5 files changed, 144 insertions, 32 deletions

diff --git a/src/Generating/BioGen.cpp b/src/Generating/BioGen.cpp
index 8fad9f5c9..60ad4e3eb 100644
--- a/src/Generating/BioGen.cpp
+++ b/src/Generating/BioGen.cpp
@@ -151,7 +151,7 @@ void cBioGenCache::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a
 		LOGD("BioGenCache: %d hits, %d misses, saved %.2f %%", m_NumHits, m_NumMisses, 100.0 * m_NumHits / (m_NumHits + m_NumMisses));
 		LOGD("BioGenCache: Avg cache chain length: %.2f", (float)m_TotalChain / m_NumHits);
 	}
-	
+
 	for (int i = 0; i < m_CacheSize; i++)
 	{
 		if (
@@ -208,6 +208,59 @@ void cBioGenCache::InitializeBiomeGen(cIniFile & a_IniFile)
 
 
 
+////////////////////////////////////////////////////////////////////////////////
+// cBioGenMulticache:
+
+cBioGenMulticache::cBioGenMulticache(cBiomeGen * a_BioGenToCache, size_t a_CacheSize, size_t a_CachesLength) :
+	m_CachesLength(a_CachesLength)
+{
+	m_Caches.reserve(a_CachesLength);
+	for (size_t i = 0; i < a_CachesLength; i++)
+	{
+		m_Caches.push_back(new cBioGenCache(a_BioGenToCache, a_CacheSize));
+	}
+}
+
+
+
+
+
+cBioGenMulticache::~cBioGenMulticache()
+{
+	for (cBiomeGens::iterator it = m_Caches.begin(); it != m_Caches.end(); it++)
+	{
+		delete *it;
+	}
+}
+
+
+
+
+
+void cBioGenMulticache::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	const size_t coefficient = 3;
+	const size_t cacheIdx = ((size_t)a_ChunkX + coefficient * (size_t)a_ChunkZ) % m_CachesLength;
+
+	m_Caches[cacheIdx]->GenBiomes(a_ChunkX, a_ChunkZ, a_BiomeMap);
+}
+
+
+
+
+
+void cBioGenMulticache::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	for (cBiomeGens::iterator it = m_Caches.begin(); it != m_Caches.end(); it++)
+	{
+		cBiomeGen * tmp = *it;
+		tmp->InitializeBiomeGen(a_IniFile);
+	}
+}
+
+
+
+
 
 ////////////////////////////////////////////////////////////////////////////////
 // cBiomeGenList:
diff --git a/src/Generating/BioGen.h b/src/Generating/BioGen.h
index 227ec97d7..20d199611 100644
--- a/src/Generating/BioGen.h
+++ b/src/Generating/BioGen.h
@@ -80,6 +80,36 @@ protected:
 
 
 
+class cBioGenMulticache :
+	public cBiomeGen
+{
+
+	typedef cBiomeGen super;
+
+public:
+	/*
+	a_CacheSize defines the size of each singular cache
+	a_CachesLength defines how many caches are used for the multicache
+	*/
+	cBioGenMulticache(cBiomeGen * a_BioGenToCache, size_t a_CacheSize, size_t a_CachesLength);  // Doesn't take ownership of a_BioGenToCache
+	~cBioGenMulticache();
+
+protected:
+	typedef std::vector<cBiomeGen *> cBiomeGens;
+
+
+	size_t     m_CachesLength;
+	cBiomeGens m_Caches;
+
+
+	virtual void GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap) override;
+	virtual void InitializeBiomeGen(cIniFile & a_IniFile) override;
+};
+
+
+
+
+
 /// Base class for generators that use a list of available biomes. This class takes care of the list.
 class cBiomeGenList :
 	public cBiomeGen
diff --git a/src/Generating/ChunkGenerator.cpp b/src/Generating/ChunkGenerator.cpp
index a1188f984..d615456c1 100644
--- a/src/Generating/ChunkGenerator.cpp
+++ b/src/Generating/ChunkGenerator.cpp
@@ -52,10 +52,21 @@ bool cChunkGenerator::Start(cPluginInterface & a_PluginInterface, cChunkSink & a
 	m_PluginInterface = &a_PluginInterface;
 	m_ChunkSink = &a_ChunkSink;
 
