17 files changed, 290 insertions, 98 deletions

diff --git a/src/BlockEntities/ChestEntity.cpp b/src/BlockEntities/ChestEntity.cpp
index dfbe6ae87..cb9cc89bf 100644
--- a/src/BlockEntities/ChestEntity.cpp
+++ b/src/BlockEntities/ChestEntity.cpp
@@ -122,6 +122,13 @@ void cChestEntity::UsedBy(cPlayer * a_Player)
 
 void cChestEntity::OpenNewWindow(void)
 {
+	// TODO: cats are an obstruction
+	if ((GetPosY() + 1 < cChunkDef::Height) && cBlockInfo::IsSolid(GetWorld()->GetBlock(GetPosX(), GetPosY() + 1, GetPosZ())))
+	{
+		// Obstruction, don't open
+		return;
+	}
+
 	// Callback for opening together with neighbor chest:
 	class cOpenDouble :
 		public cChestCallback
@@ -135,6 +142,12 @@ void cChestEntity::OpenNewWindow(void)
 		
 		virtual bool Item(cChestEntity * a_Chest) override
 		{
+			if ((a_Chest->GetPosY() + 1 < cChunkDef::Height) && cBlockInfo::IsSolid(a_Chest->GetWorld()->GetBlock(a_Chest->GetPosX(), a_Chest->GetPosY() + 1, a_Chest->GetPosZ())))
+			{
+				// Obstruction, don't open
+				return false;
+			}
+
 			// The primary chest should eb the one with lesser X or Z coord:
 			cChestEntity * Primary = a_Chest;
 			cChestEntity * Secondary = m_ThisChest;
diff --git a/src/BlockEntities/HopperEntity.cpp b/src/BlockEntities/HopperEntity.cpp
index 7f001c739..5856f20d1 100644
--- a/src/BlockEntities/HopperEntity.cpp
+++ b/src/BlockEntities/HopperEntity.cpp
@@ -294,23 +294,24 @@ bool cHopperEntity::MoveItemsOut(cChunk & a_Chunk, Int64 a_CurrentTick)
 		return false;
 	}
 	
-	int bx, by, bz;
+	// Get the coords of the block where to output items:
+	int OutX, OutY, OutZ;
 	NIBBLETYPE Meta = a_Chunk.GetMeta(m_RelX, m_PosY, m_RelZ);
-	if (!GetOutputBlockPos(Meta, bx, by, bz))
+	if (!GetOutputBlockPos(Meta, OutX, OutY, OutZ))
 	{
 		// Not attached to another container
 		return false;
 	}
-	if (by < 0)
+	if (OutY < 0)
 	{
 		// Cannot output below the zero-th block level
 		return false;
 	}
 	
 	// Convert coords to relative:
-	int rx = bx - a_Chunk.GetPosX() * cChunkDef::Width;
-	int rz = bz - a_Chunk.GetPosZ() * cChunkDef::Width;
-	cChunk * DestChunk = a_Chunk.GetRelNeighborChunkAdjustCoords(rx, rz);
+	int OutRelX = OutX - a_Chunk.GetPosX() * cChunkDef::Width;
+	int OutRelZ = OutZ - a_Chunk.GetPosZ() * cChunkDef::Width;
+	cChunk * DestChunk = a_Chunk.GetRelNeighborChunkAdjustCoords(OutRelX, OutRelZ);
 	if (DestChunk == NULL)
 	{
 		// The destination chunk has been unloaded, don't tick
@@ -319,26 +320,32 @@ bool cHopperEntity::MoveItemsOut(cChunk & a_Chunk, Int64 a_CurrentTick)
 	
 	// Call proper moving function, based on the blocktype present at the coords:
 	bool res = false;
-	switch (DestChunk->GetBlock(rx, by, rz))
+	switch (DestChunk->GetBlock(OutRelX, OutY, OutRelZ))
 	{
 		case E_BLOCK_CHEST:
 		{
 			// Chests have special handling because of double-chests
-			res = MoveItemsToChest(*DestChunk, bx, by, bz);
+			res = MoveItemsToChest(*DestChunk, OutX, OutY, OutZ);
 			break;
 		}
 		case E_BLOCK_LIT_FURNACE:
 		case E_BLOCK_FURNACE:
 		{
 			// Furnaces have special handling because of the direction-to-slot relation
-			res = MoveItemsToFurnace(*DestChunk, bx, by, bz, Meta);
+			res = MoveItemsToFurnace(*DestChunk, OutX, OutY, OutZ, Meta);
 			break;
 		}
 		case E_BLOCK_DISPENSER:
 		case E_BLOCK_DROPPER:
 		case E_BLOCK_HOPPER:
 		{
-			res = MoveItemsToGrid(*(cBlockEntityWithItems *)DestChunk->GetBlockEntity(bx, by, bz));
+			cBlockEntityWithItems * BlockEntity = (cBlockEntityWithItems *)DestChunk->GetBlockEntity(OutX, OutY, OutZ);
+			if (BlockEntity == NULL)
+			{
+				LOGWARNING("%s: A block entity was not found where expected at {%d, %d, %d}", __FUNCTION__, OutX, OutY, OutZ);
+				return false;
+			}
+			res = MoveItemsToGrid(*BlockEntity);
 			break;
 		}
 	}
@@ -359,7 +366,13 @@ bool cHopperEntity::MoveItemsOut(cChunk & a_Chunk, Int64 a_CurrentTick)
 /// Moves items from a chest (dblchest) above the hopper into this hopper. Returns true if contents have changed.
 bool cHopperEntity::MoveItemsFromChest(cChunk & a_Chunk)
 {
-	if (MoveItemsFromGrid(*(cChestEntity *)a_Chunk.GetBlockEntity(m_PosX, m_PosY + 1, m_PosZ)))
+	cChestEntity * Chest = (cChestEntity *)a_Chunk.GetBlockEntity(m_PosX, m_PosY + 1, m_PosZ);
+	if (Chest == NULL)
+	{
+		LOGWARNING("%s: A chest entity was not found where expected, at {%d, %d, %d}", __FUNCTION__, m_PosX, m_PosY + 1, m_PosZ);
+		return false;
+	}
+	if (MoveItemsFromGrid(*Chest))
 	{
 		// Moved the item from the chest directly above the hopper
 		return true;
@@ -389,9 +402,17 @@ bool cHopperEntity::MoveItemsFromChest(cChunk & a_Chunk)
 		{
 			continue;
 		}
-		if (MoveItemsFromGrid(*(cChestEntity *)Neighbor->GetBlockEntity(x, m_PosY, z)))
+		Chest = (cChestEntity *)Neighbor->GetBlockEntity(m_PosX + Coords[i].x, m_PosY + 1, m_PosZ + Coords[i].z);
+		if (Chest == NULL)
 		{
-			return true;
+			LOGWARNING("%s: A chest entity was not found where expected, at {%d, %d, %d}", __FUNCTION__, m_PosX + Coords[i].x, m_PosY + 1, m_PosZ + Coords[i].z);
+		}
+		else
+		{
+			if (MoveItemsFromGrid(*Chest))
+			{
+				return true;
+			}
 		}
 		return false;
 	}
@@ -408,7 +429,11 @@ bool cHopperEntity::MoveItemsFromChest(cChunk & a_Chunk)
 bool cHopperEntity::MoveItemsFromFurnace(cChunk & a_Chunk)
 {
 	cFurnaceEntity * Furnace = (cFurnaceEntity *)a_Chunk.GetBlockEntity(m_PosX, m_PosY + 1, m_PosZ);
-	ASSERT(Furnace != NULL);
+	if (Furnace == NULL)
+	{
+		LOGWARNING("%s: A furnace entity was not found where expected, at {%d, %d, %d}", __FUNCTION__, m_PosX, m_PosY + 1, m_PosZ);
+		return false;
+	}
 	
