FastRandom rewrite (#3754)

src/BlockEntities/DropSpenserEntity.cpp

@@ -174,7 +174,7 @@ void cDropSpenserEntity::DropFromSlot(cChunk & a_Chunk, int a_SlotNum)
 	cItems Pickups;
 	Pickups.push_back(m_Contents.RemoveOneItem(a_SlotNum));
 
-	const int PickupSpeed = m_World->GetTickRandomNumber(4) + 2;  // At least 2, at most 6
+	const int PickupSpeed = GetRandomProvider().RandInt(2, 6);  // At least 2, at most 6
 	int PickupSpeedX = 0, PickupSpeedY = 0, PickupSpeedZ = 0;
 	switch (Meta & E_META_DROPSPENSER_FACING_MASK)
 	{

src/BlockEntities/MobSpawnerEntity.cpp

@@ -107,7 +107,7 @@ bool cMobSpawnerEntity::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 
 void cMobSpawnerEntity::ResetTimer(void)
 {
-	m_SpawnDelay = static_cast<short>(200 + m_World->GetTickRandomNumber(600));
+	m_SpawnDelay = GetRandomProvider().RandInt<short>(200, 800);
 	m_World->BroadcastBlockEntity(m_PosX, m_PosY, m_PosZ);
 }
 
@@ -138,7 +138,7 @@ void cMobSpawnerEntity::SpawnEntity(void)
 
 		virtual bool Item(cChunk * a_Chunk)
 		{
-			cFastRandom Random;
+			auto & Random = GetRandomProvider();
 
 			bool EntitiesSpawned = false;
 			for (size_t i = 0; i < 4; i++)
@@ -148,9 +148,9 @@ void cMobSpawnerEntity::SpawnEntity(void)
 					break;
 				}
 
-				int RelX = static_cast<int>(m_RelX + static_cast<double>(Random.NextFloat() - Random.NextFloat()) * 4.0);
+				int RelX = m_RelX + static_cast<int>((Random.RandReal<double>() - Random.RandReal<double>()) * 4.0);
-				int RelY = m_RelY + Random.NextInt(3) - 1;
+				int RelY = m_RelY + Random.RandInt(-1, 1);
-				int RelZ = static_cast<int>(m_RelZ + static_cast<double>(Random.NextFloat() - Random.NextFloat()) * 4.0);
+				int RelZ = m_RelZ + static_cast<int>((Random.RandReal<double>() - Random.RandReal<double>()) * 4.0);
 
 				cChunk * Chunk = a_Chunk->GetRelNeighborChunkAdjustCoords(RelX, RelZ);
 				if ((Chunk == nullptr) || !Chunk->IsValid())
@@ -171,7 +171,7 @@ void cMobSpawnerEntity::SpawnEntity(void)
 					}
 
 					Monster->SetPosition(PosX, RelY, PosZ);
-					Monster->SetYaw(Random.NextFloat() * 360.0f);
+					Monster->SetYaw(Random.RandReal(360.0f));
 					if (Chunk->GetWorld()->SpawnMobFinalize(Monster) != cEntity::INVALID_ID)
 					{
 						EntitiesSpawned = true;

src/Blocks/BlockBigFlower.h

@@ -67,8 +67,7 @@ public:
 				)
 			)
 			{
-				MTRand r1;
+				if (GetRandomProvider().RandBool(0.10))
-				if (r1.randInt(10) == 5)
 				{
 					cItems Pickups;
 					if (FlowerMeta == E_META_BIG_FLOWER_DOUBLE_TALL_GRASS)

src/Blocks/BlockCocoaPod.h

@@ -30,9 +30,7 @@ public:
 
 	virtual void OnUpdate(cChunkInterface & cChunkInterface, cWorldInterface & a_WorldInterface, cBlockPluginInterface & a_PluginInterface, cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ) override
 	{
-		cFastRandom Random;
+		if (GetRandomProvider().RandBool(0.20))
-
-		if (Random.NextInt(5) == 0)
 		{
 			NIBBLETYPE Meta = a_Chunk.GetMeta(a_RelX, a_RelY, a_RelZ);
 			NIBBLETYPE TypeMeta = Meta & 0x03;

src/Blocks/BlockCrops.h

@@ -26,7 +26,7 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_Meta) override
 	{
-		cFastRandom rand;
+		auto & rand = GetRandomProvider();
 
 		// If not fully grown, drop the "seed" of whatever is growing:
 		if (a_Meta < RipeMeta)
@@ -51,30 +51,30 @@ public:
 		{
 			case E_BLOCK_BEETROOTS:
 			{
-				char SeedCount = static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3)) / 2);  // [1 .. 3] with high preference of 2
+				char SeedCount = 1 + ((rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2);  // [1 .. 3] with high preference of 2
-				a_Pickups.push_back(cItem(E_ITEM_BEETROOT_SEEDS, SeedCount, 0));
+				a_Pickups.emplace_back(E_ITEM_BEETROOT_SEEDS, SeedCount, 0);
-				char BeetrootCount = static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3)) / 2);  // [1 .. 3] with high preference of 2
+				char BeetrootCount = 1 + ((rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2);  // [1 .. 3] with high preference of 2
-				a_Pickups.push_back(cItem(E_ITEM_BEETROOT, BeetrootCount, 0));
+				a_Pickups.emplace_back(E_ITEM_BEETROOT, BeetrootCount, 0);
 				break;
 			}
 			case E_BLOCK_CROPS:
 			{
-				a_Pickups.push_back(cItem(E_ITEM_WHEAT, 1, 0));
+				a_Pickups.emplace_back(E_ITEM_WHEAT, 1, 0);
-				a_Pickups.push_back(cItem(E_ITEM_SEEDS, static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3)) / 2), 0));  // [1 .. 3] with high preference of 2
+				a_Pickups.emplace_back(E_ITEM_SEEDS, 1 + ((rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2), 0);  // [1 .. 3] with high preference of 2
 				break;
 			}
 			case E_BLOCK_CARROTS:
 			{
-				a_Pickups.push_back(cItem(E_ITEM_CARROT, static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3)) / 2), 0));  // [1 .. 3] with high preference of 2
+				a_Pickups.emplace_back(E_ITEM_CARROT, 1 + ((rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2), 0);  // [1 .. 3] with high preference of 2
 				break;
 			}
 			case E_BLOCK_POTATOES:
 			{
-				a_Pickups.push_back(cItem(E_ITEM_POTATO, static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3)) / 2), 0));  // [1 .. 3] with high preference of 2
+				a_Pickups.emplace_back(E_ITEM_POTATO, 1 + ((rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2), 0);  // [1 .. 3] with high preference of 2
-				if (rand.NextInt(21) == 0)
+				if (rand.RandBool(0.05))
 				{
 					// With a 5% chance, drop a poisonous potato as well
-					a_Pickups.push_back(cItem(E_ITEM_POISONOUS_POTATO, 1, 0));
+					a_Pickups.emplace_back(E_ITEM_POISONOUS_POTATO, 1, 0);
 				}
 				break;
 			}

src/Blocks/BlockDeadBush.h

@@ -46,11 +46,10 @@ public:
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
 		// Drop 0-3 sticks
-		cFastRandom random;
+		char chance = GetRandomProvider().RandInt<char>(3);
-		int chance = random.NextInt(3);
 		if (chance != 0)
 		{
-			a_Pickups.push_back(cItem(E_ITEM_STICK, static_cast<char>(chance), 0));
+			a_Pickups.emplace_back(E_ITEM_STICK, chance, 0);
 		}
 	}
 
@@ -74,7 +73,7 @@ public:
 			// Spawn the pickups:
 			if (!Drops.empty())
 			{
-				MTRand r1;
+				auto & r1 = GetRandomProvider();
 
 				// Mid-block position first
 				double MicroX, MicroY, MicroZ;
@@ -83,8 +82,8 @@ public:
 				MicroZ = a_BlockZ + 0.5;
 
 				// Add random offset second
-				MicroX += r1.rand(1) - 0.5;
+				MicroX += r1.RandReal<double>(-0.5, 0.5);
-				MicroZ += r1.rand(1) - 0.5;
+				MicroZ += r1.RandReal<double>(-0.5, 0.5);
 
 				a_WorldInterface.SpawnItemPickups(Drops, MicroX, MicroY, MicroZ);
 			}

src/Blocks/BlockDirt.h

@@ -70,12 +70,12 @@ public:
 		}
 
 		// Grass spreads to adjacent dirt blocks:
-		cFastRandom rand;
+		auto & rand = GetRandomProvider();
 		for (int i = 0; i < 2; i++)  // Pick two blocks to grow to
 		{
-			int OfsX = rand.NextInt(3) - 1;  // [-1 .. 1]
+			int OfsX = rand.RandInt(-1, 1);
-			int OfsY = rand.NextInt(5) - 3;  // [-3 .. 1]
+			int OfsY = rand.RandInt(-3, 1);
-			int OfsZ = rand.NextInt(3) - 1;  // [-1 .. 1]
+			int OfsZ = rand.RandInt(-1, 1);
 
 			BLOCKTYPE  DestBlock;
 			NIBBLETYPE DestMeta;

src/Blocks/BlockGlowstone.h

@@ -18,10 +18,8 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
-		cFastRandom Random;
-
 		// Add more than one dust
-		a_Pickups.push_back(cItem(E_ITEM_GLOWSTONE_DUST, static_cast<char>(2 + Random.NextInt(3)), 0));
+		a_Pickups.emplace_back(E_ITEM_GLOWSTONE_DUST, GetRandomProvider().RandInt<char>(2, 4), 0);
 	}
 
 	virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) override

src/Blocks/BlockGravel.h

@@ -18,8 +18,7 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
-		cFastRandom Random;
+		if (GetRandomProvider().RandBool(0.10))
-		if (Random.NextInt(10) == 0)
 		{
 			a_Pickups.Add(E_ITEM_FLINT, 1, 0);
 		}

src/Blocks/BlockHandler.cpp

@@ -526,7 +526,7 @@ void cBlockHandler::DropBlock(cChunkInterface & a_ChunkInterface, cWorldInterfac
 
 	if (!Pickups.empty())
 	{
-		MTRand r1;
+		auto & r1 = GetRandomProvider();
 
 		// Mid-block position first
 		double MicroX, MicroY, MicroZ;
@@ -535,8 +535,8 @@ void cBlockHandler::DropBlock(cChunkInterface & a_ChunkInterface, cWorldInterfac
 		MicroZ = a_BlockZ + 0.5;
 
 		// Add random offset second
-		MicroX += r1.rand(1) - 0.5;
+		MicroX += r1.RandReal<double>(-0.5, 0.5);
-		MicroZ += r1.rand(1) - 0.5;
+		MicroZ += r1.RandReal<double>(-0.5, 0.5);
 
 		a_WorldInterface.SpawnItemPickups(Pickups, MicroX, MicroY, MicroZ);
 	}

src/Blocks/BlockLeaves.h

@@ -37,22 +37,22 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
-		cFastRandom rand;
+		auto & rand = GetRandomProvider();
 
 		// There is a chance to drop a sapling that varies depending on the type of leaf broken.
 		// TODO: Take into account fortune for sapling drops.
-		int chance;
+		double chance = 0.0;
 		if ((m_BlockType == E_BLOCK_LEAVES) && ((a_BlockMeta & 0x03) == E_META_LEAVES_JUNGLE))
 		{
 			// Jungle leaves have a 2.5% chance of dropping a sapling.
-			chance = rand.NextInt(40);
+			chance = 0.025;
 		}
 		else
 		{
 			// Other leaves have a 5% chance of dropping a sapling.
-			chance = rand.NextInt(20);
+			chance = 0.05;
 		}
-		if (chance == 0)
+		if (rand.RandBool(chance))
 		{
 			a_Pickups.push_back(
 				cItem(
@@ -66,7 +66,7 @@ public:
 		// 0.5 % chance of dropping an apple, if the leaves' type is Apple Leaves
 		if ((m_BlockType == E_BLOCK_LEAVES) && ((a_BlockMeta & 0x03) == E_META_LEAVES_APPLE))
 		{
-			if (rand.NextInt(200) == 0)
+			if (rand.RandBool(0.005))
 			{
 				a_Pickups.push_back(cItem(E_ITEM_RED_APPLE, 1, 0));
 			}

src/Blocks/BlockMelon.h

@@ -18,8 +18,7 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
-		cFastRandom Random;
+		a_Pickups.emplace_back(E_ITEM_MELON_SLICE, GetRandomProvider().RandInt<char>(3, 7), 0);
-		a_Pickups.push_back(cItem(E_ITEM_MELON_SLICE, static_cast<char>(3 + Random.NextInt(5)), 0));
 	}
 
 	virtual ColourID GetMapBaseColourID(NIBBLETYPE a_Meta) override

src/Blocks/BlockMobHead.h

@@ -42,7 +42,7 @@ public:
 
 				cItems Pickups;
 				Pickups.Add(E_ITEM_HEAD, 1, static_cast<short>(MobHeadEntity->GetType()));
-				MTRand r1;
+				auto & r1 = GetRandomProvider();
 
