Failed implementation of xoshiro256++ becaause Lua doesn't have an integer type :-( :-( :-( :-( :-( :-( :-(

worldeditadditions/utils/random.lua

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+--- Implementation of the xoshiro++ random number generation algorithm.
+-- Ported from C by Starbeamrainbowlabs
+-- @ref https://en.wikipedia.org/wiki/Xorshift#xoshiro_and_xoroshiro
+-- @class
+local Xoshiro = {}
+Xoshiro.__index = Xoshiro
+
+--- Creates a new Xoshiro instance.
+-- @returns		Xoshiro		The new Xoshiro instance.
+function Xoshiro.new(seed)
+	seed = seed or 4898416254654
+	local result = {
+		state = {
+			34862381629 ^ seed,
+			87782734023 ^ seed,
+			59217486042 ^ seed,
+			68724585416 ^ seed
+		}
+	}
+	setmetatable(result, Xoshiro)
+	return result
+end
+
+--- Polyfill for the bitshift left operator that's missing in Lua.
+-- @source https://ebens.me/post/simulate-bitwise-shift-operators-in-lua/
+-- @param	value	number	The number to bitshift left.
+-- @param	places	number	The number of bits to shift it by to the left.
+function Xoshiro._bitshift_left(value, places)
+	return value * 2 ^ places
+end
+
+--- Polyfill for the bitshift right operator that's missing in Lua.
+-- @source https://ebens.me/post/simulate-bitwise-shift-operators-in-lua/
+-- @param	value	number	The number to bitshift right.
+-- @param	places	number	The number of bits to shift it by to the right.
+function Xoshiro._bitshift_right(value, places)
+	return math.floor(value / 2 ^ places)
+end
+
+-- Bitwise OR polyfill.
+-- The source also has polyfills for bitwise AND, NOT, and XOR.
+-- @source https://stackoverflow.com/a/25594410/1460422
+-- @param	a	number	The left-hand argument to the bitwise or operation.
+-- @param	b	number	The right-hand argument to the bitwise or operation.
+-- @returns	number		The result of the bitwise or operation.
+function Xoshiro._bitwise_or(a,b)
+    local p,c=1,0
+    while a+b>0 do
+        local ra,rb=a%2,b%2
+        if ra+rb>0 then c=c+p end
+        a,b,p=(a-ra)/2,(b-rb)/2,p*2
+    end
+    return c
+end
+
+-- Bitwise XOR polyfill.
+-- The source also has polyfills for bitwise AND, OR, and NOT.
+-- @source https://stackoverflow.com/a/25594410/1460422
+-- @param	a	number	The left-hand argument to the bitwise xor operation.
+-- @param	b	number	The right-hand argument to the bitwise xor operation.
+-- @returns	number		The result of the bitwise xor operation.
+function Xoshiro._bitwise_xor(a,b)
+    local p,c=1,0
+    while a>0 and b>0 do
+        local ra,rb=a%2,b%2
+        if ra~=rb then c=c+p end
+        a,b,p=(a-ra)/2,(b-rb)/2,p*2
+    end
+    if a<b then a=b end
+    while a>0 do
+        local ra=a%2
+        if ra>0 then c=c+p end
+        a,p=(a-ra)/2,p*2
+    end
+    return c
+end
+
+
+function Xoshiro._rol64(x, k)
+	return Xoshiro._bitwise_or(
+		Xoshiro._bitshift_left(x, k),
+		Xoshiro._bitshift_right(x, 64 - k)
+	)
+end
+
+function Xoshiro.random_raw(self)
+	local result = self.state[1] + self.state[4]
+	local t = Xoshiro._bitshift_right(self.state[2], 17)
+	
+	self.state[3] = Xoshiro._bitwise_xor(self.state[3], self.state[1])
+	self.state[4] = Xoshiro._bitwise_xor(self.state[4], self.state[2])
+	self.state[2] = Xoshiro._bitwise_xor(self.state[2], self.state[3])
+	self.state[1] = Xoshiro._bitwise_xor(self.state[1], self.state[4])
+	
+	self.state[3] = Xoshiro._bitwise_xor(self.state[3], t)
+	self.state[4] = Xoshiro._rol64(self.state[4], 45)
+	
+	return result
+end
+
+function Xoshiro.random(self)
+	return self:random_raw()
+end
+
+print("_G", _G)
+
+for key,value in pairs(_G) do
+	print(key, "→", value)
+end
+
+return Xoshiro

worldeditadditions/utils/random_test.lua

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+Xoshiro = require("random")
+
+rand = Xoshiro.new()
+
+print(rand)
+
+for i=1,25 do
+	print(i, "→", rand:random())
+end