17 files changed, 339 insertions, 111 deletions

diff --git a/src/Blocks/BlockHandler.cpp b/src/Blocks/BlockHandler.cpp
index cee2f4b99..30b303cfd 100644
--- a/src/Blocks/BlockHandler.cpp
+++ b/src/Blocks/BlockHandler.cpp
@@ -427,7 +427,7 @@ void cBlockHandler::DropBlock(cChunkInterface & a_ChunkInterface, cWorldInterfac
 	if (a_CanDrop)
 	{
 		if ((a_Digger != NULL) && (a_Digger->GetEquippedWeapon().m_Enchantments.GetLevel(cEnchantments::enchSilkTouch) > 0))
-		{				
+		{
 			switch (m_BlockType)
 			{
 				case E_BLOCK_CAKE:
diff --git a/src/ClientHandle.cpp b/src/ClientHandle.cpp
index 487ef3867..43a4161e4 100644
--- a/src/ClientHandle.cpp
+++ b/src/ClientHandle.cpp
@@ -312,8 +312,16 @@ void cClientHandle::Authenticate(const AString & a_Name, const AString & a_UUID,
 	ASSERT(m_Player == NULL);
 
 	m_Username = a_Name;
-	m_UUID = a_UUID;
-	m_Properties = a_Properties;
+	
+	// Only assign UUID and properties if not already pre-assigned (BungeeCord sends those in the Handshake packet):
+	if (m_UUID.empty())
+	{
+		m_UUID = a_UUID;
+	}
+	if (m_Properties.empty())
+	{
+		m_Properties = a_Properties;
+	}
 	
 	// Send login success (if the protocol supports it):
 	m_Protocol->SendLoginSuccess();
diff --git a/src/ClientHandle.h b/src/ClientHandle.h
index 05d05e052..b91c3722c 100644
--- a/src/ClientHandle.h
+++ b/src/ClientHandle.h
@@ -64,15 +64,27 @@ public:
 
 	const AString & GetIPString(void) const { return m_IPString; }  // tolua_export
 	
+	/** Sets the IP string that the client is using. Overrides the IP string that was read from the socket.
+	Used mainly by BungeeCord compatibility code. */
+	void SetIPString(const AString & a_IPString) { m_IPString = a_IPString; }
+	
 	cPlayer * GetPlayer(void) { return m_Player; }  // tolua_export
 
 	/** Returns the player's UUID, as used by the protocol, in the short form (no dashes) */
 	const AString & GetUUID(void) const { return m_UUID; }  // tolua_export
 	
-	void SetUUID(const AString & a_UUID) { m_UUID = a_UUID; }
+	/** Sets the player's UUID, as used by the protocol. Short UUID form (no dashes) is expected.
+	Used mainly by BungeeCord compatibility code - when authenticating is done on the BungeeCord server
+	and the results are passed to MCS running in offline mode. */
+	void SetUUID(const AString & a_UUID) { ASSERT(a_UUID.size() == 32); m_UUID = a_UUID; }
 
 	const Json::Value & GetProperties(void) const { return m_Properties; }
 	
+	/** Sets the player's properties, such as skin image and signature.
+	Used mainly by BungeeCord compatibility code - property querying is done on the BungeeCord server
+	and the results are passed to MCS running in offline mode. */
+	void SetProperties(const Json::Value & a_Properties) { m_Properties = a_Properties; }
+	
 	/** Generates an UUID based on the username stored for this client, and stores it in the m_UUID member.
 	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.
diff --git a/src/Defines.h b/src/Defines.h
index 78c58034e..6355b75b4 100644
--- a/src/Defines.h
+++ b/src/Defines.h
@@ -115,12 +115,14 @@ enum eGameMode
 	eGameMode_Survival  = 0,
 	eGameMode_Creative  = 1,
 	eGameMode_Adventure = 2,
+	eGameMode_Spectator = 3,
 	
 	// Easier-to-use synonyms:
 	gmNotSet    = eGameMode_NotSet,
 	gmSurvival  = eGameMode_Survival,
 	gmCreative  = eGameMode_Creative,
 	gmAdventure = eGameMode_Adventure,
+	gmSpectator = eGameMode_Spectator,
 	