 				// Mid-block position first
 				double MicroX, MicroY, MicroZ;
@@ -51,8 +51,8 @@ public:
 				MicroZ = MobHeadEntity->GetPosZ() + 0.5;
 
 				// Add random offset second
-				MicroX += r1.rand(1) - 0.5;
+				MicroX += r1.RandReal<double>(-0.5, 0.5);
-				MicroZ += r1.rand(1) - 0.5;
+				MicroZ += r1.RandReal<double>(-0.5, 0.5);
 
 				MobHeadEntity->GetWorld()->SpawnItemPickups(Pickups, MicroX, MicroY, MicroZ);
 				return false;

src/Blocks/BlockMobSpawner.h

@@ -45,8 +45,8 @@ public:
 			return;
 		}
 
-		cFastRandom Random;
+		auto & Random = GetRandomProvider();
-		int Reward = 15 + Random.NextInt(15) + Random.NextInt(15);
+		int Reward = 15 + Random.RandInt(14) + Random.RandInt(14);
 		a_WorldInterface.SpawnExperienceOrb(static_cast<double>(a_BlockX), static_cast<double>(a_BlockY + 1), static_cast<double>(a_BlockZ), Reward);
 	}
 } ;

src/Blocks/BlockNetherWart.h

@@ -21,12 +21,12 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_Meta) override
 	{
-		cFastRandom rand;
+		auto & rand = GetRandomProvider();
 
 		if (a_Meta == 0x3)
 		{
 			// Fully grown, drop the entire produce:
-			a_Pickups.push_back(cItem(E_ITEM_NETHER_WART, static_cast<char>(1 + (rand.NextInt(3) + rand.NextInt(3))) / 2, 0));
+			a_Pickups.emplace_back(E_ITEM_NETHER_WART, 1 + (rand.RandInt<char>(2) + rand.RandInt<char>(2)) / 2, 0);
 		}
 		else
 		{

src/Blocks/BlockOre.h

@@ -20,19 +20,19 @@ public:
 
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
-		cFastRandom Random;
+		auto & Random = GetRandomProvider();
 
 		switch (m_BlockType)
 		{
 			case E_BLOCK_LAPIS_ORE:
 			{
-				a_Pickups.push_back(cItem(E_ITEM_DYE, static_cast<char>(4 + Random.NextInt(5)), 4));
+				a_Pickups.emplace_back(E_ITEM_DYE, Random.RandInt<char>(4, 8), 4);
 				break;
 			}
 			case E_BLOCK_REDSTONE_ORE:
 			case E_BLOCK_REDSTONE_ORE_GLOWING:
 			{
-				a_Pickups.push_back(cItem(E_ITEM_REDSTONE_DUST, static_cast<char>(4 + Random.NextInt(2)), 0));
+				a_Pickups.emplace_back(E_ITEM_REDSTONE_DUST,  Random.RandInt<char>(4, 5), 0);
 				break;
 			}
 			case E_BLOCK_DIAMOND_ORE:
@@ -84,7 +84,7 @@ public:
 			return;
 		}
 
-		cFastRandom Random;
+		auto & Random = GetRandomProvider();
 		int Reward = 0;
 
 		switch (m_BlockType)
@@ -93,27 +93,27 @@ public:
 			case E_BLOCK_LAPIS_ORE:
 			{
 				// Lapis and nether quartz get 2 - 5 experience
-				Reward = Random.NextInt(4) + 2;
+				Reward = Random.RandInt(2, 5);
 				break;
 			}
 			case E_BLOCK_REDSTONE_ORE:
 			case E_BLOCK_REDSTONE_ORE_GLOWING:
 			{
 				// Redstone gets 1 - 5 experience
-				Reward = Random.NextInt(5) + 1;
+				Reward = Random.RandInt(1, 5);
 				break;
 			}
 			case E_BLOCK_DIAMOND_ORE:
 			case E_BLOCK_EMERALD_ORE:
 			{
 				// Diamond and emerald get 3 - 7 experience
-				Reward = Random.NextInt(5) + 3;
+				Reward = Random.RandInt(3, 7);
 				break;
 			}
 			case E_BLOCK_COAL_ORE:
 			{
 				// Coal gets 0 - 2 experience
-				Reward = Random.NextInt(3);
+				Reward = Random.RandInt(2);
 				break;
 			}
 

src/Blocks/BlockPlant.h

@@ -75,10 +75,9 @@ protected:
 	*/
 	virtual PlantAction CanGrow(cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ)
 	{
-		cFastRandom rand;
 		// Plant can grow if it has the required amount of light, and it passes a random chance based on surrounding blocks
 		PlantAction Action = HasEnoughLight(a_Chunk, a_RelX, a_RelY, a_RelZ);
-		if ((Action == paGrowth) && (rand.NextInt(GetGrowthChance(a_Chunk, a_RelX, a_RelY, a_RelZ)) != 0))
+		if ((Action == paGrowth) && !GetRandomProvider().RandBool(1.0 / GetGrowthChance(a_Chunk, a_RelX, a_RelY, a_RelZ)))
 		{
 			Action = paStay;
 		}

src/Blocks/BlockPortal.h

@@ -40,8 +40,7 @@ public:
 
 	virtual void OnUpdate(cChunkInterface & cChunkInterface, cWorldInterface & a_WorldInterface, cBlockPluginInterface & a_PluginInterface, cChunk & a_Chunk, int a_RelX, int a_RelY, int a_RelZ) override
 	{
-		cFastRandom Random;
+		if (GetRandomProvider().RandBool(0.9995))
-		if (Random.NextInt(2000) != 0)
 		{
 			return;
 		}

src/Blocks/BlockSapling.h

@@ -37,16 +37,16 @@ public:
 		// Only grow if we have the right amount of light
 		if (Light > 8)
 		{
-			cFastRandom random;
+			auto & random = GetRandomProvider();
 			// Only grow if we are in the right growth stage and have the right amount of space around them.
-			if (((Meta & 0x08) != 0) && (random.NextInt(99) < 45) && CanGrowAt(a_Chunk, a_RelX, a_RelY, a_RelZ, Meta))
+			if (((Meta & 0x08) != 0) && random.RandBool(0.45) && CanGrowAt(a_Chunk, a_RelX, a_RelY, a_RelZ, Meta))
 			{
 				int BlockX = a_RelX + a_Chunk.GetPosX() * cChunkDef::Width;
 				int BlockZ = a_RelZ + a_Chunk.GetPosZ() * cChunkDef::Width;
 				a_Chunk.GetWorld()->GrowTree(BlockX, a_RelY, BlockZ);
 			}
 			// Only move to the next growth stage if we haven't gone there yet
-			else if (((Meta & 0x08) == 0) && (random.NextInt(99) < 45))
+			else if (((Meta & 0x08) == 0) && random.RandBool(0.45))
 			{
 				a_Chunk.SetMeta(a_RelX, a_RelY, a_RelZ, Meta | 0x08);
 			}

src/Blocks/BlockSeaLantern.h

@@ -20,8 +20,7 @@ public:
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
 		// Reset meta to 0
-		cFastRandom Random;
+		a_Pickups.emplace_back(E_ITEM_PRISMARINE_CRYSTALS, GetRandomProvider().RandInt<char>(2, 3), 0);
-		a_Pickups.push_back(cItem(E_ITEM_PRISMARINE_CRYSTALS, static_cast<char>(2 + Random.NextInt(2)), 0));
 	}
 } ;
 

src/Blocks/BlockTallGrass.h

@@ -26,8 +26,7 @@ public:
 	virtual void ConvertToPickups(cItems & a_Pickups, NIBBLETYPE a_BlockMeta) override
 	{
 		// Drop seeds, sometimes
-		cFastRandom Random;
+		if (GetRandomProvider().RandBool(0.125))
-		if (Random.NextInt(8) == 0)
 		{
 			a_Pickups.push_back(cItem(E_ITEM_SEEDS, 1, 0));
 		}
@@ -47,7 +46,7 @@ public:
 			// Spawn the pickups:
 			if (!Drops.empty())
 			{
-				MTRand r1;
+				auto & r1 = GetRandomProvider();
 
 				// Mid-block position first
 				double MicroX, MicroY, MicroZ;
@@ -56,8 +55,8 @@ public:
 				MicroZ = a_BlockZ + 0.5;
 
 				// Add random offset second
-				MicroX += r1.rand(1) - 0.5;
+				MicroX += r1.RandReal<double>(-0.5, 0.5);
-				MicroZ += r1.rand(1) - 0.5;
+				MicroZ += r1.RandReal<double>(-0.5, 0.5);
 
 				a_WorldInterface.SpawnItemPickups(Drops, MicroX, MicroY, MicroZ);
 			}

src/Chunk.cpp

@@ -507,14 +507,19 @@ void cChunk::CollectMobCensus(cMobCensus & toFill)
 
 void cChunk::GetThreeRandomNumbers(int & a_X, int & a_Y, int & a_Z, int a_MaxX, int a_MaxY, int a_MaxZ)
 {
-	ASSERT(a_MaxX * a_MaxY * a_MaxZ * 8 < 0x00ffffff);
+	ASSERT(
-	int Random = m_World->GetTickRandomNumber(0x00ffffff);
+		(a_MaxX > 0) && (a_MaxY > 0) && (a_MaxZ > 0) &&
-	a_X =   Random % (a_MaxX * 2);
+		(a_MaxX <= std::numeric_limits<int>::max() / a_MaxY) &&  // a_MaxX * a_MaxY doesn't overflow
-	a_Y =  (Random / (a_MaxX * 2)) % (a_MaxY * 2);
+		(a_MaxX * a_MaxY <= std::numeric_limits<int>::max() / a_MaxZ)  // a_MaxX * a_MaxY * a_MaxZ doesn't overflow
-	a_Z = ((Random / (a_MaxX * 2)) / (a_MaxY * 2)) % (a_MaxZ * 2);
+	);
-	a_X /= 2;
+
-	a_Y /= 2;
+	// MTRand gives an inclusive range [0, Max] but this gives the exclusive range [0, Max)
-	a_Z /= 2;
+	int OverallMax = (a_MaxX - 1) * (a_MaxY - 1) * (a_MaxZ - 1);
+	int Random = m_World->GetTickRandomNumber(OverallMax);
+
+	a_X =   Random % a_MaxX;
+	a_Y =  (Random / a_MaxX) % a_MaxY;
+	a_Z = ((Random / a_MaxX) / a_MaxY) % a_MaxZ;
 }
 
 
@@ -848,7 +853,7 @@ void cChunk::TickBlocks(void)
 void cChunk::ApplyWeatherToTop()
 {
 	if (
-		(m_World->GetTickRandomNumber(100) != 0) ||
+		(GetRandomProvider().RandBool(0.99)) ||
 		(
 			(m_World->GetWeather() != eWeather_Rain) &&
 			(m_World->GetWeather() != eWeather_ThunderStorm)
@@ -932,8 +937,10 @@ void cChunk::ApplyWeatherToTop()
 
 
 
-bool cChunk::GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, MTRand & a_TickRandom)
+bool cChunk::GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType)
 {
+	auto & Random = GetRandomProvider();
+
 	// Convert the stem BlockType into produce BlockType
 	BLOCKTYPE ProduceType;
 	switch (a_BlockType)
@@ -969,7 +976,7 @@ bool cChunk::GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_Bl
 
 	// Pick a direction in which to place the produce:
 	int x = 0, z = 0;
-	int CheckType = a_TickRandom.randInt(3);  // The index to the neighbors array which should be checked for emptiness
+	int CheckType = Random.RandInt(3);  // The index to the neighbors array which should be checked for emptiness
 	switch (CheckType)
 	{
 		case 0: x =  1; break;
@@ -1001,7 +1008,7 @@ bool cChunk::GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_Bl
 		case E_BLOCK_FARMLAND:
 		{
 			// Place a randomly-facing produce:
-			NIBBLETYPE Meta = (ProduceType == E_BLOCK_MELON) ? 0 : static_cast<NIBBLETYPE>(a_TickRandom.randInt(4) % 4);
+			NIBBLETYPE Meta = (ProduceType == E_BLOCK_MELON) ? 0 : static_cast<NIBBLETYPE>(Random.RandInt(4) % 4);
 			LOGD("Growing melon / pumpkin at {%d, %d, %d} (<%d, %d> from stem), overwriting %s, growing on top of %s, meta %d",
 				a_RelX + x + m_PosX * cChunkDef::Width, a_RelY, a_RelZ + z + m_PosZ * cChunkDef::Width,
 				x, z,

src/Chunk.h

@@ -27,7 +27,6 @@ namespace Json
 class cWorld;
 class cClientHandle;
 class cServer;
-class MTRand;
 class cPlayer;
 class cChunkMap;
 class cBeaconEntity;
@@ -609,7 +608,7 @@ private:
 	bool GrowTallGrass      (int a_RelX, int a_RelY, int a_RelZ);
 