 	// Try move from the output slot:
 	if (MoveItemsFromSlot(*Furnace, cFurnaceEntity::fsOutput, true))
@@ -517,7 +542,13 @@ bool cHopperEntity::MoveItemsFromSlot(cBlockEntityWithItems & a_Entity, int a_Sl
 bool cHopperEntity::MoveItemsToChest(cChunk & a_Chunk, int a_BlockX, int a_BlockY, int a_BlockZ)
 {
 	// Try the chest directly connected to the hopper:
-	if (MoveItemsToGrid(*(cChestEntity *)a_Chunk.GetBlockEntity(a_BlockX, a_BlockY, a_BlockZ)))
+	cChestEntity * Chest = (cChestEntity *)a_Chunk.GetBlockEntity(a_BlockX, a_BlockY, a_BlockZ);
+	if (Chest == NULL)
+	{
+		LOGWARNING("%s: A chest entity was not found where expected, at {%d, %d, %d}", __FUNCTION__, a_BlockX, a_BlockY, a_BlockZ);
+		return false;
+	}
+	if (MoveItemsToGrid(*Chest))
 	{
 		return true;
 	}
@@ -534,19 +565,27 @@ bool cHopperEntity::MoveItemsToChest(cChunk & a_Chunk, int a_BlockX, int a_Block
 		{0, 1},
 		{0, -1},
 	} ;
+	int RelX = a_BlockX - a_Chunk.GetPosX() * cChunkDef::Width;
+	int RelZ = a_BlockZ - a_Chunk.GetPosZ() * cChunkDef::Width;
 	for (size_t i = 0; i < ARRAYCOUNT(Coords); i++)
 	{
-		int x = m_RelX + Coords[i].x;
-		int z = m_RelZ + Coords[i].z;
+		int x = RelX + Coords[i].x;
+		int z = RelZ + Coords[i].z;
 		cChunk * Neighbor = a_Chunk.GetRelNeighborChunkAdjustCoords(x, z);
 		if (
 			(Neighbor == NULL) ||
-			(Neighbor->GetBlock(x, m_PosY + 1, z) != E_BLOCK_CHEST)
+			(Neighbor->GetBlock(x, a_BlockY, z) != E_BLOCK_CHEST)
 		)
 		{
 			continue;
 		}
-		if (MoveItemsToGrid(*(cChestEntity *)Neighbor->GetBlockEntity(a_BlockX, a_BlockY, a_BlockZ)))
+		Chest = (cChestEntity *)Neighbor->GetBlockEntity(a_BlockX + Coords[i].x, a_BlockY, a_BlockZ + Coords[i].z);
+		if (Chest == NULL)
+		{
+			LOGWARNING("%s: A chest entity was not found where expected, at {%d, %d, %d} (%d, %d)", __FUNCTION__, a_BlockX + Coords[i].x, a_BlockY, a_BlockZ + Coords[i].z, x, z);
+			continue;
+		}
+		if (MoveItemsToGrid(*Chest))
 		{
 			return true;
 		}
diff --git a/src/BlockInfo.cpp b/src/BlockInfo.cpp
index 32fdec905..b084d0915 100644
--- a/src/BlockInfo.cpp
+++ b/src/BlockInfo.cpp
@@ -9,6 +9,7 @@
 
 
 cBlockInfo cBlockInfo::ms_Info[256];
+static bool g_IsBlockInfoInitialized = false;
 
 
 
@@ -43,6 +44,11 @@ cBlockInfo::~cBlockInfo()
 
 cBlockInfo & cBlockInfo::Get(BLOCKTYPE a_Type)
 {
+	if (!g_IsBlockInfoInitialized)
+	{
+		cBlockInfo::Initialize();
+		g_IsBlockInfoInitialized = true;
+	}
 	return ms_Info[a_Type];
 }
 
@@ -448,18 +454,3 @@ void cBlockInfo::Initialize(void)
 
