2 files changed, 63 insertions, 31 deletions

diff --git a/src/Generating/ChunkGenerator.cpp b/src/Generating/ChunkGenerator.cpp
index d2e7b47b4..854aac60d 100644
--- a/src/Generating/ChunkGenerator.cpp
+++ b/src/Generating/ChunkGenerator.cpp
@@ -110,29 +110,19 @@ void cChunkGenerator::Stop(void)
 
 
 
-void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate)
+void cChunkGenerator::QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate, cChunkCoordCallback * a_Callback)
 {
 	ASSERT(m_ChunkSink->IsChunkQueued(a_ChunkX, a_ChunkZ));
 
 	{
 		cCSLock Lock(m_CS);
 
-		// Check if it is already in the queue:
-		for (cChunkCoordsWithBoolList::iterator itr = m_Queue.begin(); itr != m_Queue.end(); ++itr)
-		{
-			if ((itr->m_ChunkX == a_ChunkX) && (itr->m_ChunkZ == a_ChunkZ))
-			{
-				// Already in the queue, bail out
-				return;
-			}
-		}  // for itr - m_Queue[]
-
 		// Add to queue, issue a warning if too many:
 		if (m_Queue.size() >= QUEUE_WARNING_LIMIT)
 		{
 			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(cChunkCoordsWithBool(a_ChunkX, a_ChunkZ, a_ForceGenerate));
+		m_Queue.push_back(cQueueItem{a_ChunkX, a_ChunkZ, a_ForceGenerate, a_Callback});
 	}
 
 	m_Event.Set();
@@ -242,9 +232,9 @@ void cChunkGenerator::Execute(void)
 			continue;
 		}
 
-		cChunkCoordsWithBool coords = m_Queue.front();  // Get next coord from queue
+		cQueueItem item = m_Queue.front();  // Get next chunk from the queue
 		bool SkipEnabled = (m_Queue.size() > QUEUE_SKIP_LIMIT);
-		m_Queue.erase(m_Queue.begin());  // Remove coordinate from queue
+		m_Queue.erase(m_Queue.begin());  // Remove the item from the queue
 		Lock.Unlock();  // Unlock ASAP
 		m_evtRemoved.Set();
 
@@ -258,22 +248,35 @@ void cChunkGenerator::Execute(void)
 			LastReportTick = clock();
 		}
 
-		if (!coords.m_ForceGenerate && m_ChunkSink->IsChunkValid(coords.m_ChunkX, coords.m_ChunkZ))
+		// Skip the chunk if it's already generated and regeneration is not forced:
+		if (!item.m_ForceGenerate && m_ChunkSink->IsChunkValid(item.m_ChunkX, item.m_ChunkZ))
 		{
-			LOGD("Chunk [%d, %d] already generated, skipping generation", coords.m_ChunkX, coords.m_ChunkZ);
-			// Already generated, ignore request
+			LOGD("Chunk [%d, %d] already generated, skipping generation", item.m_ChunkX, item.m_ChunkZ);
+			if (item.m_Callback != nullptr)
+			{
+				item.m_Callback->Call(item.m_ChunkX, item.m_ChunkZ);
+			}
 			continue;
 		}
 
-		if (SkipEnabled && !m_ChunkSink->HasChunkAnyClients(coords.m_ChunkX, coords.m_ChunkZ))
+		// Skip the chunk if the generator is overloaded:
+		if (SkipEnabled && !m_ChunkSink->HasChunkAnyClients(item.m_ChunkX, item.m_ChunkZ))
 		{
-			LOGWARNING("Chunk generator overloaded, skipping chunk [%d, %d]", coords.m_ChunkX, coords.m_ChunkZ);
+			LOGWARNING("Chunk generator overloaded, skipping chunk [%d, %d]", item.m_ChunkX, item.m_ChunkZ);
+			if (item.m_Callback != nullptr)
+			{
+				item.m_Callback->Call(item.m_ChunkX, item.m_ChunkZ);
+			}
 			continue;
 		}
 