 	// These two are used to check GameMode for validity when converting from integers.
 	gmMax,  // Gets automatically assigned
diff --git a/src/Entities/Player.cpp b/src/Entities/Player.cpp
index 55065d550..871311e86 100644
--- a/src/Entities/Player.cpp
+++ b/src/Entities/Player.cpp
@@ -451,6 +451,11 @@ void cPlayer::CancelChargingBow(void)
 
 void cPlayer::SetTouchGround(bool a_bTouchGround)
 {
+	if (IsGameModeSpectator())  // You can fly through the ground in Spectator
+	{
+		return;
+	}
+	
 	m_bTouchGround = a_bTouchGround;
 
 	if (!m_bTouchGround)
@@ -585,7 +590,7 @@ bool cPlayer::Feed(int a_Food, double a_Saturation)
 
 void cPlayer::AddFoodExhaustion(double a_Exhaustion)
 {
-	if (!IsGameModeCreative())
+	if (!(IsGameModeCreative() || IsGameModeSpectator()))
 	{
 		m_FoodExhaustionLevel = std::min(m_FoodExhaustionLevel + a_Exhaustion, 40.0);
 	}
@@ -823,9 +828,9 @@ bool cPlayer::DoTakeDamage(TakeDamageInfo & a_TDI)
 {
 	if ((a_TDI.DamageType != dtInVoid) && (a_TDI.DamageType != dtPlugin))
 	{
-		if (IsGameModeCreative())
+		if (IsGameModeCreative() || IsGameModeSpectator())
 		{
-			// No damage / health in creative mode if not void or plugin damage
+			// No damage / health in creative or spectator mode if not void or plugin damage
 			return false;
 		}
 	}
@@ -1043,6 +1048,14 @@ bool cPlayer::IsGameModeAdventure(void) const
 
 
 
+bool cPlayer::IsGameModeSpectator(void) const
+{
+	return (m_GameMode == gmSpectator) ||  // Either the player is explicitly in Spectator
+		((m_GameMode == gmNotSet) &&  m_World->IsGameModeSpectator());  // or they inherit from the world and the world is Adventure
+}
+
+
+
 
 void cPlayer::SetTeam(cTeam * a_Team)
 {
@@ -1158,7 +1171,7 @@ void cPlayer::SetGameMode(eGameMode a_GameMode)
 	m_GameMode = a_GameMode;
 	m_ClientHandle->SendGameMode(a_GameMode);
 
-	if (!IsGameModeCreative())
+	if (!(IsGameModeCreative() || IsGameModeSpectator()))
 	{
 		SetFlying(false);
 		SetCanFly(false);
@@ -1342,6 +1355,7 @@ void cPlayer::MoveTo( const Vector3d & a_NewPos)
 
 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
 	{
 		m_bVisible = true;
@@ -1502,6 +1516,11 @@ void cPlayer::TossPickup(const cItem & a_Item)
 
 void cPlayer::TossItems(const cItems & a_Items)
 {
+	if (IsGameModeSpectator())  // Players can't toss items in spectator
+	{
+		return;
+	}
+	
 	m_Stats.AddValue(statItemsDropped, (StatValue)a_Items.Size());
 
 	double vX = 0, vY = 0, vZ = 0;
@@ -1788,7 +1807,7 @@ bool cPlayer::SaveToDisk()
 
 void cPlayer::UseEquippedItem(int a_Amount)
 {
-	if (IsGameModeCreative())  // No damage in creative
+	if (IsGameModeCreative() || IsGameModeSpectator())  // No damage in creative or spectator
 	{
 		return;
 	}
diff --git a/src/Entities/Player.h b/src/Entities/Player.h
index 9821cc6d9..d64dd6b99 100644
--- a/src/Entities/Player.h
+++ b/src/Entities/Player.h
@@ -171,6 +171,9 @@ public:
 	/** Returns true if the player is in Adventure mode, either explicitly, or by inheriting from current world */
 	bool IsGameModeAdventure(void) const;
 	
+	/** Returns true if the player is in Spectator mode, either explicitly, or by inheriting from current world */
+	bool IsGameModeSpectator(void) const;
+	
 	AString GetIP(void) const { return m_IP; }  // tolua_export
 
 	/** Returns the associated team, NULL if none */
diff --git a/src/Generating/BioGen.cpp b/src/Generating/BioGen.cpp
index 60ad4e3eb..217ca8f80 100644
--- a/src/Generating/BioGen.cpp
+++ b/src/Generating/BioGen.cpp
@@ -13,72 +13,6 @@
 