 
 
-
-// This is actually just some code that needs to run at program startup, so it is wrapped into a global var's constructor:
-class cBlockInfoInitializer
-{
-public:
-	cBlockInfoInitializer(void)
-	{
-		cBlockInfo::Initialize();
-	}
-} BlockInfoInitializer;
-
-
-
-
-
diff --git a/src/Blocks/BlockDoor.cpp b/src/Blocks/BlockDoor.cpp
index fb2d6f2dc..934a01994 100644
--- a/src/Blocks/BlockDoor.cpp
+++ b/src/Blocks/BlockDoor.cpp
@@ -45,9 +45,16 @@ void cBlockDoorHandler::OnDestroyed(cChunkInterface & a_ChunkInterface, cWorldIn
 
 void cBlockDoorHandler::OnUse(cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface, cPlayer * a_Player, int a_BlockX, int a_BlockY, int a_BlockZ, eBlockFace a_BlockFace, int a_CursorX, int a_CursorY, int a_CursorZ)
 {
+	UNUSED(a_WorldInterface);
+	UNUSED(a_BlockFace);
+	UNUSED(a_CursorX);
+	UNUSED(a_CursorY);
+	UNUSED(a_CursorZ);
+
 	if (a_ChunkInterface.GetBlock(a_BlockX, a_BlockY, a_BlockZ) == E_BLOCK_WOODEN_DOOR)
 	{
 		ChangeDoor(a_ChunkInterface, a_BlockX, a_BlockY, a_BlockZ);
+		a_Player->GetWorld()->BroadcastSoundParticleEffect(1003, a_BlockX, a_BlockY, a_BlockZ, 0, a_Player->GetClientHandle());
 	}
 }
 
diff --git a/src/Blocks/BlockFenceGate.h b/src/Blocks/BlockFenceGate.h
index e202c6610..e992870d4 100644
--- a/src/Blocks/BlockFenceGate.h
+++ b/src/Blocks/BlockFenceGate.h
@@ -45,6 +45,7 @@ public:
 			// Standing aside - use last direction
 			a_ChunkInterface.SetBlockMeta(a_BlockX, a_BlockY, a_BlockZ, OldMetaData);
 		}
+		a_Player->GetWorld()->BroadcastSoundParticleEffect(1003, a_BlockX, a_BlockY, a_BlockZ, 0, a_Player->GetClientHandle());
 	}
 
 
diff --git a/src/Blocks/BlockHandler.cpp b/src/Blocks/BlockHandler.cpp
index a7b89fcb7..405c9bf43 100644
--- a/src/Blocks/BlockHandler.cpp
+++ b/src/Blocks/BlockHandler.cpp
@@ -85,6 +85,91 @@
 
 
 
