cBlockArea & a_Area, int a_BlockX, int a_BlockY, int a_BlockZ);
 	
-	/// Same as GetBlock(), but relative coords needn't be in this chunk (uses m_ChunkMap in such a case); returns true on success; only usable in Tick()
+	/// Same as GetBlock(), but relative coords needn't be in this chunk (uses m_Neighbor-s or m_ChunkMap in such a case); returns true on success; only usable in Tick()
 	bool UnboundedRelGetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE & a_BlockType, NIBBLETYPE & a_BlockMeta);
 	
-	/// Same as SetBlock(), but relative coords needn't be in this chunk (uses m_ChunkMap in such a case); returns true on success; only usable in Tick()
+	/// Same as SetBlock(), but relative coords needn't be in this chunk (uses m_Neighbor-s or m_ChunkMap in such a case); returns true on success; only usable in Tick()
 	bool UnboundedRelSetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
 
-	/// Same as FastSetBlock(), but relative coords needn't be in this chunk (uses m_ChunkMap in such a case); returns true on success; only usable in Tick()
+	/// Same as FastSetBlock(), but relative coords needn't be in this chunk (uses m_Neighbor-s or m_ChunkMap in such a case); returns true on success; only usable in Tick()
 	bool UnboundedRelFastSetBlock(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, NIBBLETYPE a_BlockMeta);
 };
 
diff --git a/source/ChunkMap.cpp b/source/ChunkMap.cpp
index 9c93f3e08..61ca51ab0 100644
--- a/source/ChunkMap.cpp
+++ b/source/ChunkMap.cpp
@@ -84,7 +84,38 @@ cChunkMap::cChunkLayer * cChunkMap::GetLayer(int a_LayerX, int a_LayerZ)
 
 
 
-cChunkMap::cChunkLayer * cChunkMap::GetLayerForChunk( int a_ChunkX, int a_ChunkZ )
+cChunkMap::cChunkLayer * cChunkMap::FindLayerForChunk(int a_ChunkX, int a_ChunkZ)
+{
+	const int LayerX = (int)(floorf((float)a_ChunkX / (float)(LAYER_SIZE)));
+	const int LayerZ = (int)(floorf((float)a_ChunkZ / (float)(LAYER_SIZE)));
+	return FindLayer(LayerX, LayerZ);
+}
+
+
+
+
+
+cChunkMap::cChunkLayer * cChunkMap::FindLayer(int a_LayerX, int a_LayerZ)
+{
+	ASSERT(m_CSLayers.IsLockedByCurrentThread());
+
+	for (cChunkLayerList::const_iterator itr = m_Layers.begin(); itr != m_Layers.end(); ++itr)
+	{
+		if (((*itr)->GetX() == a_LayerX) && ((*itr)->GetZ() == a_LayerZ))
+		{
+			return *itr;
+		}
+	}  // for itr - m_Layers[]
+	
+	// Not found
+	return NULL;
+}
+
+
+
+
+
+cChunkMap::cChunkLayer * cChunkMap::GetLayerForChunk(int a_ChunkX, int a_ChunkZ)
 {
 	const int LayerX = (int)(floorf((float)a_ChunkX / (float)(LAYER_SIZE)));
 	const int LayerZ = (int)(floorf((float)a_ChunkZ / (float)(LAYER_SIZE)));
@@ -98,6 +129,8 @@ cChunkMap::cChunkLayer * cChunkMap::GetLayerForChunk( int a_ChunkX, int a_ChunkZ
 cChunkPtr cChunkMap::GetChunk( int a_ChunkX, int a_ChunkY, int a_ChunkZ )
 {
 	// No need to lock m_CSLayers, since it's already locked by the operation that called us
+	ASSERT(m_CSLayers.IsLockedByCurrentThread());
+
 	cChunkLayer * Layer = GetLayerForChunk( a_ChunkX, a_ChunkZ );
 	if (Layer == NULL)
 	{
@@ -224,6 +257,22 @@ bool cChunkMap::LockedFastSetBlock(int a_BlockX, int a_BlockY, int a_BlockZ, BLO
 
