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--[[
Simple deterministic Lua PRNG. Meant when you want worse quality random
numbers and more deterministic than what the rnd module provides.
--]]
prng = { z = 1 }
function prng.init( num )
prng.z = num
end
function prng.initHash( str )
local hash = 5381
local bytes = { string.byte( str, 1, string.len(str) ) }
for _,c in ipairs(bytes) do
hash = hash * 33 + c
end
prng.z = math.abs( math.fmod( hash, 4294967295 ) )
end
function prng.num ()
prng.z = math.abs( math.fmod( prng.z * 279470273, 4294967295 ) )
return prng.z / 4294967295
end
function prng.range( min, max )
local n = prng.num()
return math.floor( min + n*(max-min) + 0.5 )
end
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