+/*
+// Tests the meta rotation and mirroring.
+// Note that the cMetaRotator needs to have its assert paths disabled for this test to work!
+static class cBlockHandlerRotationTester
+{
+public:
+	cBlockHandlerRotationTester(void)
+	{
+		printf("Performing block handlers test...\n");
+		for (BLOCKTYPE Type = 0; Type < E_BLOCK_MAX_TYPE_ID; Type++)
+		{
+			cBlockHandler * Handler = cBlockInfo::GetHandler(Type);
+			if (Handler == NULL)
+			{
+				printf("NULL handler for block type %d!\n", Type);
+				continue;
+			}
+			AString BlockName = ItemTypeToString(Type);
+			for (NIBBLETYPE Meta = 0; Meta < 16; Meta++)
+			{
+				// Test the CW / CCW rotations:
+				NIBBLETYPE TestMeta;
+				TestMeta = Handler->MetaRotateCW(Handler->MetaRotateCW(Handler->MetaRotateCW(Handler->MetaRotateCW(Meta))));
+				if (TestMeta != Meta)
+				{
+					// 4 CW rotations should produce no change in the meta
+					printf("Handler for blocktype %d (%s) fails CW 4-rotation test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				TestMeta = Handler->MetaRotateCCW(Handler->MetaRotateCCW(Handler->MetaRotateCCW(Handler->MetaRotateCCW(Meta))));
+				if (TestMeta != Meta)
+				{
+					// 4 CCW rotations should produce no change in the meta
+					printf("Handler for blocktype %d (%s) fails CCW 4-rotation test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				TestMeta = Handler->MetaRotateCCW(Handler->MetaRotateCW(Meta));
+				if (TestMeta != Meta)
+				{
+					// CCW rotation of a CW rotation should produce no change in the meta
+					printf("Handler for blocktype %d (%s) fails CCW(CW) rotation test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				TestMeta = Handler->MetaRotateCW(Handler->MetaRotateCCW(Meta));
+				if (TestMeta != Meta)
+				{
+					// CW rotation of a CCW rotation should produce no change in the meta
+					printf("Handler for blocktype %d (%s) fails CW(CCW) rotation test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				
+				// Test the mirroring:
+				TestMeta = Handler->MetaMirrorXY(Handler->MetaMirrorXY(Meta));
+				if (TestMeta != Meta)
+				{
+					// Double-mirroring should produce the same meta:
+					printf("Handler for blocktype %d (%s) fails XY mirror test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				TestMeta = Handler->MetaMirrorXZ(Handler->MetaMirrorXZ(Meta));
+				if (TestMeta != Meta)
+				{
+					// Double-mirroring should produce the same meta:
+					printf("Handler for blocktype %d (%s) fails XZ mirror test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				TestMeta = Handler->MetaMirrorYZ(Handler->MetaMirrorYZ(Meta));
+				if (TestMeta != Meta)
+				{
+					// Double-mirroring should produce the same meta:
+					printf("Handler for blocktype %d (%s) fails YZ mirror test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+				
+				// Test mirror-rotating:
+				TestMeta = Handler->MetaRotateCW(Handler->MetaRotateCW(Handler->MetaMirrorXY(Handler->MetaMirrorYZ(Meta))));
+				if (TestMeta != Meta)
+				{
+					// 2 CW rotations should be the same as XY, YZ mirroring:
+					printf("Handler for blocktype %d (%s) fails rotation-mirror test for meta %d: got back %d\n", Type, BlockName.c_str(), Meta, TestMeta);
+				}
+			}
+		}  // for Type
+		printf("Block handlers test complete.\n");
+	}
+} g_BlockHandlerRotationTester;
+//*/
+
+
+
+
+
 cBlockHandler * cBlockHandler::CreateBlockHandler(BLOCKTYPE a_BlockType)
 {
 	switch(a_BlockType)
@@ -175,7 +260,7 @@ cBlockHandler * cBlockHandler::CreateBlockHandler(BLOCKTYPE a_BlockType)
 		case E_BLOCK_QUARTZ_BLOCK:          return new cBlockQuartzHandler          (a_BlockType);
 		case E_BLOCK_QUARTZ_STAIRS:         return new cBlockStairsHandler          (a_BlockType);
 		case E_BLOCK_RAIL:                  return new cBlockRailHandler            (a_BlockType);
-		case E_BLOCK_REDSTONE_LAMP_ON:      return new cBlockRedstoneLampHandler    (a_BlockType); // We need this to change pickups to an off lamp; else 1.7+ clients crash
+		case E_BLOCK_REDSTONE_LAMP_ON:      return new cBlockRedstoneLampHandler    (a_BlockType);
 		case E_BLOCK_REDSTONE_ORE:          return new cBlockOreHandler             (a_BlockType);
 		case E_BLOCK_REDSTONE_ORE_GLOWING:  return new cBlockOreHandler             (a_BlockType);
 		case E_BLOCK_REDSTONE_REPEATER_OFF: return new cBlockRedstoneRepeaterHandler(a_BlockType);
@@ -207,7 +292,7 @@ cBlockHandler * cBlockHandler::CreateBlockHandler(BLOCKTYPE a_BlockType)
 		case E_BLOCK_TRAPDOOR:              return new cBlockTrapdoorHandler        (a_BlockType);
 		case E_BLOCK_TNT:                   return new cBlockTNTHandler             (a_BlockType);
 		case E_BLOCK_VINES:                 return new cBlockVineHandler            (a_BlockType);
-		case E_BLOCK_WALLSIGN:              return new cBlockSignHandler            (a_BlockType);
+		case E_BLOCK_WALLSIGN:              return new cBlockSignHandler            (a_BlockType);  // TODO: This needs a special handler
 		case E_BLOCK_WATER:                 return new cBlockFluidHandler           (a_BlockType);
 		case E_BLOCK_WOODEN_BUTTON:         return new cBlockButtonHandler          (a_BlockType);
 		case E_BLOCK_WOODEN_DOOR:           return new cBlockDoorHandler            (a_BlockType);
diff --git a/src/Blocks/BlockLever.h b/src/Blocks/BlockLever.h
index ad2ae29e5..f1d3ff6d2 100644
--- a/src/Blocks/BlockLever.h
+++ b/src/Blocks/BlockLever.h
@@ -7,12 +7,13 @@
 
 
 class cBlockLeverHandler :
-	public cMetaRotator<cBlockHandler, 0x07, 0x04, 0x02, 0x03, 0x01, false>
+	public cMetaRotator<cBlockHandler, 0x07, 0x04, 0x01, 0x03, 0x02, false>
 {
-	typedef cMetaRotator<cBlockHandler, 0x07, 0x04, 0x02, 0x03, 0x01, false> super;
+	typedef cMetaRotator<cBlockHandler, 0x07, 0x04, 0x01, 0x03, 0x02, false> super;
+	
 public:
-	cBlockLeverHandler(BLOCKTYPE a_BlockType)
-		: cMetaRotator<cBlockHandler, 0x07, 0x04, 0x02, 0x03, 0x01, false>(a_BlockType)
+	cBlockLeverHandler(BLOCKTYPE a_BlockType) :
+		super(a_BlockType)
 	{
 	}
 	
@@ -132,7 +133,7 @@ public:
 			case 0x05: return 0x06;  // Ground rotation
 			case 0x06: return 0x05;
 
-			default:  return super::MetaRotateCCW(a_Meta);  // Wall Rotation
+			default:  return super::MetaRotateCW(a_Meta);  // Wall Rotation
 		}
 	}
 } ;
diff --git a/src/Blocks/BlockSign.h b/src/Blocks/BlockSign.h
index 9d6fede21..f5630bdb0 100644
--- a/src/Blocks/BlockSign.h
+++ b/src/Blocks/BlockSign.h
@@ -75,13 +75,13 @@ public:
 
 	virtual NIBBLETYPE MetaRotateCW(NIBBLETYPE a_Meta) override
 	{
-		return (++a_Meta) & 0x0F;
+		return (a_Meta + 4) & 0x0f;
 	}
 
 
 	virtual NIBBLETYPE MetaRotateCCW(NIBBLETYPE a_Meta) override
 	{
-		return (--a_Meta) & 0x0F;
+		return (a_Meta + 12) & 0x0f;
 	}
 
 	virtual NIBBLETYPE MetaMirrorXY(NIBBLETYPE a_Meta) override
@@ -90,7 +90,7 @@ public:
 
 		//  There are 16 meta values which correspond to different directions.
 		//  These values are equated to angles on a circle; 0x08 = 180 degrees.
-		return (a_Meta < 0x08) ? 0x08 + a_Meta : 0x08 - a_Meta;
+		return (a_Meta < 0x08) ? (0x08 + a_Meta) : (0x08 - a_Meta);
 	}
 
 
diff --git a/src/Blocks/BlockSlab.h b/src/Blocks/BlockSlab.h
index f3f2366fd..6c861be86 100644
--- a/src/Blocks/BlockSlab.h
+++ b/src/Blocks/BlockSlab.h
@@ -124,6 +124,12 @@ public:
 		return E_BLOCK_AIR;
 	}
 	