 	/** Grows a melon or a pumpkin next to the block specified (assumed to be the stem); returns true if the pumpkin or melon sucessfully grew */
-	bool GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType, MTRand & a_Random);
+	bool GrowMelonPumpkin(int a_RelX, int a_RelY, int a_RelZ, BLOCKTYPE a_BlockType);
 
 	/** Called by Tick() when an entity moves out of this chunk into a neighbor; moves the entity and sends spawn / despawn packet to clients */
 	void MoveEntityToNewChunk(cEntity * a_Entity);

src/ChunkMap.cpp

@@ -1735,7 +1735,7 @@ void cChunkMap::DoExplosionAt(double a_ExplosionSize, double a_BlockX, double a_
 						case E_BLOCK_TNT:
 						{
 							// Activate the TNT, with a random fuse between 10 to 30 game ticks
-							int FuseTime = 10 + m_World->GetTickRandomNumber(20);
+							int FuseTime = GetRandomProvider().RandInt(10, 30);
 							m_World->SpawnPrimedTNT(a_BlockX + x + 0.5, a_BlockY + y + 0.5, a_BlockZ + z + 0.5, FuseTime);
 							area.SetBlockTypeMeta(bx + x, by + y, bz + z, E_BLOCK_AIR, 0);
 							a_BlocksAffected.push_back(Vector3i(bx + x, by + y, bz + z));
@@ -1775,7 +1775,8 @@ void cChunkMap::DoExplosionAt(double a_ExplosionSize, double a_BlockX, double a_
 
 						default:
 						{
-							if (m_World->GetTickRandomNumber(100) <= 25)  // 25% chance of pickups
+							auto & Random = GetRandomProvider();
+							if (Random.RandBool(0.25))  // 25% chance of pickups
 							{
 								cItems Drops;
 								cBlockHandler * Handler = BlockHandler(Block);
@@ -1783,7 +1784,7 @@ void cChunkMap::DoExplosionAt(double a_ExplosionSize, double a_BlockX, double a_
 								Handler->ConvertToPickups(Drops, area.GetBlockMeta(bx + x, by + y, bz + z));  // Stone becomes cobblestone, coal ore becomes coal, etc.
 								m_World->SpawnItemPickups(Drops, bx + x, by + y, bz + z);
 							}
-							else if ((m_World->GetTNTShrapnelLevel() > slNone) && (m_World->GetTickRandomNumber(100) < 20))  // 20% chance of flinging stuff around
+							else if ((m_World->GetTNTShrapnelLevel() > slNone) && Random.RandBool(0.20))  // 20% chance of flinging stuff around
 							{
 								// If the block is shrapnel-able, make a falling block entity out of it:
 								if (
@@ -2516,7 +2517,7 @@ void cChunkMap::GetChunkStats(int & a_NumChunksValid, int & a_NumChunksDirty)
 
 
 
-bool cChunkMap::GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, MTRand & a_Rand)
+bool cChunkMap::GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType)
 {
 	int ChunkX, ChunkZ;
 	cChunkDef::AbsoluteToRelative(a_BlockX, a_BlockY, a_BlockZ, ChunkX, ChunkZ);
@@ -2525,7 +2526,7 @@ bool cChunkMap::GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCK
 	cChunkPtr Chunk = GetChunkNoLoad(ChunkX, ChunkZ);
 	if (Chunk != nullptr)
 	{
-		return Chunk->GrowMelonPumpkin(a_BlockX, a_BlockY, a_BlockZ, a_BlockType, a_Rand);
+		return Chunk->GrowMelonPumpkin(a_BlockX, a_BlockY, a_BlockZ, a_BlockType);
 	}
 	return false;
 }

src/ChunkMap.h

@@ -15,7 +15,6 @@
 class cWorld;
 class cWorldInterface;
 class cItem;
-class MTRand;
 class cChunkStay;
 class cChunk;
 class cPlayer;
@@ -362,7 +361,7 @@ public:
 	void GetChunkStats(int & a_NumChunksValid, int & a_NumChunksDirty);
 
 	/** Grows a melon or a pumpkin next to the block specified (assumed to be the stem); returns true if the pumpkin or melon sucessfully grew */
-	bool GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType, MTRand & a_Rand);
+	bool GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType);
 
 	/** Grows a sugarcane present at the block specified by the amount of blocks specified, up to the max height specified in the config; returns the amount of blocks the sugarcane grew inside this call */
 	int GrowSugarcane(int a_BlockX, int a_BlockY, int a_BlockZ, int a_NumBlocksToGrow);

src/Enchantments.cpp

@@ -1012,14 +1012,12 @@ void cEnchantments::CheckEnchantmentConflictsFromVector(cWeightedEnchantments &
 
 cEnchantments cEnchantments::GetRandomEnchantmentFromVector(cWeightedEnchantments & a_Enchantments)
 {
-	cFastRandom Random;
-
 	int AllWeights = 0;
 	for (cWeightedEnchantments::iterator it = a_Enchantments.begin(); it != a_Enchantments.end(); ++it)
 	{
 		AllWeights += (*it).m_Weight;
 	}
-	int RandomNumber = Random.GenerateRandomInteger(0, AllWeights - 1);
+	int RandomNumber = GetRandomProvider().RandInt(AllWeights - 1);
 	for (cWeightedEnchantments::iterator it = a_Enchantments.begin(); it != a_Enchantments.end(); ++it)
 	{
 		RandomNumber -= (*it).m_Weight;

src/Entities/Entity.cpp

@@ -495,12 +495,11 @@ bool cEntity::DoTakeDamage(TakeDamageInfo & a_TDI)
 		{
 			int Chance = static_cast<int>(ThornsLevel * 15);
 
-			cFastRandom Random;
+			auto & Random = GetRandomProvider();
-			int RandomValue = Random.GenerateRandomInteger(0, 100);
 
-			if (RandomValue <= Chance)
+			if (Random.RandBool(Chance / 100.0))
 			{
-				a_TDI.Attacker->TakeDamage(dtAttack, this, 0, Random.GenerateRandomInteger(1, 4), 0);
+				a_TDI.Attacker->TakeDamage(dtAttack, this, 0, Random.RandInt(1, 4), 0);
 			}
 		}
 
@@ -574,8 +573,7 @@ bool cEntity::DoTakeDamage(TakeDamageInfo & a_TDI)
 			TotalEPF = 25;
 		}
 
-		cFastRandom Random;
+		float RandomValue = GetRandomProvider().RandReal(0.5f, 1.0f);
-		float RandomValue = Random.GenerateRandomInteger(50, 100) * 0.01f;
 
 		TotalEPF = ceil(TotalEPF * RandomValue);
 

src/Entities/ExpBottleEntity.cpp

@@ -40,6 +40,6 @@ void cExpBottleEntity::Break(const Vector3d &a_HitPos)
 {
 	// Spawn an experience orb with a reward between 3 and 11.
 	m_World->BroadcastSoundParticleEffect(EffectID::PARTICLE_SPLASH_POTION, POSX_TOINT, POSY_TOINT, POSZ_TOINT, 0);
-	m_World->SpawnExperienceOrb(GetPosX(), GetPosY(), GetPosZ(), 3 + m_World->GetTickRandomNumber(8));
+	m_World->SpawnExperienceOrb(GetPosX(), GetPosY(), GetPosZ(), GetRandomProvider().RandInt(3, 11));
 	Destroy();
 }

src/Entities/Floater.cpp

@@ -128,6 +128,8 @@ void cFloater::SpawnOn(cClientHandle & a_Client)
 
 void cFloater::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 {
+	auto & Random = GetRandomProvider();
+
 	HandlePhysics(a_Dt, a_Chunk);
 	if (IsBlockWater(m_World->GetBlock(POSX_TOINT, POSY_TOINT, POSZ_TOINT))
 		&& (m_World->GetBlockMeta(POSX_TOINT, POSY_TOINT, POSX_TOINT) == 0))
@@ -141,13 +143,13 @@ void cFloater::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 				SetPosY(GetPosY() - 1);
 				m_CanPickupItem = true;
 				m_PickupCountDown = 20;
-				m_CountDownTime = 100 + m_World->GetTickRandomNumber(800);
+				m_CountDownTime = Random.RandInt(100, 900);
 				LOGD("Floater %i can be picked up", GetUniqueID());
 			}
 			else if (m_CountDownTime == 20)  // Calculate the position where the particles should spawn and start producing them.
 			{
 				LOGD("Started producing particles for floater %i", GetUniqueID());
-				m_ParticlePos.Set(GetPosX() + (-4 + m_World->GetTickRandomNumber(8)), GetPosY(), GetPosZ() + (-4 + m_World->GetTickRandomNumber(8)));
+				m_ParticlePos.Set(GetPosX() + Random.RandInt(-4, 4), GetPosY(), GetPosZ() + Random.RandInt(-4, 4));
 				m_World->GetBroadcaster().BroadcastParticleEffect("splash", static_cast<Vector3f>(m_ParticlePos), Vector3f{}, 0, 15);
 			}
 			else if (m_CountDownTime < 20)
@@ -159,14 +161,14 @@ void cFloater::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 			m_CountDownTime--;
 			if (m_World->GetHeight(POSX_TOINT, POSZ_TOINT) == POSY_TOINT)
 			{
-				if (m_World->IsWeatherWet() && m_World->GetTickRandomNumber(3) == 0)  // 25% chance of an extra countdown when being rained on.
+				if (m_World->IsWeatherWet() && Random.RandBool(0.25))  // 25% chance of an extra countdown when being rained on.
 				{
 					m_CountDownTime--;
 				}
 			}
 			else  // if the floater is underground it has a 50% chance of not decreasing the countdown.
 			{
-				if (m_World->GetTickRandomNumber(1) == 0)
+				if (Random.RandBool())
 				{
 					m_CountDownTime++;
 				}

src/Entities/Player.cpp

@@ -1069,9 +1069,9 @@ void cPlayer::KilledBy(TakeDamageInfo & a_TDI)
 		{
 			case dtRangedAttack: DamageText = "was shot"; break;
 			case dtLightning: DamageText = "was plasmified by lightining"; break;
-			case dtFalling: DamageText = (GetWorld()->GetTickRandomNumber(10) % 2 == 0) ? "fell to death" : "hit the ground too hard"; break;
+			case dtFalling: DamageText = GetRandomProvider().RandBool() ? "fell to death" : "hit the ground too hard"; break;
 			case dtDrowning: DamageText = "drowned"; break;
-			case dtSuffocating: DamageText = (GetWorld()->GetTickRandomNumber(10) % 2 == 0) ? "git merge'd into a block" : "fused with a block"; break;
+			case dtSuffocating: DamageText = GetRandomProvider().RandBool() ? "git merge'd into a block" : "fused with a block"; break;
 			case dtStarving: DamageText = "forgot the importance of food"; break;
 			case dtCactusContact: DamageText = "was impaled on a cactus"; break;
 			case dtLavaContact: DamageText = "was melted by lava"; break;
@@ -2295,18 +2295,17 @@ void cPlayer::UseEquippedItem(int a_Amount)
 	int UnbreakingLevel = static_cast<int>(Item.m_Enchantments.GetLevel(cEnchantments::enchUnbreaking));
 	if (UnbreakingLevel > 0)
 	{
-		int chance;
+		double chance = 0.0;
 		if (ItemCategory::IsArmor(Item.m_ItemType))
 		{
-			chance = 60 + (40 / (UnbreakingLevel + 1));
+			chance = 0.6 + (0.4 / (UnbreakingLevel + 1));
 		}
 		else
 		{
-			chance = 100 / (UnbreakingLevel + 1);
+			chance = 1.0 / (UnbreakingLevel + 1);
 		}
 
-		cFastRandom Random;
+		if (GetRandomProvider().RandBool(chance))
-		if (Random.NextInt(101) <= chance)
 		{
 			return;
 		}

src/Entities/ThrownEggEntity.cpp

@@ -74,11 +74,12 @@ void cThrownEggEntity::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 
 void cThrownEggEntity::TrySpawnChicken(const Vector3d & a_HitPos)
 {
-	if (m_World->GetTickRandomNumber(7) == 1)
+	auto & Random = GetRandomProvider();
+	if (Random.RandBool(0.125))
 	{
 		m_World->SpawnMob(a_HitPos.x, a_HitPos.y, a_HitPos.z, mtChicken, true);
 	}
-	else if (m_World->GetTickRandomNumber(32) == 1)
+	else if (Random.RandBool(1.0 / 33.0))
 	{
 		m_World->SpawnMob(a_HitPos.x, a_HitPos.y, a_HitPos.z, mtChicken, true);
 		m_World->SpawnMob(a_HitPos.x, a_HitPos.y, a_HitPos.z, mtChicken, true);

src/FastRandom.cpp

@@ -1,11 +1,11 @@
 
 // FastRandom.cpp
 
-// Implements the cFastRandom class representing a fast random number generator
 
 #include "Globals.h"
 #include "FastRandom.h"
 