-		LOGD("Generating chunk [%d, %d]", coords.m_ChunkX, coords.m_ChunkZ);
-		DoGenerate(coords.m_ChunkX, coords.m_ChunkZ);
-
+		// Generate the chunk:
+		LOGD("Generating chunk [%d, %d]", item.m_ChunkX, item.m_ChunkZ);
+		DoGenerate(item.m_ChunkX, item.m_ChunkZ);
+		if (item.m_Callback != nullptr)
+		{
+			item.m_Callback->Call(item.m_ChunkX, item.m_ChunkZ);
+		}
 		NumChunksGenerated++;
 	}  // while (!bStop)
 }
diff --git a/src/Generating/ChunkGenerator.h b/src/Generating/ChunkGenerator.h
index 190d9e616..4af486ae1 100644
--- a/src/Generating/ChunkGenerator.h
+++ b/src/Generating/ChunkGenerator.h
@@ -119,8 +119,12 @@ public:
 	bool Start(cPluginInterface & a_PluginInterface, cChunkSink & a_ChunkSink, cIniFile & a_IniFile);
 	void Stop(void);
 
-	/// Queues the chunk for generation; removes duplicate requests
-	void QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate);
+	/** Queues the chunk for generation
+	If a-ForceGenerate is set, the chunk is regenerated even if the data is already present in the chunksink.
+	a_Callback is called after the chunk is generated. If the chunk was already present, the callback is still called, even if not regenerating.
+	It is legal to set the callback to nullptr, no callback is called then.
+	If the generator becomes overloaded and skips this chunk, the callback is still called. */
+	void QueueGenerateChunk(int a_ChunkX, int a_ChunkZ, bool a_ForceGenerate, cChunkCoordCallback * a_Callback = nullptr);
 	
 	/// 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);
@@ -131,22 +135,46 @@ public:
 	
 	int GetSeed(void) const { return m_Seed; }
 	
-	/// Returns the biome at the specified coords. Used by ChunkMap if an invalid chunk is queried for biome
+	/** Returns the biome at the specified coords. Used by ChunkMap if an invalid chunk is queried for biome */
 	EMCSBiome GetBiomeAt(int a_BlockX, int a_BlockZ);
 
-	/// Reads a block type from the ini file; returns the blocktype on success, emits a warning and returns a_Default's representation on failure.
+	/** Reads a block type from the ini file; returns the blocktype on success, emits a warning and returns a_Default's representation on failure. */
 	static BLOCKTYPE GetIniBlock(cIniFile & a_IniFile, const AString & a_SectionName, const AString & a_ValueName, const AString & a_Default);
 	
 private:
 
+	struct cQueueItem
+	{
+		/** The chunk coords */
+		int m_ChunkX, m_ChunkZ;
+
+		/** Force the regeneration of an already existing chunk */
+		bool m_ForceGenerate;
+
+		/** Callback to call after generating.*/
+		cChunkCoordCallback * m_Callback;
+	};
+
+	typedef std::list<cQueueItem> cGenQueue;
+
+
+	/** Seed used for the generator. */
 	int m_Seed;
 
-	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
+	/** CS protecting access to the queue. */
+	cCriticalSection m_CS;
+
+	/** Queue of the chunks to be generated. Protected against multithreaded access by m_CS. */
+	cGenQueue m_Queue;
+
+	/** Set when an item is added to the queue or the thread should terminate. */
+	cEvent m_Event;
+
+	/** Set when an item is removed from the queue. */
+	cEvent m_evtRemoved;
 	
-	cGenerator * m_Generator;  ///< The actual generator engine used to generate chunks
+	/** The actual generator engine used to generate chunks. */
+	cGenerator * m_Generator;
 	
 	/** The plugin interface that may modify the generated chunks */
 	cPluginInterface * m_PluginInterface;
@@ -158,6 +186,7 @@ private:
 	// cIsThread override:
 	virtual void Execute(void) override;
 
+	/** Generates the specified chunk and sets it into the chunksink. */
 	void DoGenerate(int a_ChunkX, int a_ChunkZ);
 };