+	
+	virtual NIBBLETYPE MetaMirrorXZ(NIBBLETYPE a_Meta) override
+	{
+		// Toggle the 4th bit - up / down:
+		return (a_Meta ^ 0x08);
+	}
 } ;
 
 
@@ -167,15 +173,6 @@ public:
 		ASSERT(!"Unhandled double slab type!");
 		return "";
 	}
-
-
-	virtual NIBBLETYPE MetaMirrorXZ(NIBBLETYPE a_Meta) override
-	{
-		NIBBLETYPE OtherMeta = a_Meta & 0x07;  // Contains unrelated meta data.
-
-		// 8th bit is up/down.  1 right-side-up, 0 is up-side-down.
-		return (a_Meta & 0x08) ? 0x00 + OtherMeta : 0x01 + OtherMeta;
-	}
 } ;
 
 
diff --git a/src/Chunk.cpp b/src/Chunk.cpp
index 0b8e2d1a9..2e14cf368 100644
--- a/src/Chunk.cpp
+++ b/src/Chunk.cpp
@@ -1616,6 +1616,12 @@ void cChunk::AddBlockEntity(cBlockEntity * a_BlockEntity)
 
 cBlockEntity * cChunk::GetBlockEntity(int a_BlockX, int a_BlockY, int a_BlockZ)
 {
+	// Check that the query coords are within chunk bounds:
+	ASSERT(a_BlockX >= m_PosX * cChunkDef::Width);
+	ASSERT(a_BlockX < m_PosX * cChunkDef::Width + cChunkDef::Width);
+	ASSERT(a_BlockZ >= m_PosZ * cChunkDef::Width);
+	ASSERT(a_BlockZ < m_PosZ * cChunkDef::Width + cChunkDef::Width);
+
 	for (cBlockEntityList::iterator itr = m_BlockEntities.begin(); itr != m_BlockEntities.end(); ++itr)
 	{
 		if (
diff --git a/src/ClientHandle.cpp b/src/ClientHandle.cpp
index 1c6c989c5..a39a87077 100644
--- a/src/ClientHandle.cpp
+++ b/src/ClientHandle.cpp
@@ -231,6 +231,9 @@ AString cClientHandle::FormatMessageType(bool ShouldAppendChatPrefixes, eMessage
 
 AString cClientHandle::GenerateOfflineUUID(const AString & a_Username)
 {
+	// Online UUIDs are always version 4 (random)
+	// We use Version 3 (MD5 hash) UUIDs for the offline UUIDs
+	// This guarantees that they will never collide with an online UUID and can be distinguished.
 	// Proper format for a version 3 UUID is:
 	// xxxxxxxx-xxxx-3xxx-yxxx-xxxxxxxxxxxx where x is any hexadecimal digit and y is one of 8, 9, A, or B
 	
@@ -253,6 +256,32 @@ AString cClientHandle::GenerateOfflineUUID(const AString & a_Username)
 
 
 
+bool cClientHandle::IsUUIDOnline(const AString & a_UUID)
+{
+	// Online UUIDs are always version 4 (random)
+	// We use Version 3 (MD5 hash) UUIDs for the offline UUIDs
+	// This guarantees that they will never collide with an online UUID and can be distinguished.
+	// The version-specifying char is at pos #12 of raw UUID, pos #14 in dashed-UUID.
+	switch (a_UUID.size())
+	{
+		case 32:
+		{
+			// This is the UUID format without dashes, the version char is at pos #12:
+			return (a_UUID[12] == '4');
+		}
+		case 36:
+		{
+			// This is the UUID format with dashes, the version char is at pos #14:
+			return (a_UUID[14] == '4');
+		}
+	}
+	return false;
+}
+
+
+
+
+
 void cClientHandle::Kick(const AString & a_Reason)
 {
 	if (m_State >= csAuthenticating)  // Don't log pings
diff --git a/src/ClientHandle.h b/src/ClientHandle.h
index 99d10c3aa..d6e086bd2 100644
--- a/src/ClientHandle.h
+++ b/src/ClientHandle.h
@@ -63,7 +63,7 @@ public:
 
 	const AString & GetIPString(void) const { return m_IPString; }
 	
-	cPlayer* GetPlayer() { return m_Player; }	// tolua_export
+	cPlayer * GetPlayer(void) { return m_Player; }	// tolua_export
 
 	const AString & GetUUID(void) const { return m_UUID; } // tolua_export
 	void SetUUID(const AString & a_UUID) { m_UUID = a_UUID; }
@@ -76,9 +76,16 @@ public:
 	
 	/** Generates an UUID based on the player name provided.
 	This is used for the offline (non-auth) mode, when there's no UUID source.
-	Each username generates a unique and constant UUID, so that when the player reconnects with the same name, their UUID is the same. */
+	Each username generates a unique and constant UUID, so that when the player reconnects with the same name, their UUID is the same.
+	Returns a 36-char UUID (with dashes). */
 	static AString GenerateOfflineUUID(const AString & a_Username);  // tolua_export
 	