 
 ////////////////////////////////////////////////////////////////////////////////
-// cBiomeGen:
-
-cBiomeGen * cBiomeGen::CreateBiomeGen(cIniFile & a_IniFile, int a_Seed, bool & a_CacheOffByDefault)
-{
-	AString BiomeGenName = a_IniFile.GetValueSet("Generator", "BiomeGen", "");
-	if (BiomeGenName.empty())
-	{
-		LOGWARN("[Generator] BiomeGen value not set in world.ini, using \"MultiStepMap\".");
-		BiomeGenName = "MultiStepMap";
-	}
-	
-	cBiomeGen * res = NULL;
-	a_CacheOffByDefault = false;
-	if (NoCaseCompare(BiomeGenName, "constant") == 0)
-	{
-		res = new cBioGenConstant;
-		a_CacheOffByDefault = true;  // we're generating faster than a cache would retrieve data :)
-	}
-	else if (NoCaseCompare(BiomeGenName, "checkerboard") == 0)
-	{
-		res = new cBioGenCheckerboard;
-		a_CacheOffByDefault = true;  // we're (probably) generating faster than a cache would retrieve data
-	}
-	else if (NoCaseCompare(BiomeGenName, "voronoi") == 0)
-	{
-		res = new cBioGenVoronoi(a_Seed);
-	}
-	else if (NoCaseCompare(BiomeGenName, "distortedvoronoi") == 0)
-	{
-		res = new cBioGenDistortedVoronoi(a_Seed);
-	}
-	else if (NoCaseCompare(BiomeGenName, "twolevel") == 0)
-	{
-		res = new cBioGenTwoLevel(a_Seed);
-	}
-	else
-	{
-		if (NoCaseCompare(BiomeGenName, "multistepmap") != 0)
-		{
-			LOGWARNING("Unknown BiomeGen \"%s\", using \"MultiStepMap\" instead.", BiomeGenName.c_str());
-		}
-		res = new cBioGenMultiStepMap(a_Seed);
-
-		/*
-		// Performance-testing:
-		LOGINFO("Measuring performance of cBioGenMultiStepMap...");
-		clock_t BeginTick = clock();
-		for (int x = 0; x < 5000; x++)
-		{
-			cChunkDef::BiomeMap Biomes;
-			res->GenBiomes(x * 5, x * 5, Biomes);
-		}
-		clock_t Duration = clock() - BeginTick;
-		LOGINFO("cBioGenMultiStepMap for 5000 chunks took %d ticks (%.02f sec)", Duration, (double)Duration / CLOCKS_PER_SEC);
-		//*/
-	}
-	res->InitializeBiomeGen(a_IniFile);
-	
-	return res;
-}
-
-
-
-
-
-////////////////////////////////////////////////////////////////////////////////
 // cBioGenConstant:
 
 void cBioGenConstant::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
@@ -402,8 +336,13 @@ void cBioGenVoronoi::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap &
 void cBioGenVoronoi::InitializeBiomeGen(cIniFile & a_IniFile)
 {
 	super::InitializeBiomeGen(a_IniFile);
-	m_Voronoi.SetCellSize(a_IniFile.GetValueSetI("Generator", "VoronoiCellSize", 64));
-	InitializeBiomes     (a_IniFile.GetValueSet ("Generator", "VoronoiBiomes",   ""));
+	int CellSize     = a_IniFile.GetValueSetI("Generator", "VoronoiCellSize", 128);
+	int JitterSize   = a_IniFile.GetValueSetI("Generator", "VoronoiJitterSize", CellSize);
+	int OddRowOffset = a_IniFile.GetValueSetI("Generator", "VoronoiOddRowOffset", 0);
+	m_Voronoi.SetCellSize(CellSize);
+	m_Voronoi.SetJitterSize(JitterSize);
+	m_Voronoi.SetOddRowOffset(OddRowOffset);
+	InitializeBiomes(a_IniFile.GetValueSet ("Generator", "VoronoiBiomes",   ""));
 }
 
 
@@ -846,9 +785,10 @@ void cBioGenTwoLevel::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap
 	{
 		for (int x = 0; x < cChunkDef::Width; x++)
 		{
-			int MinDist1, MinDist2;
-			int BiomeGroup = m_VoronoiLarge.GetValueAt(DistortX[x][z], DistortZ[x][z], MinDist1, MinDist2) / 7;
-			int BiomeIdx   = m_VoronoiSmall.GetValueAt(DistortX[x][z], DistortZ[x][z], MinDist1, MinDist2) / 11;
+			int SeedX, SeedZ, MinDist2;
+			int BiomeGroup = m_VoronoiLarge.GetValueAt(DistortX[x][z], DistortZ[x][z], SeedX, SeedZ, MinDist2) / 7;
+			int BiomeIdx   = m_VoronoiSmall.GetValueAt(DistortX[x][z], DistortZ[x][z], SeedX, SeedZ, MinDist2) / 11;
+			int MinDist1 = (DistortX[x][z] - SeedX) * (DistortX[x][z] - SeedX) + (DistortZ[x][z] - SeedZ) * (DistortZ[x][z] - SeedZ);
 			cChunkDef::SetBiome(a_BiomeMap, x, z, SelectBiome(BiomeGroup, BiomeIdx, (MinDist1 < MinDist2 / 4) ? 0 : 1));
 		}
 	}
@@ -987,3 +927,69 @@ void cBioGenTwoLevel::InitializeBiomeGen(cIniFile & a_IniFile)
 
