1 files changed, 96 insertions, 0 deletions
diff --git a/BiomeVisualiser/BiomeCache.h b/BiomeVisualiser/BiomeCache.h
new file mode 100644
index 000000000..86602a19d
--- /dev/null
+++ b/BiomeVisualiser/BiomeCache.h
@@ -0,0 +1,96 @@
+
+// BiomeCache.h
+
+// Declares the cBiomeCache class representing a biome source that caches data from the underlying biome source
+
+/*
+This cache works a bit differently than regular caches. 
+It first receives the hint of area that it will need to provide.
+The Cache uses several threads to request biomes from the underlying source to fill that area.
+While the area is being filled, requests for biomes may already come, such requests are answered with baLater if no data yet.
+*/
+
+#pragma once
+
+
+
+
+
+#include "BiomeSource.h"
+#include "../source/OSSupport/IsThread.h"
+
+
+
+
+
+class cBiomeCache :
+	public cBiomeSource
+{
+public:
+	cBiomeCache(void);
+	~cBiomeCache();
+	
+	// cBiomeSource overrides:
+	virtual eAvailability GetBiome(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_Biomes) override;
+	virtual void HintViewArea(int a_MinChunkX, int a_MaxChunkX, int a_MinChunkZ, int a_MaxChunkZ) override;
+	
+	void SetSource(cBiomeSource * a_Source);  // Takes ownership of the source ptr
+	
+protected:
+	class cItem
+	{
+	public:
+		cItem(int a_ChunkX, int a_ChunkZ);
+		
+		int m_ChunkX;
+		int m_ChunkZ;
+		bool m_IsValid;
+		cChunkDef::BiomeMap m_Biomes;
+	} ;
+	
+	typedef cItem * pItem;
+	typedef std::list<pItem> cItems;
+	
+	class cThread :
+		public cIsThread
+	{
+		typedef cIsThread super;
+		
+	public:
+		cThread(cBiomeCache & a_Parent);
+		
+		// cIsThread overrides:
+		virtual void Execute(void) override;
+		
+	protected:
+		cBiomeCache & m_Parent;
+	} ;
+	
+	typedef std::list<cThread *> cThreads;
+	
+	cBiomeSource * m_Source;
+	
+	cCriticalSection m_CS;
+	int     m_BaseX;      ///< MinChunkX for the m_Available rectangle
+	int     m_BaseZ;      ///< MinChunkZ for the m_Available rectangle
+	int     m_Width;      ///< Width of the m_Available rectangle
+	int     m_Height;     ///< Height of the m_Available rectangle
+	pItem * m_Available;  ///< Items that have already been processed (baNow or baNever), [x + m_Width * z]
+	cItems  m_Queue;      ///< Items that are queued for processing (baLater)
+	cItems  m_Pool;       ///< Items that are not needed anymore, can be reused for other coords
+	
+	cEvent m_evtQueued;  // Triggerred when an item is added to m_Queue
+	
+	cThreads m_Threads;  // Threads that update the cache.
+	bool m_IsTerminatingThreads;  // Set to true to indicate to all threads that they should exit
+	
+	/// Removes from a_Items all items that are outside of the given coords, moves those into m_Pool
+	void FilterOutItems(cItems & a_Items, int a_MinChunkX, int a_MaxChunkX, int a_MinChunkZ, int a_MaxChunkZ);
+	
+	/// Processes one item from m_Queue into m_Available. Blocks if m_Queue is empty; respects m_IsTerminatingThreads
+	void thrProcessQueueItem(void);
+} ;
+
+
+
+