+	/** Returns true if the UUID is generated by online auth, false if it is an offline-generated UUID.
+	We use Version-3 UUIDs for offline UUIDs, online UUIDs are Version-4, thus we can tell them apart.
+	Accepts both 32-char and 36-char UUIDs (with and without dashes).
+	If the string given is not a valid UUID, returns false. */
+	static bool IsUUIDOnline(const AString & a_UUID);  // tolua_export
+	
 	/** Formats the type of message with the proper color and prefix for sending to the client. **/
 	static AString FormatMessageType(bool ShouldAppendChatPrefixes, eMessageType a_ChatPrefix, const AString & a_AdditionalData);
 	
diff --git a/src/Generating/Prefab.cpp b/src/Generating/Prefab.cpp
index 2ab1455b9..7d876909a 100644
--- a/src/Generating/Prefab.cpp
+++ b/src/Generating/Prefab.cpp
@@ -211,6 +211,17 @@ void cPrefab::Draw(cChunkDesc & a_Dest, const Vector3i & a_Placement, int a_NumR
 	int ChunkStartZ = a_Dest.GetChunkZ() * cChunkDef::Width;
 	Placement.Move(-ChunkStartX, 0, -ChunkStartZ);
 	const cBlockArea & Image = m_BlockArea[a_NumRotations];
+	
+	// If the placement is outside this chunk, bail out:
+	if (
+		(Placement.x > cChunkDef::Width) || (Placement.x + Image.GetSizeX() < 0) ||
+		(Placement.z > cChunkDef::Width) || (Placement.z + Image.GetSizeZ() < 0)
+	)
+	{
+		return;
+	}
+	
+	// Write the image:
 	a_Dest.WriteBlockArea(Image, Placement.x, Placement.y, Placement.z, m_MergeStrategy);
 	
 	// If requested, draw the floor (from the bottom of the prefab down to the nearest non-air)
diff --git a/src/Simulator/IncrementalRedstoneSimulator.cpp b/src/Simulator/IncrementalRedstoneSimulator.cpp
index 183c527ca..10446a879 100644
--- a/src/Simulator/IncrementalRedstoneSimulator.cpp
+++ b/src/Simulator/IncrementalRedstoneSimulator.cpp
@@ -59,21 +59,20 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 	int RelZ = 0;	
 	BLOCKTYPE Block;
 	NIBBLETYPE Meta;
-	cChunk * Chunk;
+	cChunk * OtherChunk = a_Chunk;
 
 	if (a_OtherChunk != NULL)
 	{
 		RelX = a_BlockX - a_OtherChunk->GetPosX() * cChunkDef::Width;
 		RelZ = a_BlockZ - a_OtherChunk->GetPosZ() * cChunkDef::Width;
 		a_OtherChunk->GetBlockTypeMeta(RelX, a_BlockY, RelZ, Block, Meta);
-		Chunk = a_OtherChunk;
+		OtherChunk = a_OtherChunk;
 	}
 	else
 	{
 		RelX = a_BlockX - a_Chunk->GetPosX() * cChunkDef::Width;
 		RelZ = a_BlockZ - a_Chunk->GetPosZ() * cChunkDef::Width;
 		a_Chunk->GetBlockTypeMeta(RelX, a_BlockY, RelZ, Block, Meta);
-		Chunk = a_Chunk;
 	}
 