+#include <mutex>
 #include <random>
 
 #if defined (__GNUC__)
@@ -13,109 +13,50 @@
 #elif defined (_MSC_VER)
 	#define ATTRIBUTE_TLS static __declspec(thread)
 #else
-	#error "Unknown thread local storage qualifier"
+	#define ATTRIBUTE_TLS thread_local
 #endif
 
-static unsigned int GetRandomSeed()
+
+
+
+
+MTRand & GetRandomProvider()
 {
-	ATTRIBUTE_TLS bool SeedCounterInitialized = 0;
+	// Some compilers don't support thread_local for non-POD types, this is purely a work around for that restriction.
-	ATTRIBUTE_TLS unsigned int SeedCounter = 0;
+	// There should be minimal overhead for the non-initializing case and all thread's instances are deleted properly.
+	ATTRIBUTE_TLS MTRand * LocalPtr = nullptr;
+	if (LocalPtr == nullptr)
+	{
+		// This list allows deletion of elements as if they had static storage duration
+		static std::mutex CSDeleteList;
+		static std::list<std::unique_ptr<MTRand>> DeleteList;
+
+		cRandomDeviceSeeder seeder;
+		auto NewInstance = cpp14::make_unique<MTRand>(seeder);
+		auto TempPtr = NewInstance.get();
+
+		std::lock_guard<std::mutex> Lock(CSDeleteList);
+		DeleteList.push_front(std::move(NewInstance));
+		LocalPtr = TempPtr;  // Set after push_back so LocalPtr won't dangle if it throws
+	}
+	return *LocalPtr;
+}
+
+
+
+
+
+UInt32 Detail::GetRandomSeed()
+{
+	ATTRIBUTE_TLS bool SeedCounterInitialized = false;
+	ATTRIBUTE_TLS UInt32 SeedCounter = 0;
 
 	if (!SeedCounterInitialized)
 	{
 		std::random_device rd;
-		std::uniform_int_distribution<unsigned int> dist;
+		std::uniform_int_distribution<UInt32> dist;
 		SeedCounter = dist(rd);
 		SeedCounterInitialized = true;
 	}
 	return ++SeedCounter;
 }
-
-
-
-
-////////////////////////////////////////////////////////////////////////////////
-// cFastRandom:
-
-
-
-
-
-cFastRandom::cFastRandom(void) :
-	m_LinearRand(GetRandomSeed())
-{
-}
-
-
-
-
-
-int cFastRandom::NextInt(int a_Range)
-{
-	std::uniform_int_distribution<> distribution(0, a_Range - 1);
-	return distribution(m_LinearRand);
-}
-
-
-
-
-
-
-float cFastRandom::NextFloat(float a_Range)
-{
-	std::uniform_real_distribution<float> distribution(0, a_Range);
-	return distribution(m_LinearRand);
-}
-
-
-
-
-
-
-int cFastRandom::GenerateRandomInteger(int a_Begin, int a_End)
-{
-	std::uniform_int_distribution<> distribution(a_Begin, a_End);
-	return distribution(m_LinearRand);
-}
-
-
-
-
-
-////////////////////////////////////////////////////////////////////////////////
-// MTRand:
-
-MTRand::MTRand() :
-	m_MersenneRand(GetRandomSeed())
-{
-}
-
-
-
-
-
-int MTRand::randInt(int a_Range)
-{
-	std::uniform_int_distribution<> distribution(0, a_Range);
-	return distribution(m_MersenneRand);
-}
-
-
-
-
-
-int MTRand::randInt()
-{
-	std::uniform_int_distribution<> distribution(0, std::numeric_limits<int>::max());
-	return distribution(m_MersenneRand);
-}
-
-
-
-
-
-double MTRand::rand(double a_Range)
-{
-	std::uniform_real_distribution<> distribution(0, a_Range);
-	return distribution(m_MersenneRand);
-}

src/FastRandom.h

@@ -4,17 +4,10 @@
 // Declares the cFastRandom class representing a fast random number generator
 
 /*
-The cFastRandom aims to provide a very fast, although not very cryptographically secure, random generator.
+The cFastRandom alias should be avoided in favor of the result of a call to GetRandomProvider().
-It is fast to instantiate, fast to query next, and partially multi-thread-safe.
+The MTRand generator used is faster, has a better range and provides higher quality randomness.
-It is multi-thread-safe in the sense that it can be accessed from multiple threads without crashing, but it may
+Note that MTRand is relatively costly to construct and so instances should be long lived,
-yield duplicate numbers in that case.
+prefer calls to GetRandomProvider over creating new instances.
-
-Internally, this works similar to cNoise's integral noise generation, with some predefined inputs: the seed is
-taken from a global counter and the random is calculated using a counter that is incremented on each use (hence
-the multi-thread duplication). Two alternatives exists for each function, one that takes a range parameter,
-and another that takes an additional "salt" parameter; this salt is used as an additional input to the random,
-in order to avoid multi-thread duplication. If two threads both use the class at the same time with different
-salts, the values they get will be different.
 */
 
 
@@ -23,58 +16,195 @@ salts, the values they get will be different.
 
 #pragma once
 #include <random>
+#include <type_traits>
+#include <limits>
 
 
 
 
 
-class cFastRandom
+namespace Detail
+{
+	/** Returns a low quality seed. */
+	UInt32 GetRandomSeed();
+
+	/** Aliases true_type if Char is any variant of char ignoring signed-ness. */
+	template <class Char>
+	using IsChar = typename std::is_same<typename std::make_signed<Char>::type, signed char>::type;
+
+	template <class IntType>
+	struct cUniformImpl :
+		public std::conditional<
+			IsChar<IntType>::value,
+			typename std::conditional<  // Match signed-ness of IntType
+				std::is_signed<IntType>::value,
+				std::uniform_int_distribution<short>,
+				std::uniform_int_distribution<unsigned short>
+			>::type,
+			std::uniform_int_distribution<IntType>
+		>
+	{
+	};
+
+	/** uniform_int_distribution<char> is undefined so this aliases a valid type. */
+	template <class IntType>
+	using cUniform = typename cUniformImpl<IntType>::type;
+}
+
+
+
+
+
+/** Class to wrap any random engine to provide a more convenient interface. */
+template <class RandomEngine>
+class cRandomWrapper
 {
 public:
+	/** Initialize with a low quality seed. */
+	cRandomWrapper():
+		m_Engine(Detail::GetRandomSeed())
+	{
+	}
 
-	cFastRandom(void);
 
-	/** Returns a random int in the range [0 .. a_Range - 1]; a_Range must be less than 1M */
+	/** Initialize with a SeedSequence. */
-	int NextInt(int a_Range);
+	template <class SeedSeq>
+	cRandomWrapper(SeedSeq & a_SeedSeq):
+		m_Engine(a_SeedSeq)
+	{
+	}
 
-	/** Returns a random float in the range [0 .. a_Range]; a_Range must be less than 1M */
-	float NextFloat(float a_Range);
 
-	/** Returns a random float between 0 and 1. */
-	float NextFloat(void) { return NextFloat(1); }
 
-	/** Returns a random int in the range [a_Begin .. a_End] */
+	/** Return a random IntType in the range [a_Min, a_Max]. */
-	int GenerateRandomInteger(int a_Begin, int a_End);
+	template <class IntType = int, class ArgType>
+	IntType RandInt(ArgType a_Min, ArgType a_Max)
+	{
+		ASSERT(
+			(a_Max >= a_Min) &&
+			(a_Max <= std::numeric_limits<IntType>::max()) &&
+			(a_Min >= std::numeric_limits<IntType>::min())
+		);
+		Detail::cUniform<IntType> dist(
+			static_cast<IntType>(a_Min),
+			static_cast<IntType>(a_Max)
+		);
+		return static_cast<IntType>(dist(m_Engine));
+	}
+
+
+
+
+
+	/** Return a random IntType in the range [0, a_Max]. */
+	template <class IntType = int, class ArgType>
+	IntType RandInt(ArgType a_Max)
+	{
+		ASSERT((a_Max >= 0) && (a_Max <= std::numeric_limits<IntType>::max()));
+		Detail::cUniform<IntType> dist(IntType(0), static_cast<IntType>(a_Max));
+		return static_cast<IntType>(dist(m_Engine));
+	}
+
+
+
+
+
+	/** Return a random IntType in the range [0, std::numeric_limits<IntType>::max()]. */
+	template <class IntType = int>
+	IntType RandInt()
+	{
+		Detail::cUniform<IntType> dist(IntType(0), std::numeric_limits<IntType>::max());
+		return static_cast<IntType>(dist(m_Engine));
+	}
+
+
+
+
+
+	/** Return a random RealType in the range [a_Min, a_Max). */
+	template <class RealType = float, class ArgType>
+	RealType RandReal(ArgType a_Min, ArgType a_Max)
+	{
+		std::uniform_real_distribution<RealType> dist(a_Min, a_Max);
+		return dist(m_Engine);
+	}
+
+
+
+
+
+	/** Return a random RealType in the range [0, a_Max). */
+	template <class RealType = float, class ArgType>
+	RealType RandReal(ArgType a_Max)
+	{
+		std::uniform_real_distribution<RealType> dist(RealType(0), a_Max);
+		return dist(m_Engine);
+	}
+
+
+
+
+
+	/** Return a random RealType in the range [0, 1). */
+	template <class RealType = float>
+	RealType RandReal()
+	{
+		std::uniform_real_distribution<RealType> dist;
+		return dist(m_Engine);
+	}
+
+
+
+
+
+	/** Return a random bool with the given probability of being true. */
+	bool RandBool(double a_TrueProbability = 0.5)
+	{
+		std::bernoulli_distribution dist(a_TrueProbability);
+		return dist(m_Engine);
+	}
+
+
+
+
+	/** Returns a reference to the underlying random engine. */
+	RandomEngine & Engine()
+	{
+		return m_Engine;
+	}
 
 private:
 
-	std::minstd_rand m_LinearRand;
+	RandomEngine m_Engine;
 };
 
 
 
 
 
-class MTRand
+/** Utility to seed a random engine with maximal entropy from random_device. */
+struct cRandomDeviceSeeder
 {
-public:
+	using result_type = std::random_device::result_type;
 
-	MTRand(void);
+	template <class Itr>
-
+	void generate(Itr first, Itr last)
-	/** Returns a random integer in the range [0 .. a_Range]. */
+	{
-	int randInt(int a_Range);
+		std::random_device rd;
-
+		std::uniform_int_distribution<result_type> dist;
-	/** Returns a random integer in the range [0 .. MAX_INT]. */
+		for (; first != last; ++first)
-	int randInt(void);
+		{
-
+			*first = dist(rd);
-	/** Returns a random floating point number in the range [0 .. a_Range]. */
+		}
-	double rand(double a_Range);
+	}
-
-private:
-
-	std::mt19937 m_MersenneRand;
 };
 
 
 
 
+
+using cFastRandom = cRandomWrapper<std::minstd_rand>;
+using MTRand = cRandomWrapper<std::mt19937>;
+
+/** Returns the current thread's random number source. */
+MTRand & GetRandomProvider();

src/Generating/ChunkGenerator.cpp

@@ -59,8 +59,7 @@ bool cChunkGenerator::Start(cPluginInterface & a_PluginInterface, cChunkSink & a
 	}
 	else
 	{
-		MTRand rnd;
+		m_Seed = GetRandomProvider().RandInt();
-		m_Seed = rnd.randInt();
 		LOGINFO("Chosen a new random seed for world: %d", m_Seed);
 		a_IniFile.SetValueI("Seed", "Seed", m_Seed);
 	}

src/Generating/DungeonRoomsFinisher.cpp

@@ -162,7 +162,7 @@ protected:
 		int RelStartZ = Clamp(a_StartZ - BlockZ, 0, cChunkDef::Width - 1);
 		int RelEndX   = Clamp(a_EndX - BlockX,   0, cChunkDef::Width);
 		int RelEndZ   = Clamp(a_EndZ - BlockZ,   0, cChunkDef::Width);
-		cFastRandom rnd;
+		auto & rnd = GetRandomProvider();
 		for (int y = a_StartY; y < a_EndY; y++)
 		{
 			for (int z = RelStartZ; z < RelEndZ; z++)
@@ -171,7 +171,7 @@ protected:
 				{
 					if (cBlockInfo::CanBeTerraformed(a_ChunkDesc.GetBlockType(x, y, z)))
 					{
-						BLOCKTYPE BlockType = (rnd.NextInt(101) < 75) ? a_DstBlockType1 : a_DstBlockType2;
+						BLOCKTYPE BlockType = rnd.RandBool(0.75) ? a_DstBlockType1 : a_DstBlockType2;
 						a_ChunkDesc.SetBlockType(x, y, z, BlockType);
 					}
 				}  // for x

src/Item.cpp

@@ -332,9 +332,9 @@ bool cItem::EnchantByXPLevels(int a_NumXPLevels)
 		return false;
 	}
 