 
 
+cChunk * cChunkMap::FindChunk(int a_ChunkX, int a_ChunkZ)
+{
+	ASSERT(m_CSLayers.IsLockedByCurrentThread());
+	
+	cChunkLayer * Layer = FindLayerForChunk(a_ChunkX, a_ChunkZ);
+	if (Layer == NULL)
+	{
+		return NULL;
+	}
+	return Layer->FindChunk(a_ChunkX, a_ChunkZ);
+}
+
+
+
+
+
 void cChunkMap::BroadcastPlayerAnimation(const cPlayer & a_Player, char a_Animation, const cClientHandle * a_Exclude)
 {
 	cCSLock Lock(m_CSLayers);
@@ -1786,8 +1835,31 @@ cChunkPtr cChunkMap::cChunkLayer::GetChunk( int a_ChunkX, int a_ChunkY, int a_Ch
 	int Index = LocalX + LocalZ * LAYER_SIZE;
 	if (m_Chunks[Index] == NULL)
 	{
-		m_Chunks[Index] = new cChunk(a_ChunkX, 0, a_ChunkZ, m_Parent, m_Parent->GetWorld());
+		cChunk * neixm = (LocalX > 0)              ? m_Chunks[Index - 1]          : m_Parent->FindChunk(a_ChunkX - 1, a_ChunkZ);
+		cChunk * neixp = (LocalX < LAYER_SIZE - 1) ? m_Chunks[Index + 1]          : m_Parent->FindChunk(a_ChunkX + 1, a_ChunkZ);
+		cChunk * neizm = (LocalZ > 0)              ? m_Chunks[Index - LAYER_SIZE] : m_Parent->FindChunk(a_ChunkX    , a_ChunkZ - 1);
+		cChunk * neizp = (LocalZ < LAYER_SIZE - 1) ? m_Chunks[Index + LAYER_SIZE] : m_Parent->FindChunk(a_ChunkX    , a_ChunkZ + 1);
+		m_Chunks[Index] = new cChunk(a_ChunkX, 0, a_ChunkZ, m_Parent, m_Parent->GetWorld(), neixm, neixp, neizm, neizp);
+	}
+	return m_Chunks[Index];
+}
+
+
+
+
+
+cChunk * cChunkMap::cChunkLayer::FindChunk(int a_ChunkX, int a_ChunkZ)
+{
+	const int LocalX = a_ChunkX - m_LayerX * LAYER_SIZE;
+	const int LocalZ = a_ChunkZ - m_LayerZ * LAYER_SIZE;
+	
+	if (!((LocalX < LAYER_SIZE) && (LocalZ < LAYER_SIZE) && (LocalX > -1) && (LocalZ > -1)))
+	{
+		ASSERT(!"Asking a cChunkLayer for a chunk that doesn't belong to it!");
+		return NULL;
 	}
+	
+	int Index = LocalX + LocalZ * LAYER_SIZE;
 	return m_Chunks[Index];
 }
 
diff --git a/source/ChunkMap.h b/source/ChunkMap.h
index 38d16d0c4..5dd4778ce 100644
--- a/source/ChunkMap.h
+++ b/source/ChunkMap.h
@@ -264,6 +264,9 @@ private:
 		/// 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; }
 		
@@ -288,12 +291,20 @@ private:
 	};
 	
 	typedef std::list<cChunkLayer *> cChunkLayerList;
-	// TODO: Use smart pointers for cChunkLayerList as well, so that ticking and saving needn't lock the entire layerlist
-	// This however means that cChunkLayer needs to interlock its m_Chunks[]
 
-	cChunkLayer * GetLayerForChunk( int a_ChunkX, int a_ChunkZ );  // Creates the layer if it doesn't already exist
-	cChunkLayer * GetLayer( int a_LayerX, int a_LayerZ );  // Creates the layer if it doesn't already exist
-	void RemoveLayer( cChunkLayer* a_Layer );
+	/// 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;
@@ -313,6 +324,9 @@ private:
 
 	/// 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);
 };