 	// Every time a block is changed (AddBlock called), we want to go through all lists and check to see if the coordiantes stored within are still valid
@@ -92,7 +91,8 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 		{
 			LOGD("cIncrementalRedstoneSimulator: Erased block @ {%i, %i, %i} from powered blocks list as it no longer connected to a source", itr->a_BlockPos.x, itr->a_BlockPos.y, itr->a_BlockPos.z);
 			itr = PoweredBlocks->erase(itr);
-			Chunk->SetIsRedstoneDirty(true);
+			a_Chunk->SetIsRedstoneDirty(true);
+			OtherChunk->SetIsRedstoneDirty(true);
 			continue;
 		}
 		else if (
@@ -107,21 +107,23 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 		{
 			LOGD("cIncrementalRedstoneSimulator: Erased block @ {%i, %i, %i} from powered blocks list due to present/past metadata mismatch", itr->a_BlockPos.x, itr->a_BlockPos.y, itr->a_BlockPos.z);
 			itr = PoweredBlocks->erase(itr);
-			Chunk->SetIsRedstoneDirty(true);
+			a_Chunk->SetIsRedstoneDirty(true);
+			OtherChunk->SetIsRedstoneDirty(true);
 			continue;
 		}
 		else if (Block == E_BLOCK_DAYLIGHT_SENSOR)
 		{
-			if (!m_World.IsChunkLighted(Chunk->GetPosX(), Chunk->GetPosZ()))
+			if (!m_World.IsChunkLighted(OtherChunk->GetPosX(), OtherChunk->GetPosZ()))
 			{
-				m_World.QueueLightChunk(Chunk->GetPosX(), Chunk->GetPosZ());
+				m_World.QueueLightChunk(OtherChunk->GetPosX(), OtherChunk->GetPosZ());
 			}
 			else
 			{
-				if (Chunk->GetTimeAlteredLight(Chunk->GetSkyLight(RelX, a_BlockY + 1, RelZ)) <= 7)
+				if (OtherChunk->GetTimeAlteredLight(OtherChunk->GetSkyLight(RelX, a_BlockY + 1, RelZ)) <= 7)
 				{
 					itr = PoweredBlocks->erase(itr);
-					Chunk->SetIsRedstoneDirty(true);
+					a_Chunk->SetIsRedstoneDirty(true);
+					OtherChunk->SetIsRedstoneDirty(true);
 					continue;
 				}
 			}
@@ -139,7 +141,8 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 			{
 				LOGD("cIncrementalRedstoneSimulator: Erased block @ {%i, %i, %i} from linked powered blocks list as it is no longer connected to a source", itr->a_BlockPos.x, itr->a_BlockPos.y, itr->a_BlockPos.z);
 				itr = LinkedPoweredBlocks->erase(itr);
-				Chunk->SetIsRedstoneDirty(true);
+				a_Chunk->SetIsRedstoneDirty(true);
+				OtherChunk->SetIsRedstoneDirty(true);
 				continue;
 			}
 			else if (
@@ -153,7 +156,8 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 			{
 				LOGD("cIncrementalRedstoneSimulator: Erased block @ {%i, %i, %i} from linked powered blocks list due to present/past metadata mismatch", itr->a_BlockPos.x, itr->a_BlockPos.y, itr->a_BlockPos.z);
 				itr = LinkedPoweredBlocks->erase(itr);
-				Chunk->SetIsRedstoneDirty(true);
+				a_Chunk->SetIsRedstoneDirty(true);
+				OtherChunk->SetIsRedstoneDirty(true);
 				continue;
 			}
 		}
@@ -163,7 +167,8 @@ void cIncrementalRedstoneSimulator::RedstoneAddBlock(int a_BlockX, int a_BlockY,
 			{
 				LOGD("cIncrementalRedstoneSimulator: Erased block @ {%i, %i, %i} from linked powered blocks list as it is no longer powered through a valid middle block", itr->a_BlockPos.x, itr->a_BlockPos.y, itr->a_BlockPos.z);
 				itr = LinkedPoweredBlocks->erase(itr);
-				Chunk->SetIsRedstoneDirty(true);
+				a_Chunk->SetIsRedstoneDirty(true);
+				OtherChunk->SetIsRedstoneDirty(true);
 				continue;
 			}
 		}
@@ -343,6 +348,7 @@ void cIncrementalRedstoneSimulator::SimulateChunk(float a_Dt, int a_ChunkX, int
 				case E_BLOCK_REDSTONE_REPEATER_ON:
 				{
 					HandleRedstoneRepeater(dataitr->x, dataitr->y, dataitr->z, dataitr->Data);
+					break;
 				}
 				case E_BLOCK_REDSTONE_TORCH_OFF:
 				case E_BLOCK_REDSTONE_TORCH_ON:
@@ -520,8 +526,11 @@ void cIncrementalRedstoneSimulator::HandleFenceGate(int a_RelBlockX, int a_RelBl
 	{
 		if (!AreCoordsSimulated(a_RelBlockX, a_RelBlockY, a_RelBlockZ, true))
 		{
-			m_Chunk->SetMeta(a_RelBlockX, a_RelBlockY, a_RelBlockZ, MetaData | 0x4);
-			m_Chunk->BroadcastSoundParticleEffect(1003, BlockX, a_RelBlockY, BlockZ, 0);
+			if ((MetaData & 0x4) == 0)
+			{
+				m_Chunk->SetMeta(a_RelBlockX, a_RelBlockY, a_RelBlockZ, MetaData | 0x4);
+				m_Chunk->BroadcastSoundParticleEffect(1003, BlockX, a_RelBlockY, BlockZ, 0);
+			}
 			SetPlayerToggleableBlockAsSimulated(a_RelBlockX, a_RelBlockY, a_RelBlockZ, true);
 		}
 	}
@@ -529,8 +538,11 @@ void cIncrementalRedstoneSimulator::HandleFenceGate(int a_RelBlockX, int a_RelBl
 	{
 		if (!AreCoordsSimulated(a_RelBlockX, a_RelBlockY, a_RelBlockZ, false))
 		{
-			m_Chunk->SetMeta(a_RelBlockX, a_RelBlockY, a_RelBlockZ, MetaData & 0xFFFFFFFB);
-			m_Chunk->BroadcastSoundParticleEffect(1003, BlockX, a_RelBlockY, BlockZ, 0);
+			if ((MetaData & 0x4) != 0)
+			{
+				m_Chunk->SetMeta(a_RelBlockX, a_RelBlockY, a_RelBlockZ, MetaData & ~0x04);
+				m_Chunk->BroadcastSoundParticleEffect(1003, BlockX, a_RelBlockY, BlockZ, 0);
+			}
 			SetPlayerToggleableBlockAsSimulated(a_RelBlockX, a_RelBlockY, a_RelBlockZ, false);
 		}
 	}
@@ -758,7 +770,7 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeater(int a_RelBlockX, int
 
 void cIncrementalRedstoneSimulator::HandleRedstoneRepeaterDelays()
 {
-	for (RepeatersDelayList::iterator itr = m_RepeatersDelayList->begin(); itr != m_RepeatersDelayList->end(); itr++)
+	for (RepeatersDelayList::iterator itr = m_RepeatersDelayList->begin(); itr != m_RepeatersDelayList->end();)
 	{
 
 		if (itr->a_ElapsedTicks >= itr->a_DelayTicks) // Has the elapsed ticks reached the target ticks?
@@ -804,7 +816,7 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeaterDelays()
 			{
 				m_Chunk->SetBlock(RelBlockX, RelBlockY, RelBlockZ, E_BLOCK_REDSTONE_REPEATER_OFF, Meta);
 			}
-			m_RepeatersDelayList->erase(itr);
+			itr = m_RepeatersDelayList->erase(itr);
 		}
 		else
 		{
@@ -813,6 +825,7 @@ void cIncrementalRedstoneSimulator::HandleRedstoneRepeaterDelays()
 			// I am confounded to say why. Perhaps optimisation failure.
 			LOGD("Incremented a repeater @ {%i %i %i} | Elapsed ticks: %i | Target delay: %i", itr->a_RelBlockPos.x, itr->a_RelBlockPos.y, itr->a_RelBlockPos.z, itr->a_ElapsedTicks, itr->a_DelayTicks);
 			itr->a_ElapsedTicks++;
+			itr++;
 		}
 	}
 }
@@ -1072,19 +1085,17 @@ void cIncrementalRedstoneSimulator::HandleNoteBlock(int a_RelBlockX, int a_RelBl
 
 void cIncrementalRedstoneSimulator::HandleDaylightSensor(int a_RelBlockX, int a_RelBlockY, int a_RelBlockZ)
 {
-	int a_ChunkX, a_ChunkZ;
-	cChunkDef::BlockToChunk(a_RelBlockX, a_RelBlockZ, a_ChunkX, a_ChunkZ);
+	int BlockX = (m_Chunk->GetPosX() * cChunkDef::Width) + a_RelBlockX, BlockZ = (m_Chunk->GetPosZ() * cChunkDef::Width) + a_RelBlockZ;
+	int ChunkX, ChunkZ;
+	cChunkDef::BlockToChunk(BlockX, BlockZ, ChunkX, ChunkZ);
 