 
 
+
+////////////////////////////////////////////////////////////////////////////////
+// cBiomeGen:
+
+cBiomeGen * cBiomeGen::CreateBiomeGen(cIniFile & a_IniFile, int a_Seed, bool & a_CacheOffByDefault)
+{
+	AString BiomeGenName = a_IniFile.GetValueSet("Generator", "BiomeGen", "");
+	if (BiomeGenName.empty())
+	{
+		LOGWARN("[Generator] BiomeGen value not set in world.ini, using \"MultiStepMap\".");
+		BiomeGenName = "MultiStepMap";
+	}
+
+	cBiomeGen * res = NULL;
+	a_CacheOffByDefault = false;
+	if (NoCaseCompare(BiomeGenName, "constant") == 0)
+	{
+		res = new cBioGenConstant;
+		a_CacheOffByDefault = true;  // we're generating faster than a cache would retrieve data :)
+	}
+	else if (NoCaseCompare(BiomeGenName, "checkerboard") == 0)
+	{
+		res = new cBioGenCheckerboard;
+		a_CacheOffByDefault = true;  // we're (probably) generating faster than a cache would retrieve data
+	}
+	else if (NoCaseCompare(BiomeGenName, "voronoi") == 0)
+	{
+		res = new cBioGenVoronoi(a_Seed);
+	}
+	else if (NoCaseCompare(BiomeGenName, "distortedvoronoi") == 0)
+	{
+		res = new cBioGenDistortedVoronoi(a_Seed);
+	}
+	else if (NoCaseCompare(BiomeGenName, "twolevel") == 0)
+	{
+		res = new cBioGenTwoLevel(a_Seed);
+	}
+	else
+	{
+		if (NoCaseCompare(BiomeGenName, "multistepmap") != 0)
+		{
+			LOGWARNING("Unknown BiomeGen \"%s\", using \"MultiStepMap\" instead.", BiomeGenName.c_str());
+		}
+		res = new cBioGenMultiStepMap(a_Seed);
+
+		/*
+		// Performance-testing:
+		LOGINFO("Measuring performance of cBioGenMultiStepMap...");
+		clock_t BeginTick = clock();
+		for (int x = 0; x < 5000; x++)
+		{
+			cChunkDef::BiomeMap Biomes;
+			res->GenBiomes(x * 5, x * 5, Biomes);
+		}
+		clock_t Duration = clock() - BeginTick;
+		LOGINFO("cBioGenMultiStepMap for 5000 chunks took %d ticks (%.02f sec)", Duration, (double)Duration / CLOCKS_PER_SEC);
+		//*/
+	}
+	res->InitializeBiomeGen(a_IniFile);
+
+	return res;
+}
+
+
+
+
diff --git a/src/Protocol/Protocol17x.cpp b/src/Protocol/Protocol17x.cpp
index 05935fbe1..2fbc58541 100644
--- a/src/Protocol/Protocol17x.cpp
+++ b/src/Protocol/Protocol17x.cpp
@@ -102,6 +102,19 @@ cProtocol172::cProtocol172(cClientHandle * a_Client, const AString & a_ServerAdd
 	m_IsEncrypted(false),
 	m_LastSentDimension(dimNotSet)
 {
+	// BungeeCord handling:
+	// If BC is setup with ip_forward == true, it sends additional data in the login packet's ServerAddress field:
+	// hostname\00ip-address\00uuid\00profile-properties-as-json
+	AStringVector Params;
+	if (cRoot::Get()->GetServer()->ShouldAllowBungeeCord() && SplitZeroTerminatedStrings(a_ServerAddress, Params) && (Params.size() == 4))
+	{
+		LOGD("Player at %s connected via BungeeCord", Params[1].c_str());
+		m_ServerAddress = Params[0];
+		m_Client->SetIPString(Params[1]);
+		m_Client->SetUUID(cMojangAPI::MakeUUIDShort(Params[2]));
+		m_Client->SetProperties(Params[3]);
+	}
+	
 	// Create the comm log file, if so requested:
 	if (g_ShouldLogCommIn || g_ShouldLogCommOut)
 	{
diff --git a/src/Protocol/ProtocolRecognizer.cpp b/src/Protocol/ProtocolRecognizer.cpp
index 36e791fc7..4516975bf 100644
--- a/src/Protocol/ProtocolRecognizer.cpp
+++ b/src/Protocol/ProtocolRecognizer.cpp
@@ -28,7 +28,7 @@
 cProtocolRecognizer::cProtocolRecognizer(cClientHandle * a_Client) :
 	super(a_Client),
 	m_Protocol(NULL),
-	m_Buffer(512)
+	m_Buffer(8192)     // We need a larger buffer to support BungeeCord - it sends one huge packet at the start
 {
 }
 