-	MTRand rnd;
-	m_Seed = a_IniFile.GetValueSetI("Seed", "Seed", (int)rnd.randInt());
+	// Get the seed; create a new one and log it if not found in the INI file:
+	if (a_IniFile.HasValue("Seed", "Seed"))
+	{
+		m_Seed = a_IniFile.GetValueI("Seed", "Seed");
+	}
+	else
+	{
+		MTRand rnd;
+		m_Seed = rnd.randInt();
+		LOGINFO("Chosen a new random seed for world: %d", m_Seed);
+		a_IniFile.SetValueI("Seed", "Seed", m_Seed);
+	}
+	
+	// Get the generator engine based on the INI file settings:
 	AString GeneratorName = a_IniFile.GetValueSet("Generator", "Generator", "Composable");
-
 	if (NoCaseCompare(GeneratorName, "Noise3D") == 0)
 	{
 		m_Generator = new cNoise3DGenerator(*this);
@@ -99,15 +110,17 @@ void cChunkGenerator::Stop(void)
 
 
 
-void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ)
+void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate)
 {
+	ASSERT(m_ChunkSink->IsChunkQueued(a_ChunkX, a_ChunkZ));
+
 	{
 		cCSLock Lock(m_CS);
 
 		// Check if it is already in the queue:
-		for (cChunkCoordsList::iterator itr = m_Queue.begin(); itr != m_Queue.end(); ++itr)
+		for (cChunkCoordsWithBoolList::iterator itr = m_Queue.begin(); itr != m_Queue.end(); ++itr)
 		{
-			if ((itr->m_ChunkX == a_ChunkX) && (itr->m_ChunkY == a_ChunkY) && (itr->m_ChunkZ == a_ChunkZ))
+			if ((itr->m_ChunkX == a_ChunkX) && (itr->m_ChunkZ == a_ChunkZ))
 			{
 				// Already in the queue, bail out
 				return;
@@ -119,7 +132,7 @@ void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkY, int a_Chunk
 		{
 			LOGWARN("WARNING: Adding chunk [%i, %i] to generation queue; Queue is too big! (" SIZE_T_FMT ")", a_ChunkX, a_ChunkZ, m_Queue.size());
 		}
-		m_Queue.push_back(cChunkCoords(a_ChunkX, a_ChunkY, a_ChunkZ));
+		m_Queue.push_back(cChunkCoordsWithBool(a_ChunkX, a_ChunkZ, a_ForceGenerate));
 	}
 
 	m_Event.Set();
@@ -229,9 +242,9 @@ void cChunkGenerator::Execute(void)
 			continue;
 		}
 
-		cChunkCoords coords = m_Queue.front();  // Get next coord from queue
-		m_Queue.erase( m_Queue.begin());  // Remove coordinate from queue
+		cChunkCoordsWithBool coords = m_Queue.front();  // Get next coord from queue
 		bool SkipEnabled = (m_Queue.size() > QUEUE_SKIP_LIMIT);
+		m_Queue.erase(m_Queue.begin());  // Remove coordinate from queue
 		Lock.Unlock();  // Unlock ASAP
 		m_evtRemoved.Set();
 
@@ -245,8 +258,7 @@ void cChunkGenerator::Execute(void)
 			LastReportTick = clock();
 		}
 
-		// Hack for regenerating chunks: if Y != 0, the chunk is considered invalid, even if it has its data set
-		if ((coords.m_ChunkY == 0) && m_ChunkSink->IsChunkValid(coords.m_ChunkX, coords.m_ChunkZ))
+		if (!coords.m_ForceGenerate && m_ChunkSink->IsChunkValid(coords.m_ChunkX, coords.m_ChunkZ))
 		{
 			LOGD("Chunk [%d, %d] already generated, skipping generation", coords.m_ChunkX, coords.m_ChunkZ);
 			// Already generated, ignore request
@@ -259,8 +271,8 @@ void cChunkGenerator::Execute(void)
 			continue;
 		}
 
-		LOGD("Generating chunk [%d, %d, %d]", coords.m_ChunkX, coords.m_ChunkY, coords.m_ChunkZ);
-		DoGenerate(coords.m_ChunkX, coords.m_ChunkY, coords.m_ChunkZ);
+		LOGD("Generating chunk [%d, %d]", coords.m_ChunkX, coords.m_ChunkZ);
+		DoGenerate(coords.m_ChunkX, coords.m_ChunkZ);
 
 		NumChunksGenerated++;
 	}  // while (!bStop)
@@ -269,11 +281,12 @@ void cChunkGenerator::Execute(void)
 
 
 
