adding the multicache behavior

src/Generating/BioGen.cpp

@@ -208,6 +208,121 @@ void cBioGenCache::InitializeBiomeGen(cIniFile & a_IniFile)
 
 
 
+////////////////////////////////////////////////////////////////////////////////
+// cBioGenMulticache:
+
+cBioGenMulticache::cBioGenMulticache(cBiomeGen * a_BioGenToCache, int a_CacheSize, int a_CachesLength) :
+m_BioGenToCache(a_BioGenToCache),
+m_CacheSize(a_CacheSize),
+m_CachesLength(a_CachesLength),
+m_CachesOrder(new int*[a_CachesLength * a_CachesLength]),
+m_CachesData(new sCacheData*[a_CachesLength * a_CachesLength]),
+m_NumHits(0),
+m_NumMisses(0),
+m_TotalChain(0)
+{
+	for (int i = 0; i < m_CachesLength * m_CachesLength; i++) {
+		sCacheData * cacheData = m_CachesData[i] = new sCacheData[m_CacheSize];
+		int * cacheOrder = m_CachesOrder[i] = new int[m_CacheSize];
+
+		for (int j = 0; j < m_CacheSize; j++)
+		{
+			cacheOrder[j] = j;
+			cacheData[j].m_ChunkX = 0x7fffffff;
+			cacheData[j].m_ChunkZ = 0x7fffffff;
+		}
+	}
+
+}
+
+
+
+
+
+cBioGenMulticache::~cBioGenMulticache()
+{
+	for (int i = 0; i < m_CachesLength * m_CachesLength; i++) {
+		delete[] m_CachesData[i];
+		delete[] m_CachesOrder[i];
+	}
+	delete[] m_CachesData;
+	m_CachesData = NULL;
+	delete[] m_CachesOrder;
+	m_CachesOrder = NULL;
+}
+
+
+
+
+
+void cBioGenMulticache::GenBiomes(int a_ChunkX, int a_ChunkZ, cChunkDef::BiomeMap & a_BiomeMap)
+{
+	if (((m_NumHits + m_NumMisses) % 1024) == 10)
+	{
+		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);
+	}
+
+	int cacheIdx = ((unsigned int)a_ChunkX % m_CachesLength) * m_CachesLength + ((unsigned int)a_ChunkZ % m_CachesLength);
+	sCacheData * cacheData = m_CachesData[cacheIdx];
+	int * cacheOrder = m_CachesOrder[cacheIdx];
+
+	for (int i = 0; i < m_CacheSize; i++)
+	{
+		if (
+			(cacheData[cacheOrder[i]].m_ChunkX != a_ChunkX) ||
+			(cacheData[cacheOrder[i]].m_ChunkZ != a_ChunkZ)
+			)
+		{
+			continue;
+		}
+		// Found it in the cache
+		int Idx = cacheOrder[i];
+
+		// Move to front:
+		for (int j = i; j > 0; j--)
+		{
+			cacheOrder[j] = cacheOrder[j - 1];
+		}
+		cacheOrder[0] = Idx;
+
+		// Use the cached data:
+		memcpy(a_BiomeMap, cacheData[Idx].m_BiomeMap, sizeof(a_BiomeMap));
+
+		m_NumHits++;
+		m_TotalChain += i;
+		return;
+	}  // for i - cache
+
+	// Not in the cache:
+	m_NumMisses++;
+	m_BioGenToCache->GenBiomes(a_ChunkX, a_ChunkZ, a_BiomeMap);
+
+	// Insert it as the first item in the MRU order:
+	int Idx = cacheOrder[m_CacheSize - 1];
+	for (int i = m_CacheSize - 1; i > 0; i--)
+	{
+		cacheOrder[i] = cacheOrder[i - 1];
+	}  // for i - m_CacheOrder[]
+	cacheOrder[0] = Idx;
+	memcpy(cacheData[Idx].m_BiomeMap, a_BiomeMap, sizeof(a_BiomeMap));
+	cacheData[Idx].m_ChunkX = a_ChunkX;
+	cacheData[Idx].m_ChunkZ = a_ChunkZ;
+}
+
+
+
+
+
+void cBioGenMulticache::InitializeBiomeGen(cIniFile & a_IniFile)
+{
+	super::InitializeBiomeGen(a_IniFile);
+	m_BioGenToCache->InitializeBiomeGen(a_IniFile);
+}
+
+
+
+
 
 ////////////////////////////////////////////////////////////////////////////////
 // cBiomeGenList:

src/Generating/BioGen.h

@@ -84,7 +84,7 @@ class cBioGenMulticache :
 	typedef cBiomeGen super;
 
 public:
-	cBioGenMulticache(cBiomeGen * a_BioGenToCache, int a_CacheSize, int a_CacheLength);  // Doesn't take ownership of a_BioGenToCache
+	cBioGenMulticache(cBiomeGen * a_BioGenToCache, int a_CacheSize, int a_CachesLength);  // Doesn't take ownership of a_BioGenToCache
 	~cBioGenMulticache();
 
 protected:
@@ -100,9 +100,9 @@ protected:
 
 	// To avoid moving large amounts of data for the MRU behavior, we MRU-ize indices to an array of the actual data
 	int          m_CacheSize;
-	int          m_CacheLength;
+	int          m_CachesLength;
 
-	int **m_CachesOrder; // MRU-ized order, indices into the multiple m_CachesData array
+	int ** m_CachesOrder; // MRU-ized order, indices into the multiple m_CachesData array
 	sCacheData ** m_CachesData; 
 
 	// Cache statistics

src/Generating/ComposableGenerator.cpp

@@ -241,7 +241,7 @@ void cComposableGenerator::InitBiomeGen(cIniFile & a_IniFile)
 		}
 		LOGD("Using a cache for biomegen of size %d.", CacheSize);
 		m_UnderlyingBiomeGen = m_BiomeGen;
-		m_BiomeGen = new cBioGenCache(m_UnderlyingBiomeGen, CacheSize);
+		m_BiomeGen = new cBioGenMulticache(m_UnderlyingBiomeGen, CacheSize, 4);
 	}
 }