diff --git a/src/Root.cpp b/src/Root.cpp
index 86a497a76..966a9b4ba 100644
--- a/src/Root.cpp
+++ b/src/Root.cpp
@@ -113,8 +113,8 @@ void cRoot::Start(void)
 	LOG("--- Started Log ---\n");
 
 	#ifdef BUILD_ID
-	LOG("MCServer " BUILD_SERIES_NAME " build id: " BUILD_ID );
-	LOG("from commit id: " BUILD_COMMIT_ID " built at: " BUILD_DATETIME );
+	LOG("MCServer " BUILD_SERIES_NAME " build id: " BUILD_ID);
+	LOG("from commit id: " BUILD_COMMIT_ID " built at: " BUILD_DATETIME);
 	#endif
 
 	cDeadlockDetect dd;
diff --git a/src/Server.cpp b/src/Server.cpp
index 069e2a169..969ffd693 100644
--- a/src/Server.cpp
+++ b/src/Server.cpp
@@ -259,6 +259,13 @@ bool cServer::InitServer(cIniFile & a_SettingsIni)
 		m_ServerID = sid.str();
 		m_ServerID.resize(16, '0');
 	}
+
+	// Check if both BungeeCord and online mode are on, if so, warn the admin:
+	m_ShouldAllowBungeeCord = a_SettingsIni.GetValueSetB("Authentication", "AllowBungeeCord", false);
+	if (m_ShouldAllowBungeeCord && m_ShouldAuthenticate)
+	{
+		LOGWARNING("WARNING: BungeeCord is allowed and server set to online mode. This is unsafe and will not work properly. Disable either authentication or BungeeCord in settings.ini.");
+	}
 	
 	m_ShouldLoadOfflinePlayerData = a_SettingsIni.GetValueSetB("PlayerData", "LoadOfflinePlayerData", false);
 	m_ShouldLoadNamedPlayerData   = a_SettingsIni.GetValueSetB("PlayerData", "LoadNamedPlayerData", true);
diff --git a/src/Server.h b/src/Server.h
index f20e6932f..6d659fa40 100644
--- a/src/Server.h
+++ b/src/Server.h
@@ -131,6 +131,11 @@ public:  // tolua_export
 	Loaded from the settings.ini [PlayerData].LoadNamedPlayerData setting. */
 	bool ShouldLoadNamedPlayerData(void) const { return m_ShouldLoadNamedPlayerData; }
 	
+	/** Returns true if BungeeCord logins (that specify the player's UUID) are allowed.
+	Read from settings, admins should set this to true only when they chain to BungeeCord,
+	it makes the server vulnerable to identity theft through direct connections. */
+	bool ShouldAllowBungeeCord(void) const { return m_ShouldAllowBungeeCord; }
+	
 private:
 
 	friend class cRoot;  // so cRoot can create and destroy cServer
@@ -230,6 +235,9 @@ private:
 	This allows a seamless transition from name-based to UUID-based player storage.
 	Loaded from the settings.ini [PlayerData].LoadNamedPlayerData setting. */
 	bool m_ShouldLoadNamedPlayerData;
+	
+	/** True if BungeeCord handshake packets (with player UUID) should be accepted. */
+	bool m_ShouldAllowBungeeCord;
 
 
 	cServer(void);
diff --git a/src/StringUtils.cpp b/src/StringUtils.cpp
index 5f88cbf64..73147eebc 100644
--- a/src/StringUtils.cpp
+++ b/src/StringUtils.cpp
@@ -869,3 +869,31 @@ void SetBEInt(char * a_Mem, Int32 a_Value)
 
 
 