-	cFastRandom Random;
+	auto & Random = GetRandomProvider();
-	int ModifiedEnchantmentLevel = a_NumXPLevels + static_cast<int>(Random.NextFloat(static_cast<float>(Enchantability / 4))) + static_cast<int>(Random.NextFloat(static_cast<float>(Enchantability / 4))) + 1;
+	int ModifiedEnchantmentLevel = a_NumXPLevels + Random.RandInt(Enchantability / 4) + Random.RandInt(Enchantability / 4) + 1;
-	float RandomBonus = 1.0F + (Random.NextFloat(1) + Random.NextFloat(1) - 1.0F) * 0.15F;
+	float RandomBonus = 1.0F + (Random.RandReal() + Random.RandReal() - 1.0F) * 0.15F;
 	int FinalEnchantmentLevel = static_cast<int>(ModifiedEnchantmentLevel * RandomBonus + 0.5F);
 
 	cWeightedEnchantments Enchantments;
@@ -352,12 +352,10 @@ bool cItem::EnchantByXPLevels(int a_NumXPLevels)
 	// Checking for conflicting enchantments
 	cEnchantments::CheckEnchantmentConflictsFromVector(Enchantments, Enchantment1);
 
-	float NewEnchantmentLevel = static_cast<float>(a_NumXPLevels);
-
 	// Next Enchantment (Second)
-	NewEnchantmentLevel = NewEnchantmentLevel / 2;
+	float NewEnchantmentLevel = a_NumXPLevels / 2.0f;
-	float SecondEnchantmentChance = (NewEnchantmentLevel + 1) / 50 * 100;
+	float SecondEnchantmentChance = (NewEnchantmentLevel + 1) / 50.0f;
-	if (Enchantments.empty() || (Random.NextFloat(100) > SecondEnchantmentChance))
+	if (Enchantments.empty() || !Random.RandBool(SecondEnchantmentChance))
 	{
 		return true;
 	}
@@ -370,9 +368,9 @@ bool cItem::EnchantByXPLevels(int a_NumXPLevels)
 	cEnchantments::CheckEnchantmentConflictsFromVector(Enchantments, Enchantment2);
 
 	// Next Enchantment (Third)
-	NewEnchantmentLevel = NewEnchantmentLevel / 2;
+	NewEnchantmentLevel = NewEnchantmentLevel / 2.0f;
-	float ThirdEnchantmentChance = (NewEnchantmentLevel + 1) / 50 * 100;
+	float ThirdEnchantmentChance = (NewEnchantmentLevel + 1) / 50.0f;
-	if (Enchantments.empty() || (Random.NextFloat(100) > ThirdEnchantmentChance))
+	if (Enchantments.empty() || !Random.RandBool(ThirdEnchantmentChance))
 	{
 		return true;
 	}
@@ -385,9 +383,9 @@ bool cItem::EnchantByXPLevels(int a_NumXPLevels)
 	cEnchantments::CheckEnchantmentConflictsFromVector(Enchantments, Enchantment3);
 
 	// Next Enchantment (Fourth)
-	NewEnchantmentLevel = NewEnchantmentLevel / 2;
+	NewEnchantmentLevel = NewEnchantmentLevel / 2.0f;
-	float FourthEnchantmentChance = (NewEnchantmentLevel + 1) / 50 * 100;
+	float FourthEnchantmentChance = (NewEnchantmentLevel + 1) / 50.0f;
-	if (Enchantments.empty() || (Random.NextFloat(100) > FourthEnchantmentChance))
+	if (Enchantments.empty() || !Random.RandBool(FourthEnchantmentChance))
 	{
 		return true;
 	}

src/Items/ItemFishingRod.h

@@ -108,6 +108,8 @@ public:
 			return false;
 		}
 
+		auto & Random = GetRandomProvider();
+
 		if (a_Player->IsFishing())
 		{
 			cFloaterCallback FloaterInfo;
@@ -122,10 +124,10 @@ public:
 			else if (FloaterInfo.CanPickup())
 			{
 				cItems Drops;
-				int ItemCategory = a_World->GetTickRandomNumber(99);
+				int ItemCategory = Random.RandInt(99);
 				if (ItemCategory <= 4)  // Treasures 5%
 				{
-					int Treasure = a_World->GetTickRandomNumber(5);
+					int Treasure = Random.RandInt(5);
 					switch (Treasure)
 					{
 						case 0:
@@ -140,7 +142,7 @@ public:
 						}
 						case 2:
 						{
-							Drops.Add(cItem(E_ITEM_FISHING_ROD, 1, static_cast<short>(a_World->GetTickRandomNumber(50))));  // Fishing rod with durability. TODO: Enchantments on it
+							Drops.Add(cItem(E_ITEM_FISHING_ROD, 1, Random.RandInt<short>(50)));  // Fishing rod with durability. TODO: Enchantments on it
 							break;
 						}
 						case 3:
@@ -164,14 +166,14 @@ public:
 				}
 				else if (ItemCategory <= 14)  // Junk 10%
 				{
-					int Junk = a_World->GetTickRandomNumber(70);
+					int Junk = Random.RandInt(70);
 					if (Junk <= 1)
 					{
 						Drops.Add(cItem(E_ITEM_DYE, 10, 0));
 					}
 					else if (Junk <= 4)
 					{
-						Drops.Add(cItem(E_ITEM_BOW, 1, static_cast<short>(a_World->GetTickRandomNumber(64))));
+						Drops.Add(cItem(E_ITEM_BOW, 1, Random.RandInt<short>(64)));
 					}
 					else if (Junk <= 9)
 					{
@@ -214,7 +216,7 @@ public:
 				}
 				else  // Fish
 				{
-					int FishType = a_World->GetTickRandomNumber(99);
+					int FishType = Random.RandInt(99);
 					if (FishType <= 1)  // Clownfish has a 2% chance of spawning
 					{
 						Drops.Add(cItem(E_ITEM_RAW_FISH, 1, E_META_RAW_FISH_CLOWNFISH));
@@ -250,7 +252,7 @@ public:
 		}
 		else
 		{
-			cFloater * Floater = new cFloater(a_Player->GetPosX(), a_Player->GetStance(), a_Player->GetPosZ(), a_Player->GetLookVector() * 15, a_Player->GetUniqueID(), static_cast<int>(100 + static_cast<unsigned int>(a_World->GetTickRandomNumber(800)) - (a_Player->GetEquippedItem().m_Enchantments.GetLevel(cEnchantments::enchLure) * 100)));
+			cFloater * Floater = new cFloater(a_Player->GetPosX(), a_Player->GetStance(), a_Player->GetPosZ(), a_Player->GetLookVector() * 15, a_Player->GetUniqueID(), (Random.RandInt(100, 900) - static_cast<int>(a_Player->GetEquippedItem().m_Enchantments.GetLevel(cEnchantments::enchLure) * 100)));
 			if (!Floater->Initialize(*a_World))
 			{
 				delete Floater;

src/Items/ItemHandler.cpp

@@ -861,8 +861,7 @@ bool cItemHandler::EatItem(cPlayer * a_Player, cItem * a_Item)
 		float Chance;
 		if (Success && GetEatEffect(EffectType, EffectDurationTicks, EffectIntensity, Chance))
 		{
-			cFastRandom r1;
+			if (GetRandomProvider().RandBool(Chance))
-			if (r1.NextFloat() < Chance)
 			{
 				a_Player->AddEntityEffect(EffectType, EffectDurationTicks, EffectIntensity, Chance);
 			}

src/Items/ItemThrowable.h

@@ -36,8 +36,7 @@ public:
 		Vector3d Speed = a_Player->GetLookVector() * m_SpeedCoeff;
 
 		// Play sound
-		cFastRandom Random;
+		a_World->BroadcastSoundEffect("entity.arrow.shoot", a_Player->GetPosX(), a_Player->GetPosY() - a_Player->GetHeight(), a_Player->GetPosZ(), 0.5f, 0.4f / GetRandomProvider().RandReal(0.8f, 1.2f));
-		a_World->BroadcastSoundEffect("entity.arrow.shoot", a_Player->GetPosX(), a_Player->GetPosY() - a_Player->GetHeight(), a_Player->GetPosZ(), 0.5f, 0.4f / (Random.NextFloat(1.0f) * 0.4f + 0.8f));
 
 		if (a_World->CreateProjectile(Pos.x, Pos.y, Pos.z, m_ProjectileKind, a_Player, &a_Player->GetEquippedItem(), &Speed) == cEntity::INVALID_ID)
 		{

src/Map.cpp

@@ -306,10 +306,8 @@ const cMapDecorator cMap::CreateDecorator(const cEntity * a_TrackedEntity)
 
 		if (GetDimension() == dimNether)
 		{
-			cFastRandom Random;
-
 			// TODO 2014-02-19 xdot: Refine
-			Rot = Random.NextInt(16);
+			Rot = GetRandomProvider().RandInt(15);
 		}
 		else
 		{

src/MobSpawner.cpp

@@ -111,12 +111,8 @@ eMonsterType cMobSpawner::ChooseMobType(EMCSBiome a_Biome)
 	if (allowedMobsSize > 0)
 	{
 		std::set<eMonsterType>::iterator itr = allowedMobs.begin();
-		int iRandom = m_Random.NextInt(static_cast<int>(allowedMobsSize));
 
-		for (int i = 0; i < iRandom; i++)
+		std::advance(itr, GetRandomProvider().RandInt<size_t>(allowedMobsSize - 1));
-		{
-			++itr;
-		}
 
 		return *itr;
 	}
@@ -139,7 +135,7 @@ bool cMobSpawner::CanSpawnHere(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_R
 		return false;   // Make sure mobs do not spawn on bedrock.
 	}
 
-	cFastRandom Random;
+	auto & Random = GetRandomProvider();
 	BLOCKTYPE TargetBlock = a_Chunk->GetBlock(a_RelX, a_RelY, a_RelZ);
 
 	cPlayer * a_Closest_Player = a_Chunk->GetWorld()->FindClosestPlayer(a_Chunk->PositionToWorldPosition(a_RelX, a_RelY, a_RelZ), 24);
@@ -202,7 +198,7 @@ bool cMobSpawner::CanSpawnHere(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_R
 					(BlockBelow == E_BLOCK_GRASS) || (BlockBelow == E_BLOCK_LEAVES) || (BlockBelow == E_BLOCK_NEW_LEAVES)
 				) &&
 				(a_RelY >= 62) &&
-				(Random.NextInt(3) != 0)
+				(Random.RandBool(2.0 / 3.0))
 			);
 		}
 
@@ -260,7 +256,7 @@ bool cMobSpawner::CanSpawnHere(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_R
 				(!cBlockInfo::IsTransparent(BlockBelow)) &&
 				(SkyLight <= 7) &&
 				(BlockLight <= 7) &&
-				(Random.NextInt(2) == 0)
+				(Random.RandBool())
 			);
 		}
 
@@ -274,7 +270,7 @@ bool cMobSpawner::CanSpawnHere(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_R
 				(!cBlockInfo::IsTransparent(BlockBelow)) &&
 				(SkyLight <= 7) &&
 				(BlockLight <= 7) &&
-				(Random.NextInt(2) == 0)
+				(Random.RandBool())
 			);
 		}
 
@@ -298,7 +294,7 @@ bool cMobSpawner::CanSpawnHere(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_R
 				(TargetBlock == E_BLOCK_AIR) &&
 				(BlockAbove == E_BLOCK_AIR) &&
 				(!cBlockInfo::IsTransparent(BlockBelow)) &&
-				(Random.NextInt(20) == 0)
+				(Random.RandBool(0.05))
 			);
 		}
 

src/MobSpawner.h

@@ -5,7 +5,6 @@
 #include "BlockID.h"
 #include "ChunkDef.h"
 #include "Chunk.h"
-#include "FastRandom.h"
 #include "Mobs/Monster.h"  // This is a side-effect of keeping Mobfamily inside Monster class. I'd prefer to keep both (Mobfamily and Monster) inside a "Monster" namespace MG TODO : do it
 
 
@@ -66,7 +65,6 @@ protected :
 	bool m_NewPack;
 	eMonsterType m_MobType;
 	std::set<cMonster*> m_Spawned;
-	cFastRandom m_Random;
 } ;
 
 

src/Mobs/Chicken.cpp

@@ -34,7 +34,7 @@ void cChicken::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 		return;  // Babies don't lay eggs
 	}
 