-	if (!m_World.IsChunkLighted(a_ChunkX, a_ChunkZ))
+	if (!m_World.IsChunkLighted(ChunkX, ChunkZ))
 	{
-		m_World.QueueLightChunk(a_ChunkX, a_ChunkZ);
+		m_World.QueueLightChunk(ChunkX, ChunkZ);
 	}
 	else
 	{
-		int BlockX = (m_Chunk->GetPosX() * cChunkDef::Width) + a_RelBlockX;
-		int BlockZ = (m_Chunk->GetPosZ() * cChunkDef::Width) + a_RelBlockZ;
-		NIBBLETYPE SkyLight = m_Chunk->GetTimeAlteredLight(m_World.GetBlockSkyLight(BlockX, a_RelBlockY + 1, BlockZ));
-		if (SkyLight > 8)
+		if (m_Chunk->GetTimeAlteredLight(m_World.GetBlockSkyLight(BlockX, a_RelBlockY + 1, BlockZ)) > 8)
 		{
 			SetAllDirsAsPowered(a_RelBlockX, a_RelBlockY, a_RelBlockZ);
 		}
diff --git a/src/VoronoiMap.cpp b/src/VoronoiMap.cpp
index 9c3ca7e65..5efd09c01 100644
--- a/src/VoronoiMap.cpp
+++ b/src/VoronoiMap.cpp
@@ -14,7 +14,9 @@ cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
 	m_Noise1(a_Seed + 1),
 	m_Noise2(a_Seed + 2),
 	m_Noise3(a_Seed + 3),
-	m_CellSize(a_CellSize)
+	m_CellSize(a_CellSize),
+	m_CurrentCellX(9999999),  // Cell coords that are definitely out of the range for normal generator, so that the first query will overwrite them
+	m_CurrentCellZ(9999999)
 {
 }
 
diff --git a/src/WorldStorage/NBTChunkSerializer.cpp b/src/WorldStorage/NBTChunkSerializer.cpp
index d058a4583..93ade6448 100644
--- a/src/WorldStorage/NBTChunkSerializer.cpp
+++ b/src/WorldStorage/NBTChunkSerializer.cpp
@@ -345,6 +345,7 @@ void cNBTChunkSerializer::AddBasicEntity(cEntity * a_Entity, const AString & a_C
 		m_Writer.AddDouble("", a_Entity->GetYaw());
 		m_Writer.AddDouble("", a_Entity->GetPitch());
 	m_Writer.EndList();
+	m_Writer.AddShort("Health", a_Entity->GetHealth());
 }
 
 
@@ -576,7 +577,6 @@ void cNBTChunkSerializer::AddPickupEntity(cPickup * a_Pickup)
 	m_Writer.BeginCompound("");
 		AddBasicEntity(a_Pickup, "Item");
 		AddItem(a_Pickup->GetItem(), -1, "Item");
-		m_Writer.AddShort("Health", (Int16)(unsigned char)a_Pickup->GetHealth());
 		m_Writer.AddShort("Age",    (Int16)a_Pickup->GetAge());
 	m_Writer.EndCompound();
 }
@@ -679,7 +679,6 @@ void cNBTChunkSerializer::AddExpOrbEntity(cExpOrb * a_ExpOrb)
 {
 	m_Writer.BeginCompound("");
 		AddBasicEntity(a_ExpOrb, "XPOrb");
-		m_Writer.AddShort("Health", (Int16)(unsigned char)a_ExpOrb->GetHealth());
 		m_Writer.AddShort("Age", (Int16)a_ExpOrb->GetAge());
 		m_Writer.AddShort("Value", (Int16)a_ExpOrb->GetReward());
 	m_Writer.EndCompound();
diff --git a/src/WorldStorage/WSSAnvil.cpp b/src/WorldStorage/WSSAnvil.cpp
index a3259b769..f714c0414 100644
--- a/src/WorldStorage/WSSAnvil.cpp
+++ b/src/WorldStorage/WSSAnvil.cpp
@@ -1461,13 +1461,6 @@ void cWSSAnvil::LoadPickupFromNBT(cEntityList & a_Entities, const cParsedNBT & a
 	{
 		return;
 	}
-
-	// Load health:
-	int Health = a_NBT.FindChildByName(a_TagIdx, "Health");
-	if (Health > 0)
-	{
-		Pickup->SetHealth((int) (a_NBT.GetShort(Health) & 0xFF));
-	}
 	
 	// Load age:
 	int Age = a_NBT.FindChildByName(a_TagIdx, "Age");
@@ -1513,13 +1506,6 @@ void cWSSAnvil::LoadExpOrbFromNBT(cEntityList & a_Entities, const cParsedNBT & a
 		return;
 	}
 
-	// Load Health:
-	int Health = a_NBT.FindChildByName(a_TagIdx, "Health");
-	if (Health > 0)
-	{
-		ExpOrb->SetHealth((int) (a_NBT.GetShort(Health) & 0xFF));
-	}
-
 	// Load Age:
 	int Age = a_NBT.FindChildByName(a_TagIdx, "Age");
 	if (Age > 0)
@@ -2437,6 +2423,13 @@ bool cWSSAnvil::LoadEntityBaseFromNBT(cEntity & a_Entity, const cParsedNBT & a_N
 	}
 	a_Entity.SetYaw(Rotation[0]);
 	a_Entity.SetRoll(Rotation[1]);
+
+	// Load health:
+	int Health = a_NBT.FindChildByName(a_TagIdx, "Health");
+	if (Health > 0)
+	{
+		a_Entity.SetHealth(a_NBT.GetShort(Health));
+	}
 	
 	return true;
 }