+
+bool SplitZeroTerminatedStrings(const AString & a_Strings, AStringVector & a_Output)
+{
+	a_Output.clear();
+	size_t size = a_Strings.size();
+	size_t start = 0;
+	bool res = false;
+	for (size_t i = 0; i < size; i++)
+	{
+		if (a_Strings[i] == 0)
+		{
+			a_Output.push_back(a_Strings.substr(start, i - start));
+			start = i + 1;
+			res = true;
+		}
+	}
+	if (start < size)
+	{
+		a_Output.push_back(a_Strings.substr(start, size - start));
+		res = true;
+	}
+	
+	return res;
+}
+
+
+
+
diff --git a/src/StringUtils.h b/src/StringUtils.h
index 72a90a8c2..a76894d05 100644
--- a/src/StringUtils.h
+++ b/src/StringUtils.h
@@ -99,6 +99,11 @@ extern int GetBEInt(const char * a_Mem);
 /// Writes four bytes to the specified memory location so that they interpret as BigEndian int
 extern void SetBEInt(char * a_Mem, Int32 a_Value);
 
+/** Splits a string that has embedded \0 characters, on those characters.
+a_Output is first cleared and then each separate string is pushed back into a_Output.
+Returns true if there are at least two strings in a_Output (there was at least one \0 separator). */
+extern bool SplitZeroTerminatedStrings(const AString & a_Strings, AStringVector & a_Output);
+
 /// Parses any integer type. Checks bounds and returns errors out of band.
 template <class T>
 bool StringToInteger(const AString & a_str, T & a_Num)
diff --git a/src/VoronoiMap.cpp b/src/VoronoiMap.cpp
index 5efd09c01..5ad634fe4 100644
--- a/src/VoronoiMap.cpp
+++ b/src/VoronoiMap.cpp
@@ -10,11 +10,13 @@
 
 
 
-cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
+cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize, int a_JitterSize) :
 	m_Noise1(a_Seed + 1),
 	m_Noise2(a_Seed + 2),
 	m_Noise3(a_Seed + 3),
-	m_CellSize(a_CellSize),
+	m_CellSize(std::max(a_CellSize, 2)),
+	m_JitterSize(Clamp(a_JitterSize, 1, a_CellSize)),
+	m_OddRowOffset(0),
 	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)
 {
@@ -26,7 +28,29 @@ cVoronoiMap::cVoronoiMap(int a_Seed, int a_CellSize) :
 
 void cVoronoiMap::SetCellSize(int a_CellSize)
 {
+	a_CellSize = std::max(a_CellSize, 2);  // Cell size must be at least 2
 	m_CellSize = a_CellSize;
+
+	// For compatibility with previous version, which didn't have the jitter, we set jitter here as well.
+	m_JitterSize = a_CellSize;
+}
+
+
+
+
+
+void cVoronoiMap::SetJitterSize(int a_JitterSize)
+{
+	m_JitterSize = Clamp(a_JitterSize, 1, m_CellSize);
+}
+
+
+
+
+
+void cVoronoiMap::SetOddRowOffset(int a_OddRowOffset)
+{
+	m_OddRowOffset = Clamp(a_OddRowOffset, -m_CellSize, m_CellSize);
 }
 
 
@@ -35,8 +59,8 @@ void cVoronoiMap::SetCellSize(int a_CellSize)
 
 int cVoronoiMap::GetValueAt(int a_X, int a_Y)
 {
-	int MinDist1, MinDist2;
-	return GetValueAt(a_X, a_Y, MinDist1, MinDist2);
+	int SeedX, SeedY, MinDist2;
+	return GetValueAt(a_X, a_Y, SeedX, SeedY, MinDist2);
 }
 
 
@@ -45,41 +69,47 @@ int cVoronoiMap::GetValueAt(int a_X, int a_Y)
 
 int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist)
 {
-	int MinDist2;
-	return GetValueAt(a_X, a_Y, a_MinDist, MinDist2);
+	int SeedX, SeedY, MinDist2;
+	int res = GetValueAt(a_X, a_Y, SeedX, SeedY, MinDist2);
+	a_MinDist = (a_X - SeedX) * (a_X - SeedX) + (a_Y - SeedY) * (a_Y - SeedY);
+	return res;
 }
 
 
 
 
 
-int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist1, int & a_MinDist2)
+int cVoronoiMap::GetValueAt(
+	int a_X, int a_Y,  // Coords to query
+	int & a_NearestSeedX, int & a_NearestSeedY,  // Coords of the closest cell
+	int & a_MinDist2  // Distance to the second closest cell
+)
 {
-	// Note that due to historical reasons, the algorithm uses XZ coords, while the input uses XY coords.
-	// This is because the algorithm was first implemented directly in the biome generators which use MC coords.
-	
 	int CellX = a_X / m_CellSize;
-	int CellZ = a_Y / m_CellSize;
+	int CellY = a_Y / m_CellSize;
 	
-	UpdateCell(CellX, CellZ);
+	UpdateCell(CellX, CellY);
 	