-	if ((m_EggDropTimer == 6000) && (m_World->GetTickRandomNumber(1) == 0))
+	if ((m_EggDropTimer == 6000) && GetRandomProvider().RandBool())
 	{
 		cItems Drops;
 		m_EggDropTimer = 0;

src/Mobs/Horse.cpp

@@ -41,16 +41,18 @@ void cHorse::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 		return;
 	}
 
+	auto & Random = GetRandomProvider();
+
 	if (!m_bIsMouthOpen)
 	{
-		if (m_World->GetTickRandomNumber(50) == 25)
+		if (Random.RandBool(0.02))
 		{
 			m_bIsMouthOpen = true;
 		}
 	}
 	else
 	{
-		if (m_World->GetTickRandomNumber(10) == 5)
+		if (Random.RandBool(0.10))
 		{
 			m_bIsMouthOpen = false;
 		}
@@ -60,7 +62,7 @@ void cHorse::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 	{
 		if (m_TameAttemptTimes < m_TimesToTame)
 		{
-			if (m_World->GetTickRandomNumber(50) == 25)
+			if (Random.RandBool(0.02))
 			{
 				m_World->BroadcastSoundParticleEffect(EffectID::PARTICLE_SMOKE, FloorC(GetPosX()), FloorC(GetPosY()), FloorC(GetPosZ()), int(SmokeDirection::SOUTH_EAST));
 				m_World->BroadcastSoundParticleEffect(EffectID::PARTICLE_SMOKE, FloorC(GetPosX()), FloorC(GetPosY()), FloorC(GetPosZ()), int(SmokeDirection::SOUTH_WEST));

src/Mobs/Monster.cpp

@@ -512,7 +512,7 @@ void cMonster::KilledBy(TakeDamageInfo & a_TDI)
 		case mtOcelot:
 		case mtWolf:
 		{
-			Reward = m_World->GetTickRandomNumber(2) + 1;
+			Reward = GetRandomProvider().RandInt(1, 3);
 			break;
 		}
 
@@ -531,7 +531,7 @@ void cMonster::KilledBy(TakeDamageInfo & a_TDI)
 		case mtSlime:
 		case mtMagmaCube:
 		{
-			Reward = 6 + (m_World->GetTickRandomNumber(2));
+			Reward = GetRandomProvider().RandInt(6, 8);
 			break;
 		}
 		case mtBlaze:
@@ -657,13 +657,15 @@ void cMonster::InStateIdle(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 
 	if (m_IdleInterval > std::chrono::seconds(1))
 	{
+		auto & Random = GetRandomProvider();
+
 		// At this interval the results are predictable
-		int rem = m_World->GetTickRandomNumber(6) + 1;
+		int rem = Random.RandInt(1, 7);
 		m_IdleInterval -= std::chrono::seconds(1);  // So nothing gets dropped when the server hangs for a few seconds
 
 		Vector3d Dist;
-		Dist.x = static_cast<double>(m_World->GetTickRandomNumber(10)) - 5.0;
+		Dist.x = static_cast<double>(Random.RandInt(-5, 5));
-		Dist.z = static_cast<double>(m_World->GetTickRandomNumber(10)) - 5.0;
+		Dist.z = static_cast<double>(Random.RandInt(-5, 5));
 
 		if ((Dist.SqrLength() > 2)  && (rem >= 3))
 		{
@@ -1005,7 +1007,7 @@ cPawn * cMonster::GetTarget ()
 
 cMonster * cMonster::NewMonsterFromType(eMonsterType a_MobType)
 {
-	cFastRandom Random;
+	auto & Random = GetRandomProvider();
 	cMonster * toReturn = nullptr;
 
 	// Create the mob entity
@@ -1013,23 +1015,23 @@ cMonster * cMonster::NewMonsterFromType(eMonsterType a_MobType)
 	{
 		case mtMagmaCube:
 		{
-			toReturn = new cMagmaCube(1 << Random.NextInt(3));  // Size 1, 2 or 4
+			toReturn = new cMagmaCube(1 << Random.RandInt(2));  // Size 1, 2 or 4
 			break;
 		}
 		case mtSlime:
 		{
-			toReturn = new cSlime(1 << Random.NextInt(3));  // Size 1, 2 or 4
+			toReturn = new cSlime(1 << Random.RandInt(2));  // Size 1, 2 or 4
 			break;
 		}
 		case mtSkeleton:
 		{
 			// TODO: Actual detection of spawning in Nether
-			toReturn = new cSkeleton((Random.NextInt(1) == 0) ? false : true);
+			toReturn = new cSkeleton(false);
 			break;
 		}
 		case mtVillager:
 		{
-			int VillagerType = Random.NextInt(6);
+			int VillagerType = Random.RandInt(6);
 			if (VillagerType == 6)
 			{
 				// Give farmers a better chance of spawning
@@ -1042,10 +1044,10 @@ cMonster * cMonster::NewMonsterFromType(eMonsterType a_MobType)
 		case mtHorse:
 		{
 			// Horses take a type (species), a colour, and a style (dots, stripes, etc.)
-			int HorseType = Random.NextInt(8);
+			int HorseType = Random.RandInt(7);
-			int HorseColor = Random.NextInt(7);
+			int HorseColor = Random.RandInt(6);
-			int HorseStyle = Random.NextInt(5);
+			int HorseStyle = Random.RandInt(4);
-			int HorseTameTimes = Random.NextInt(6) + 1;
+			int HorseTameTimes = Random.RandInt(1, 6);
 
 			if ((HorseType == 5) || (HorseType == 6) || (HorseType == 7))
 			{
@@ -1097,11 +1099,10 @@ cMonster * cMonster::NewMonsterFromType(eMonsterType a_MobType)
 
 void cMonster::AddRandomDropItem(cItems & a_Drops, unsigned int a_Min, unsigned int a_Max, short a_Item, short a_ItemHealth)
 {
-	MTRand r1;
+	auto Count = GetRandomProvider().RandInt<char>(static_cast<char>(a_Min), static_cast<char>(a_Max));
-	int Count = static_cast<int>(static_cast<unsigned int>(r1.randInt()) % (a_Max + 1 - a_Min) + a_Min);
 	if (Count > 0)
 	{
-		a_Drops.push_back(cItem(a_Item, static_cast<char>(Count), a_ItemHealth));
+		a_Drops.emplace_back(a_Item, Count, a_ItemHealth);
 	}
 }
 
@@ -1111,9 +1112,7 @@ void cMonster::AddRandomDropItem(cItems & a_Drops, unsigned int a_Min, unsigned
 
 void cMonster::AddRandomUncommonDropItem(cItems & a_Drops, float a_Chance, short a_Item, short a_ItemHealth)
 {
-	MTRand r1;
+	if (GetRandomProvider().RandBool(a_Chance / 100.0))
-	int Count = r1.randInt() % 1000;
-	if (Count < (a_Chance * 10))
 	{
 		a_Drops.push_back(cItem(a_Item, 1, a_ItemHealth));
 	}
@@ -1125,11 +1124,10 @@ void cMonster::AddRandomUncommonDropItem(cItems & a_Drops, float a_Chance, short
 
 void cMonster::AddRandomRareDropItem(cItems & a_Drops, cItems & a_Items, unsigned int a_LootingLevel)
 {
-	MTRand r1;
+	auto & r1 = GetRandomProvider();
-	unsigned int Count = static_cast<unsigned int>(static_cast<unsigned long>(r1.randInt()) % 200);
+	if (r1.RandBool((5 + a_LootingLevel) / 200.0))
-	if (Count < (5 + a_LootingLevel))
 	{
-		size_t Rare = static_cast<size_t>(r1.randInt()) % a_Items.Size();
+		size_t Rare = r1.RandInt<size_t>(a_Items.Size() - 1);
 		a_Drops.push_back(a_Items.at(Rare));
 	}
 }
@@ -1140,8 +1138,11 @@ void cMonster::AddRandomRareDropItem(cItems & a_Drops, cItems & a_Items, unsigne
 
 void cMonster::AddRandomArmorDropItem(cItems & a_Drops, unsigned int a_LootingLevel)
 {
-	MTRand r1;
+	auto & r1 = GetRandomProvider();
-	if (r1.randInt() % 200 < ((m_DropChanceHelmet * 200) + (a_LootingLevel * 2)))
+
+	double LootingBonus = a_LootingLevel / 100.0;
+
+	if (r1.RandBool(m_DropChanceHelmet + LootingBonus))
 	{
 		if (!GetEquippedHelmet().IsEmpty())
 		{
@@ -1149,7 +1150,7 @@ void cMonster::AddRandomArmorDropItem(cItems & a_Drops, unsigned int a_LootingLe
 		}
 	}
 
-	if (r1.randInt() % 200 < ((m_DropChanceChestplate * 200) + (a_LootingLevel * 2)))
+	if (r1.RandBool(m_DropChanceChestplate + LootingBonus))
 	{
 		if (!GetEquippedChestplate().IsEmpty())
 		{
@@ -1157,7 +1158,7 @@ void cMonster::AddRandomArmorDropItem(cItems & a_Drops, unsigned int a_LootingLe
 		}
 	}
 
-	if (r1.randInt() % 200 < ((m_DropChanceLeggings * 200) + (a_LootingLevel * 2)))
+	if (r1.RandBool(m_DropChanceLeggings + LootingBonus))
 	{
 		if (!GetEquippedLeggings().IsEmpty())
 		{
@@ -1165,7 +1166,7 @@ void cMonster::AddRandomArmorDropItem(cItems & a_Drops, unsigned int a_LootingLe
 		}
 	}
 
-	if (r1.randInt() % 200 < ((m_DropChanceBoots * 200) + (a_LootingLevel * 2)))
+	if (r1.RandBool(m_DropChanceBoots + LootingBonus))
 	{
 		if (!GetEquippedBoots().IsEmpty())
 		{
@@ -1180,8 +1181,7 @@ void cMonster::AddRandomArmorDropItem(cItems & a_Drops, unsigned int a_LootingLe
 
 void cMonster::AddRandomWeaponDropItem(cItems & a_Drops, unsigned int a_LootingLevel)
 {
-	MTRand r1;
+	if (GetRandomProvider().RandBool(m_DropChanceWeapon + (a_LootingLevel / 100.0)))
-	if (r1.randInt() % 200 < ((m_DropChanceWeapon * 200) + (a_LootingLevel * 2)))
 	{
 		if (!GetEquippedWeapon().IsEmpty())
 		{

src/Mobs/PassiveMonster.cpp

@@ -127,8 +127,7 @@ void cPassiveMonster::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 				Callback.Baby->InheritFromParents(this, m_LovePartner);
 			}
 
-			cFastRandom Random;
+			m_World->SpawnExperienceOrb(Pos.x, Pos.y, Pos.z, GetRandomProvider().RandInt(1, 6));
-			m_World->SpawnExperienceOrb(Pos.x, Pos.y, Pos.z, 1 + Random.NextInt(6));
 
 			m_LovePartner->ResetLoveMode();
 			ResetLoveMode();

src/Mobs/Path.cpp

@@ -148,7 +148,7 @@ bool cPath::StepOnce()
 	// Check if we have a new NearestPoint.
 	if ((m_Destination - CurrentCell->m_Location).Length() < 5)
 	{
-		if (m_Rand.NextInt(4) == 0)
+		if (GetRandomProvider().RandBool(0.25))
 		{
 			m_NearestPointToTarget = CurrentCell;
 		}

src/Mobs/Path.h

@@ -178,7 +178,6 @@ private:
 	double m_HalfWidth;
 	int m_StepsLeft;
 	cPathCell * m_NearestPointToTarget;
-	cFastRandom m_Rand;
 
 	/* Control fields */
 	ePathFinderStatus m_Status;

src/Mobs/Rabbit.cpp

@@ -10,8 +10,8 @@
 
 
 cRabbit::cRabbit(void) :
-	cRabbit(static_cast<eRabbitType>(cFastRandom().NextInt(
+	cRabbit(static_cast<eRabbitType>(GetRandomProvider().RandInt<UInt8>(
-		static_cast<UInt8>(eRabbitType::SaltAndPepper) + 1  // Max possible Rabbit-Type
+		static_cast<UInt8>(eRabbitType::SaltAndPepper)  // Max possible Rabbit-Type
 	)), 0)
 {
 }

src/Mobs/Sheep.cpp

@@ -65,8 +65,8 @@ void cSheep::OnRightClicked(cPlayer & a_Player)
 		a_Player.UseEquippedItem();
 
 		cItems Drops;
-		int NumDrops = m_World->GetTickRandomNumber(2) + 1;
+		char NumDrops = GetRandomProvider().RandInt<char>(1, 3);
-		Drops.push_back(cItem(E_BLOCK_WOOL, static_cast<char>(NumDrops), static_cast<short>(m_WoolColor)));
+		Drops.emplace_back(E_BLOCK_WOOL, NumDrops, static_cast<short>(m_WoolColor));
 		m_World->SpawnItemPickups(Drops, GetPosX(), GetPosY(), GetPosZ(), 10);
 		m_World->BroadcastSoundEffect("entity.sheep.shear", GetPosX(), GetPosY(), GetPosZ(), 1.0f, 1.0f);
 	}
@@ -121,7 +121,7 @@ void cSheep::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 	}
 	else
 	{
-		if (m_World->GetTickRandomNumber(600) == 1)
+		if (GetRandomProvider().RandBool(1.0 / 600.0))
 		{
 			if (m_World->GetBlock(PosX, PosY, PosZ) == E_BLOCK_GRASS)
 			{
@@ -167,8 +167,7 @@ void cSheep::InheritFromParents(cPassiveMonster * a_Parent1, cPassiveMonster * a
 			return;
 		}
 	}
-	cFastRandom Random;
+	SetFurColor(GetRandomProvider().RandBool() ? Parent1->GetFurColor() : Parent2->GetFurColor());
-	SetFurColor((Random.NextInt(100) < 50) ? Parent1->GetFurColor() : Parent2->GetFurColor());
 	m_World->BroadcastEntityMetadata(*this);
 }
 