-void cChunkGenerator::DoGenerate(int a_ChunkX, int a_ChunkY, int a_ChunkZ)
+void cChunkGenerator::DoGenerate(int a_ChunkX, int a_ChunkZ)
 {
 	ASSERT(m_PluginInterface != NULL);
 	ASSERT(m_ChunkSink != NULL);
-	
+	ASSERT(m_ChunkSink->IsChunkQueued(a_ChunkX, a_ChunkZ));
+
 	cChunkDesc ChunkDesc(a_ChunkX, a_ChunkZ);
 	m_PluginInterface->CallHookChunkGenerating(ChunkDesc);
 	m_Generator->DoGenerate(a_ChunkX, a_ChunkZ, ChunkDesc);
diff --git a/src/Generating/ChunkGenerator.h b/src/Generating/ChunkGenerator.h
index 88d71f3f9..190d9e616 100644
--- a/src/Generating/ChunkGenerator.h
+++ b/src/Generating/ChunkGenerator.h
@@ -106,6 +106,10 @@ public:
 		If this callback returns false, the chunk is not generated.
 		*/
 		virtual bool HasChunkAnyClients(int a_ChunkX, int a_ChunkZ) = 0;
+
+		/** Called to check whether the specified chunk is in the queued state.
+		Currently used only in Debug-mode asserts. */
+		virtual bool IsChunkQueued(int a_ChunkX, int a_ChunkZ) = 0;
 	} ;
 	
 
@@ -116,7 +120,7 @@ public:
 	void Stop(void);
 
 	/// Queues the chunk for generation; removes duplicate requests
-	void QueueGenerateChunk(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
+	void QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate);
 	
 	/// Generates the biomes for the specified chunk (directly, not in a separate thread). Used by the world loader if biomes failed loading.
 	void GenerateBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap);
@@ -137,10 +141,10 @@ private:
 
 	int m_Seed;
 
-	cCriticalSection m_CS;
-	cChunkCoordsList m_Queue;
-	cEvent           m_Event;       ///< Set when an item is added to the queue or the thread should terminate
-	cEvent           m_evtRemoved;  ///< Set when an item is removed from the queue
+	cCriticalSection         m_CS;
+	cChunkCoordsWithBoolList m_Queue;
+	cEvent                   m_Event;       ///< Set when an item is added to the queue or the thread should terminate
+	cEvent                   m_evtRemoved;  ///< Set when an item is removed from the queue
 	
 	cGenerator * m_Generator;  ///< The actual generator engine used to generate chunks
 	
@@ -154,7 +158,7 @@ private:
 	// cIsThread override:
 	virtual void Execute(void) override;
 
-	void DoGenerate(int a_ChunkX, int a_ChunkY, int a_ChunkZ);
+	void DoGenerate(int a_ChunkX, int a_ChunkZ);
 };
 
 
diff --git a/src/Generating/ComposableGenerator.cpp b/src/Generating/ComposableGenerator.cpp
index 6f4007d24..69068d231 100644
--- a/src/Generating/ComposableGenerator.cpp
+++ b/src/Generating/ComposableGenerator.cpp
@@ -230,17 +230,29 @@ void cComposableGenerator::InitBiomeGen(cIniFile & a_IniFile)
 	
 	// Add a cache, if requested:
 	int CacheSize = a_IniFile.GetValueSetI("Generator", "BiomeGenCacheSize", CacheOffByDefault ? 0 : 64);
-	if (CacheSize > 0)
+
+	if (CacheSize <= 0)
+	{
+		return;
+	}
+
+	int MultiCacheLength = a_IniFile.GetValueSetI("Generator", "BiomeGenMultiCacheLength", 4);
+	if (CacheSize < 4)
+	{
+		LOGWARNING("Biomegen cache size set too low, would hurt performance instead of helping. Increasing from %d to %d",
+			CacheSize, 4
+		);
+		CacheSize = 4;
+	}
+	LOGD("Using a cache for biomegen of size %d.", CacheSize);
+	m_UnderlyingBiomeGen = m_BiomeGen;
+	if (MultiCacheLength > 0)
+	{
+		LOGD("Enabling multicache for biomegen of length %d.", MultiCacheLength);
+		m_BiomeGen = new cBioGenMulticache(m_UnderlyingBiomeGen, CacheSize, MultiCacheLength);
+	}
+	else
 	{
-		if (CacheSize < 4)
-		{
-			LOGWARNING("Biomegen cache size set too low, would hurt performance instead of helping. Increasing from %d to %d",
-				CacheSize, 4
-			);
-			CacheSize = 4;
-		}
-		LOGD("Using a cache for biomegen of size %d.", CacheSize);
-		m_UnderlyingBiomeGen = m_BiomeGen;
 		m_BiomeGen = new cBioGenCache(m_UnderlyingBiomeGen, CacheSize);
 	}
 }