 	// Get 5x5 neighboring cell seeds, compare distance to each. Return the value in the minumim-distance cell
+	int NearestSeedX = 0, NearestSeedY = 0;
 	int MinDist = m_CellSize * m_CellSize * 16;  // There has to be a cell closer than this
 	int MinDist2 = MinDist;
 	int res = 0;  // Will be overriden
 	for (int x = 0; x < 5; x++)
 	{
-		for (int z = 0; z < 5; z++)
+		for (int y = 0; y < 5; y++)
 		{
-			int SeedX = m_SeedX[x][z];
-			int SeedZ = m_SeedZ[x][z];
+			int SeedX = m_SeedX[x][y];
+			int SeedY = m_SeedZ[x][y];
 			
-			int Dist = (SeedX - a_X) * (SeedX - a_X) + (SeedZ - a_Y) * (SeedZ - a_Y);
+			int Dist = (SeedX - a_X) * (SeedX - a_X) + (SeedY - a_Y) * (SeedY - a_Y);
 			if (Dist < MinDist)
 			{
+				NearestSeedX = SeedX;
+				NearestSeedY = SeedY;
 				MinDist2 = MinDist;
 				MinDist = Dist;
-				res = m_Noise3.IntNoise2DInt(x + CellX - 2, z + CellZ - 2);
+				res = m_Noise3.IntNoise2DInt(x + CellX - 2, y + CellY - 2);
 			}
 			else if (Dist < MinDist2)
 			{
@@ -88,7 +118,8 @@ int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist1, int & a_MinDist2
 		}  // for z
 	}  // for x
 
-	a_MinDist1 = MinDist;
+	a_NearestSeedX = NearestSeedX;
+	a_NearestSeedY = NearestSeedY;
 	a_MinDist2 = MinDist2;
 	return res;
 }
@@ -97,6 +128,58 @@ int cVoronoiMap::GetValueAt(int a_X, int a_Y, int & a_MinDist1, int & a_MinDist2
 
 
 
+void cVoronoiMap::FindNearestSeeds(
+	int a_X, int a_Y,
+	int & a_NearestSeedX, int & a_NearestSeedY,
+	int & a_SecondNearestSeedX, int & a_SecondNearestSeedY
+)
+{
+	int CellX = a_X / m_CellSize;
+	int CellY = a_Y / m_CellSize;
+
+	UpdateCell(CellX, CellY);
+
+	// Get 5x5 neighboring cell seeds, compare distance to each. Return the value in the minumim-distance cell
+	int NearestSeedX = 0, NearestSeedY = 0;
+	int SecondNearestSeedX = 0, SecondNearestSeedY = 0;
+	int MinDist = m_CellSize * m_CellSize * 16;  // There has to be a cell closer than this
+	int MinDist2 = MinDist;
+	for (int x = 0; x < 5; x++)
+	{
+		for (int y = 0; y < 5; y++)
+		{
+			int SeedX = m_SeedX[x][y];
+			int SeedY = m_SeedZ[x][y];
+
+			int Dist = (SeedX - a_X) * (SeedX - a_X) + (SeedY - a_Y) * (SeedY - a_Y);
+			if (Dist < MinDist)
+			{
+				SecondNearestSeedX = NearestSeedX;
+				SecondNearestSeedY = NearestSeedY;
+				MinDist2 = MinDist;
+				NearestSeedX = SeedX;
+				NearestSeedY = SeedY;
+				MinDist = Dist;
+			}
+			else if (Dist < MinDist2)
+			{
+				SecondNearestSeedX = SeedX;
+				SecondNearestSeedY = SeedY;
+				MinDist2 = Dist;
+			}
+		}  // for z
+	}  // for x
+
+	a_NearestSeedX = NearestSeedX;
+	a_NearestSeedY = NearestSeedY;
+	a_SecondNearestSeedX = SecondNearestSeedX;
+	a_SecondNearestSeedY = SecondNearestSeedY;
+}
+
+
+
+
+
 void cVoronoiMap::UpdateCell(int a_CellX, int a_CellZ)
 {
 	// If the specified cell is currently cached, bail out:
@@ -111,12 +194,13 @@ void cVoronoiMap::UpdateCell(int a_CellX, int a_CellZ)
 	for (int x = 0; x < 5; x++)
 	{
 		int BaseX = (NoiseBaseX + x) * m_CellSize;
+		int OddRowOffset = ((NoiseBaseX + x) & 0x01) * m_OddRowOffset;
 		for (int z = 0; z < 5; z++)
 		{
-			int OffsetX = (m_Noise1.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_CellSize;
-			int OffsetZ = (m_Noise2.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_CellSize;
+			int OffsetX = (m_Noise1.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_JitterSize;
+			int OffsetZ = (m_Noise2.IntNoise2DInt(NoiseBaseX + x, NoiseBaseZ + z) / 8) % m_JitterSize;
 			m_SeedX[x][z] = BaseX + OffsetX;
-			m_SeedZ[x][z] = (NoiseBaseZ + z) * m_CellSize + OffsetZ;
+			m_SeedZ[x][z] = (NoiseBaseZ + z) * m_CellSize + OddRowOffset + OffsetZ;
 		}  // for z
 	}  // for x
 	m_CurrentCellX = a_CellX;
diff --git a/src/VoronoiMap.h b/src/VoronoiMap.h
index 84cf206e9..dfb11e9ce 100644
--- a/src/VoronoiMap.h
+++ b/src/VoronoiMap.h
@@ -18,19 +18,40 @@
 class cVoronoiMap
 {
 public:
-	cVoronoiMap(int a_Seed, int a_CellSize = 128);
+	cVoronoiMap(int a_Seed, int a_CellSize = 128, int a_JitterSize = 128);
 	