@@ -178,8 +177,7 @@ void cSheep::InheritFromParents(cPassiveMonster * a_Parent1, cPassiveMonster * a
 
 NIBBLETYPE cSheep::GenerateNaturalRandomColor(void)
 {
-	cFastRandom Random;
+	int Chance = GetRandomProvider().RandInt(100);
-	int Chance = Random.NextInt(101);
 
 	if (Chance <= 81)
 	{

src/Mobs/Skeleton.cpp

@@ -51,12 +51,12 @@ void cSkeleton::GetDrops(cItems & a_Drops, cEntity * a_Killer)
 bool cSkeleton::Attack(std::chrono::milliseconds a_Dt)
 {
 	StopMovingToPosition();  // Todo handle this in a better way, the skeleton does some uneeded recalcs due to inStateChasing
-	cFastRandom Random;
+	auto & Random = GetRandomProvider();
 	if ((GetTarget() != nullptr) && (m_AttackCoolDownTicksLeft == 0))
 	{
-		Vector3d Inaccuracy = Vector3d(Random.NextFloat(0.5) - 0.25, Random.NextFloat(0.5) - 0.25, Random.NextFloat(0.5) - 0.25);
+		Vector3d Inaccuracy = Vector3d(Random.RandReal<double>(-0.25, 0.25), Random.RandReal<double>(-0.25, 0.25), Random.RandReal<double>(-0.25, 0.25));
 		Vector3d Speed = (GetTarget()->GetPosition() + Inaccuracy - GetPosition()) * 5;
-		Speed.y = Speed.y - 1 + Random.NextInt(3);
+		Speed.y += Random.RandInt(-1, 1);
 		cArrowEntity * Arrow = new cArrowEntity(this, GetPosX(), GetPosY() + 1, GetPosZ(), Speed);
 		if (Arrow == nullptr)
 		{

src/Mobs/Slime.cpp

@@ -70,8 +70,8 @@ void cSlime::KilledBy(TakeDamageInfo & a_TDI)
 
 	if (m_Size != 1)
 	{
-		cFastRandom Random;
+		auto & Random = GetRandomProvider();
-		int SpawnAmount = 2 + Random.NextInt(3);
+		int SpawnAmount = Random.RandInt(2, 4);
 
 		for (int i = 0; i < SpawnAmount; ++i)
 		{
@@ -80,7 +80,7 @@ void cSlime::KilledBy(TakeDamageInfo & a_TDI)
 
 			cSlime * NewSlime = new cSlime(m_Size / 2);
 			NewSlime->SetPosition(GetPosX() + AddX, GetPosY() + 0.5, GetPosZ() + AddZ);
-			NewSlime->SetYaw(Random.NextFloat(1.0f) * 360.0f);
+			NewSlime->SetYaw(Random.RandReal(360.0f));
 			m_World->SpawnMobFinalize(NewSlime);
 		}
 	}

src/Mobs/Villager.cpp

@@ -32,7 +32,7 @@ bool cVillager::DoTakeDamage(TakeDamageInfo & a_TDI)
 
 	if ((a_TDI.Attacker != nullptr) && a_TDI.Attacker->IsPlayer())
 	{
-		if (m_World->GetTickRandomNumber(5) == 3)
+		if (GetRandomProvider().RandBool(1.0 / 6.0))
 		{
 			m_World->BroadcastEntityStatus(*this, esVillagerAngry);
 		}
@@ -90,7 +90,7 @@ void cVillager::Tick(std::chrono::milliseconds a_Dt, cChunk & a_Chunk)
 	}
 
 	// Don't always try to do a special action. Each tick has 1% to do a special action.
-	if (m_World->GetTickRandomNumber(99) != 0)
+	if (GetRandomProvider().RandBool(0.99))
 	{
 		return;
 	}
@@ -150,7 +150,7 @@ void cVillager::HandleFarmerPrepareFarmCrops()
 
 			m_VillagerAction = true;
 			m_CropsPos = Vector3i(static_cast<int>(GetPosX()) + X - 5, static_cast<int>(GetPosY()) + Y - 3, static_cast<int>(GetPosZ()) + Z - 5);
-			MoveToPosition(Vector3f(static_cast<float>(m_CropsPos.x + 0.5), static_cast<float>(m_CropsPos.y), static_cast<float>(m_CropsPos.z + 0.5)));
+			MoveToPosition(Vector3d(m_CropsPos.x + 0.5, m_CropsPos.y + 0.0, m_CropsPos.z + 0.5));
 			return;
 		}  // for Y loop.
 	}  // Repeat the procces 5 times.

src/Mobs/Witch.cpp

@@ -24,11 +24,11 @@ void cWitch::GetDrops(cItems & a_Drops, cEntity * a_Killer)
 	{
 		LootingLevel = a_Killer->GetEquippedWeapon().m_Enchantments.GetLevel(cEnchantments::enchLooting);
 	}
-	MTRand r1;
+	auto & r1 = GetRandomProvider();
-	int DropTypeCount = (r1.randInt() % 3) + 1;
+	int DropTypeCount = r1.RandInt(1, 3);
 	for (int i = 0; i < DropTypeCount; i++)
 	{
-		int DropType = r1.randInt() % 7;
+		int DropType = r1.RandInt(6);
 		switch (DropType)
 		{
 			case 0: AddRandomDropItem(a_Drops, 0, 2 + LootingLevel, E_ITEM_GLASS_BOTTLE); break;

src/Mobs/Wolf.cpp

@@ -138,7 +138,7 @@ void cWolf::ReceiveNearbyFightInfo(AString a_PlayerID, cPawn * a_Opponent, bool
 		// If a player is asking for help and we already have a target,
 		// there's a 50% chance of helping and a 50% chance of doing nothing
 		// This helps spread a wolf pack's targets over several mobs
-		else if (m_World->GetTickRandomNumber(9)> 4)
+		else if (GetRandomProvider().RandBool())
 		{
 			return;
 		}
@@ -179,7 +179,7 @@ void cWolf::OnRightClicked(cPlayer & a_Player)
 				a_Player.GetInventory().RemoveOneEquippedItem();
 			}
 
-			if (m_World->GetTickRandomNumber(7) == 0)
+			if (GetRandomProvider().RandBool(0.125))
 			{
 				// Taming succeeded
 				SetMaxHealth(20);

src/ProbabDistrib.cpp

@@ -100,8 +100,7 @@ bool cProbabDistrib::SetDefString(const AString & a_DefString)
 
 int cProbabDistrib::Random(MTRand & a_Rand) const
 {
-	int v = a_Rand.randInt(m_Sum);
+	return MapValue(a_Rand.RandInt(m_Sum));
-	return MapValue(v);
 }
 
 

src/ProbabDistrib.h

@@ -20,8 +20,7 @@ Usage:
 
 
 
-// fwd:
+#include "FastRandom.h"
-class MTRand;
 
 
 

src/Server.cpp

@@ -17,6 +17,7 @@
 #include "WebAdmin.h"
 #include "Protocol/ProtocolRecognizer.h"
 #include "CommandOutput.h"
+#include "FastRandom.h"
 
 #include "IniFile.h"
 #include "Vector3.h"
@@ -218,9 +219,9 @@ bool cServer::InitServer(cSettingsRepositoryInterface & a_Settings, bool a_Shoul
 	m_ShouldAuthenticate = a_ShouldAuth;
 	if (m_ShouldAuthenticate)
 	{
-		MTRand mtrand1;
+		auto & rand = GetRandomProvider();
-		unsigned int r1 = (mtrand1.randInt() % 1147483647) + 1000000000;
+		unsigned int r1 = rand.RandInt<unsigned int>(1000000000U, 0x7fffffffU);
-		unsigned int r2 = (mtrand1.randInt() % 1147483647) + 1000000000;
+		unsigned int r2 = rand.RandInt<unsigned int>(1000000000U, 0x7fffffffU);
 		std::ostringstream sid;
 		sid << std::hex << r1;
 		sid << std::hex << r2;

src/Simulator/FireSimulator.cpp

@@ -301,7 +301,7 @@ int cFireSimulator::GetBurnStepTime(cChunk * a_Chunk, int a_RelX, int a_RelY, in
 void cFireSimulator::TrySpreadFire(cChunk * a_Chunk, int a_RelX, int a_RelY, int a_RelZ)
 {
 	/*
-	if (m_World.GetTickRandomNumber(10000) > 100)
+	if (GetRandomProvider().RandBool(0.99))
 	{
 		// Make the chance to spread 100x smaller
 		return;
@@ -317,7 +317,7 @@ void cFireSimulator::TrySpreadFire(cChunk * a_Chunk, int a_RelX, int a_RelY, int
 				// No need to check the coords for equality with the parent block,
 				// it cannot catch fire anyway (because it's not an air block)
 
-				if (m_World.GetTickRandomNumber(MAX_CHANCE_FLAMMABILITY) > m_Flammability)
+				if (!GetRandomProvider().RandBool(m_Flammability * (1.0 / MAX_CHANCE_FLAMMABILITY)))
 				{
 					continue;
 				}
@@ -381,7 +381,7 @@ void cFireSimulator::RemoveFuelNeighbors(cChunk * a_Chunk, int a_RelX, int a_Rel
 			return;
 		}
 
-		bool ShouldReplaceFuel = (m_World.GetTickRandomNumber(MAX_CHANCE_REPLACE_FUEL) < m_ReplaceFuelChance);
+		bool ShouldReplaceFuel = (GetRandomProvider().RandBool(m_ReplaceFuelChance * (1.0 / MAX_CHANCE_REPLACE_FUEL)));
 		if (ShouldReplaceFuel && !cRoot::Get()->GetPluginManager()->CallHookBlockSpread(m_World, AbsX, Y, AbsZ, ssFireSpread))
 		{
 			Neighbour->SetBlock(X, Y, Z, E_BLOCK_FIRE, 0);

src/UI/SlotArea.cpp

@@ -1003,8 +1003,7 @@ void cSlotAreaAnvil::OnTakeResult(cPlayer & a_Player)
 	NIBBLETYPE BlockMeta;
 	a_Player.GetWorld()->GetBlockTypeMeta(PosX, PosY, PosZ, Block, BlockMeta);
 
-	cFastRandom Random;
+	if (!a_Player.IsGameModeCreative() && (Block == E_BLOCK_ANVIL) && GetRandomProvider().RandBool(0.12))
-	if (!a_Player.IsGameModeCreative() && (Block == E_BLOCK_ANVIL) && (Random.NextFloat(1.0F) < 0.12F))
 	{
 		NIBBLETYPE Orientation = BlockMeta & 0x3;
 		NIBBLETYPE AnvilDamage = BlockMeta >> 2;
@@ -1578,8 +1577,8 @@ void cSlotAreaEnchanting::UpdateResult(cPlayer & a_Player)
 	{
 		int Bookshelves = std::min(GetBookshelvesCount(*a_Player.GetWorld()), 15);
 