-	/// Sets the cell size used for generating the Voronoi seeds
+	/** Sets both the cell size and jitter size used for generating the Voronoi seeds. */
 	void SetCellSize(int a_CellSize);
+
+	/** Sets the jitter size. Clamps it to current cell size. */
+	void SetJitterSize(int a_JitterSize);
+
+	/** Sets the offset that is added to each odd row of cells.
+	This offset makes the voronoi cells align to a non-grid.
+	Clamps the value to [-m_CellSize, +m_CellSize]. */
+	void SetOddRowOffset(int a_OddRowOffset);
 	
-	/// Returns the value in the cell into which the specified point lies
+	/** Returns the value in the cell into which the specified point lies. */
 	int GetValueAt(int a_X, int a_Y);
 	
-	/// Returns the value in the cell into which the specified point lies, and the distance to the nearest Voronoi seed
+	/** Returns the value in the cell into which the specified point lies,
+	and the distance to the nearest Voronoi seed. */
 	int GetValueAt(int a_X, int a_Y, int & a_MinDistance);
 	
-	/// Returns the value in the cell into which the specified point lies, and the distances to the 2 nearest Voronoi seeds. Uses a cache
-	int GetValueAt(int a_X, int a_Y, int & a_MinDistance1, int & a_MinDistance2);
+	/** Returns the value in the cell into which the specified point lies,
+	and the distances to the 2 nearest Voronoi seeds. Uses a cache. */
+	int GetValueAt(
+		int a_X, int a_Y,                            // Coords to query
+		int & a_NearestSeedX, int & a_NearestSeedY,  // Coords of the closest cell's seed
+		int & a_MinDist2                             // Distance to the second closest cell's seed
+	);
+
+	/** Finds the nearest and second nearest seeds, returns their coords. */
+	void FindNearestSeeds(
+		int a_X, int a_Y,
+		int & a_NearestSeedX, int & a_NearestSeedY,
+		int & a_SecondNearestSeedX, int & a_SecondNearestSeedY
+	);
 
 protected:
 	/// The noise used for generating Voronoi seeds
@@ -38,8 +59,17 @@ protected:
 	cNoise m_Noise2;
 	cNoise m_Noise3;
 	
-	/// Size of the Voronoi cells (avg X/Y distance between the seeds)
+	/** Size of the Voronoi cells (avg X/Y distance between the seeds). Expected to be at least 2. */
 	int m_CellSize;
+
+	/** The amount that the cell seeds may be offset from the grid.
+	Expected to be at least 1 and less than m_CellSize. */
+	int m_JitterSize;
+
+	/** The constant amount that the cell seeds of every odd row will be offset from the grid.
+	This allows us to have non-rectangular grids.
+	Expected to be between -m_CellSize and +m_CellSize. */
+	int m_OddRowOffset;
 	
 	/** The X coordinate of the currently cached cell neighborhood */
 	int m_CurrentCellX;
diff --git a/src/World.h b/src/World.h
index 391124a03..eee0ced54 100644
--- a/src/World.h
+++ b/src/World.h
@@ -188,6 +188,9 @@ public:
 	/** Returns true if the world is in Adventure mode */
 	bool IsGameModeAdventure(void) const { return (m_GameMode == gmAdventure); }
 	
+	/** Returns true if the world is in Spectator mode */
+	bool IsGameModeSpectator(void) const { return (m_GameMode == gmSpectator); }
+	
 	bool IsPVPEnabled(void) const { return m_bEnabledPVP; }
 	bool IsDeepSnowEnabled(void) const { return m_IsDeepSnowEnabled; }