-		cFastRandom Random;
+		auto & Random = GetRandomProvider();
-		int Base = (Random.GenerateRandomInteger(1, 8) + static_cast<int>(floor(static_cast<float>(Bookshelves / 2)) + Random.GenerateRandomInteger(0, Bookshelves)));
+		int Base = (Random.RandInt(1, 8) + (Bookshelves / 2) + Random.RandInt(0, Bookshelves));
 		int TopSlot = std::max(Base / 3, 1);
 		int MiddleSlot = (Base * 2) / 3 + 1;
 		int BottomSlot = std::max(Base, Bookshelves * 2);

src/World.cpp

@@ -245,22 +245,20 @@ void cWorld::CastThunderbolt (int a_BlockX, int a_BlockY, int a_BlockZ)
 
 int cWorld::GetDefaultWeatherInterval(eWeather a_Weather)
 {
+	auto & Random = GetRandomProvider();
 	switch (a_Weather)
 	{
 		case eWeather_Sunny:
 		{
-			auto dif = m_MaxSunnyTicks - m_MinSunnyTicks + 1;
+			return Random.RandInt(m_MinSunnyTicks, m_MaxSunnyTicks);
-			return m_MinSunnyTicks + (m_TickRand.randInt() % dif);
 		}
 		case eWeather_Rain:
 		{
-			auto dif = m_MaxRainTicks - m_MinRainTicks + 1;
+			return Random.RandInt(m_MinRainTicks, m_MaxRainTicks);
-			return m_MinRainTicks + (m_TickRand.randInt() % dif);
 		}
 		case eWeather_ThunderStorm:
 		{
-			auto dif = m_MaxThunderStormTicks - m_MinThunderStormTicks + 1;
+			return Random.RandInt(m_MinThunderStormTicks, m_MaxThunderStormTicks);
-			return m_MinThunderStormTicks + (m_TickRand.randInt() % dif);
 		}
 	}
 
@@ -812,7 +810,7 @@ eWeather cWorld::ChooseNewWeather()
 		case eWeather_Rain:
 		{
 			// 1 / 8 chance of turning into a thunderstorm
-			return ((m_TickRand.randInt() % 256) < 32) ? eWeather_ThunderStorm : eWeather_Sunny;
+			return GetRandomProvider().RandBool(0.125) ? eWeather_ThunderStorm : eWeather_Sunny;
 		}
 	}
 
@@ -1074,7 +1072,7 @@ void cWorld::TickWeather(float a_Dt)
 	if (m_Weather == eWeather_ThunderStorm)
 	{
 		// 0.5% chance per tick of thunderbolt
-		if (m_TickRand.randInt() % 199 == 0)
+		if (GetRandomProvider().RandBool(0.005))
 		{
 			CastThunderbolt(0, 0, 0);  // TODO: find random positions near players to cast thunderbolts.
 		}
@@ -1697,7 +1695,7 @@ void cWorld::GrowTreeImage(const sSetBlockVector & a_Blocks)
 
 bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsByBonemeal)
 {
-	cFastRandom random;
+	auto & random = GetRandomProvider();
 	BLOCKTYPE BlockType;
 	NIBBLETYPE BlockMeta;
 	GetBlockTypeMeta(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1735,7 +1733,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 			}
 			else
 			{
-				BlockMeta += random.NextInt(4) + 2;
+				BlockMeta += random.RandInt(2, 5);
 				BlockMeta = std::min(BlockMeta, static_cast<NIBBLETYPE>(7));
 			}
 			FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1770,7 +1768,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 			}
 			else
 			{
-				BlockMeta += random.NextInt(4) + 2;
+				BlockMeta += random.RandInt(2, 5);
 				BlockMeta = std::min(BlockMeta, static_cast<NIBBLETYPE>(7));
 			}
 			FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1793,7 +1791,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 				}
 				else
 				{
-					BlockMeta += random.NextInt(4) + 2;
+					BlockMeta += random.RandInt(2, 5);
 					BlockMeta = std::min(BlockMeta, static_cast<NIBBLETYPE>(7));
 				}
 				FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1825,7 +1823,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 			}
 			else
 			{
-				BlockMeta += random.NextInt(4) + 2;
+				BlockMeta += random.RandInt(2, 5);
 				BlockMeta = std::min(BlockMeta, static_cast<NIBBLETYPE>(7));
 			}
 			FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1848,7 +1846,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 				}
 				else
 				{
-					BlockMeta += random.NextInt(4) + 2;
+					BlockMeta += random.RandInt(2, 5);
 					BlockMeta = std::min(BlockMeta, static_cast<NIBBLETYPE>(7));
 				}
 				FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, BlockMeta);
@@ -1884,14 +1882,14 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 				{
 					++GrowState;
 				}
-				else if (random.NextInt(99) < 45)
+				else if (random.RandBool(0.45))
 				{
 					++GrowState;
 				}
 
 				FastSetBlock(a_BlockX, a_BlockY, a_BlockZ, BlockType, static_cast<NIBBLETYPE>(GrowState << 3 | TypeMeta));
 			}
-			else if (random.NextInt(99) < 45)
+			else if (random.RandBool(0.45))
 			{
 				GrowTreeFromSapling(a_BlockX, a_BlockY, a_BlockZ, BlockMeta);
 			}
@@ -1905,12 +1903,12 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 			{
 				return false;
 			}
-			MTRand r1;
+			auto & r1 = GetRandomProvider();
 			for (int i = 0; i < 60; i++)
 			{
-				int OfsX = static_cast<int>(r1.randInt(3) + r1.randInt(3) + r1.randInt(3) + r1.randInt(3)) / 2 - 3;
+				int OfsX = (r1.RandInt(3) + r1.RandInt(3) + r1.RandInt(3) + r1.RandInt(3)) / 2 - 3;
-				int OfsY = static_cast<int>(r1.randInt(3) + r1.randInt(3)) - 3;
+				int OfsY = r1.RandInt(3) + r1.RandInt(3) - 3;
-				int OfsZ = static_cast<int>(r1.randInt(3) + r1.randInt(3) + r1.randInt(3) + r1.randInt(3)) / 2 - 3;
+				int OfsZ = (r1.RandInt(3) + r1.RandInt(3) + r1.RandInt(3) + r1.RandInt(3)) / 2 - 3;
 				BLOCKTYPE Ground = GetBlock(a_BlockX + OfsX, a_BlockY + OfsY, a_BlockZ + OfsZ);
 				if (Ground != E_BLOCK_GRASS)
 				{
@@ -1923,7 +1921,7 @@ bool cWorld::GrowRipePlant(int a_BlockX, int a_BlockY, int a_BlockZ, bool a_IsBy
 				}
 				BLOCKTYPE  SpawnType;
 				NIBBLETYPE SpawnMeta = 0;
-				switch (r1.randInt(10))
+				switch (r1.RandInt(10))
 				{
 					case 0:  SpawnType = E_BLOCK_YELLOW_FLOWER; break;
 					case 1:  SpawnType = E_BLOCK_RED_ROSE;      break;
@@ -2031,8 +2029,7 @@ int cWorld::GrowCactus(int a_BlockX, int a_BlockY, int a_BlockZ, int a_NumBlocks
 
 bool cWorld::GrowMelonPumpkin(int a_BlockX, int a_BlockY, int a_BlockZ, BLOCKTYPE a_BlockType)
 {
-	MTRand Rand;
+	return m_ChunkMap->GrowMelonPumpkin(a_BlockX, a_BlockY, a_BlockZ, a_BlockType);
-	return m_ChunkMap->GrowMelonPumpkin(a_BlockX, a_BlockY, a_BlockZ, a_BlockType, Rand);
 }
 
 
@@ -2162,6 +2159,7 @@ bool cWorld::WriteBlockArea(cBlockArea & a_Area, int a_MinBlockX, int a_MinBlock
 
 void cWorld::SpawnItemPickups(const cItems & a_Pickups, double a_BlockX, double a_BlockY, double a_BlockZ, double a_FlyAwaySpeed, bool IsPlayerCreated)
 {
+	auto & Random = GetRandomProvider();
 	a_FlyAwaySpeed /= 100;  // Pre-divide, so that we don't have to divide each time inside the loop
 	for (cItems::const_iterator itr = a_Pickups.begin(); itr != a_Pickups.end(); ++itr)
 	{
@@ -2171,9 +2169,9 @@ void cWorld::SpawnItemPickups(const cItems & a_Pickups, double a_BlockX, double
 			continue;
 		}
 
-		float SpeedX = static_cast<float>(a_FlyAwaySpeed * (GetTickRandomNumber(10) - 5));
+		float SpeedX = static_cast<float>(a_FlyAwaySpeed * Random.RandInt(-5, 5));
-		float SpeedY = static_cast<float>(a_FlyAwaySpeed * GetTickRandomNumber(50));
+		float SpeedY = static_cast<float>(a_FlyAwaySpeed * Random.RandInt(50));
-		float SpeedZ = static_cast<float>(a_FlyAwaySpeed * (GetTickRandomNumber(10) - 5));
+		float SpeedZ = static_cast<float>(a_FlyAwaySpeed * Random.RandInt(-5, 5));
 
 		cPickup * Pickup = new cPickup(
 			a_BlockX, a_BlockY, a_BlockZ,
@@ -2310,10 +2308,11 @@ UInt32 cWorld::SpawnPrimedTNT(double a_X, double a_Y, double a_Z, int a_FuseTick
 		TNT = nullptr;
 		return cEntity::INVALID_ID;
 	}
+	auto & Random = GetRandomProvider();
 	TNT->SetSpeed(
-		a_InitialVelocityCoeff * (GetTickRandomNumber(2) - 1), /** -1, 0, 1 */
+		a_InitialVelocityCoeff * Random.RandInt(-1, 1),
 		a_InitialVelocityCoeff * 2,
-		a_InitialVelocityCoeff * (GetTickRandomNumber(2) - 1)
+		a_InitialVelocityCoeff * Random.RandInt(-1, 1)
 	);
 	return TNT->GetUniqueID();
 }
@@ -3793,6 +3792,15 @@ UInt32 cWorld::CreateProjectile(double a_PosX, double a_PosY, double a_PosZ, cPr
 
 
 
+int cWorld::GetTickRandomNumber(int a_Range)
+{
+	return GetRandomProvider().RandInt(a_Range);
+}
+
+
+
+
+
 void cWorld::TabCompleteUserName(const AString & a_Text, AStringVector & a_Results)
 {
 	typedef std::pair<AString::size_type, AString> pair_t;

src/World.h

@@ -28,7 +28,6 @@
 #include "MapManager.h"
 #include "Blocks/WorldInterface.h"
 #include "Blocks/BroadcastInterface.h"
-#include "FastRandom.h"
 #include "EffectID.h"
 
 
@@ -801,8 +800,8 @@ public:
 	Item parameter is currently used for Fireworks to correctly set entity metadata based on item metadata. */
 	UInt32 CreateProjectile(double a_PosX, double a_PosY, double a_PosZ, cProjectileEntity::eKind a_Kind, cEntity * a_Creator, const cItem * a_Item, const Vector3d * a_Speed = nullptr);  // tolua_export
 
-	/** Returns a random number from the m_TickRand in range [0 .. a_Range]. To be used only in the tick thread! */
+	/** Returns a random number in range [0 .. a_Range]. */
-	int GetTickRandomNumber(int a_Range) { return static_cast<int>(m_TickRand.randInt(a_Range)); }
+	int GetTickRandomNumber(int a_Range);
 
 	/** Appends all usernames starting with a_Text (case-insensitive) into Results */
 	void TabCompleteUserName(const AString & a_Text, AStringVector & a_Results);
@@ -880,9 +879,6 @@ private:
 	/** The dimension of the world, used by the client to provide correct lighting scheme */
 	eDimension m_Dimension;
 
-	/** This random generator is to be used only in the Tick() method, and thus only in the World-Tick-thread (MTRand is not exactly thread-safe) */
-	MTRand m_TickRand;
-
 	bool m_IsSpawnExplicitlySet;
 	double m_SpawnX;
 	double m_SpawnY;

tests/FastRandom/FastRandomTest.cpp

@@ -15,14 +15,13 @@ static void TestInts(void)
 	cFastRandom rnd;
 	int sum = 0;
 	const int BUCKETS = 8;
-	int Counts[BUCKETS];
+	int Counts[BUCKETS] = {0};
-	memset(Counts, 0, sizeof(Counts));
 	const int ITER = 10000;
 	for (int i = 0; i < ITER; i++)
 	{
-		int v = rnd.NextInt(1000);
+		int v = rnd.RandInt(1000);
 		assert_test(v >= 0);
-		assert_test(v < 1000);
+		assert_test(v <= 1000);
 		Counts[v % BUCKETS]++;
 		sum += v;
 	}
@@ -43,12 +42,11 @@ static void TestFloats(void)
 	cFastRandom rnd;
 	float sum = 0;
 	const int BUCKETS = 8;
-	int Counts[BUCKETS];
+	int Counts[BUCKETS] = {0};
-	memset(Counts, 0, sizeof(Counts));
 	const int ITER = 10000;
 	for (int i = 0; i < ITER; i++)
 	{
-		float v = rnd.NextFloat(1000);
+		float v = rnd.RandReal(1000.0f);
 		assert_test(v >= 0);
 		assert_test(v <= 1000);
 		Counts[static_cast<int>(v) % BUCKETS]++;
@@ -76,7 +74,7 @@ static void TestReCreation(void)
 	for (int i = 0; i < ITER; ++i)
 	{
 		cFastRandom rnd;
-		int val = rnd.NextInt(10);
+		int val = rnd.RandInt(9);
 		if (val == lastVal)
 		{
 			numSame += 1;