The CRC32 ISO HDLC algorithm is used by FrooxEngine to derive the color of an unknown C# type in ProtoFlux. This is done by computing the CRC of the type's name (without generic parameters, if any).
Function | Purpose | Example |
---|---|---|
crc32_hex |
Computes the hexadecimal CRC32 checksum of the given string | {{#invoke:CRC_32_ISO_HDLC|crc32_hex|IAsset}}
|
The following functions are exported, but not invokable by Media Wiki.
Function | Purpose | Example |
---|---|---|
crc32 |
Computes the CRC32 checksum of the given string | crc32("IAsset")
|
Example: crc32("IAsset") = Script error: The function "crc32_hex" does not exist.
(check: 9CD97842
)
-- CRC_32_ISO_HDLC implementation using a lookup table
local p = {}
local lookup = mw.loadData("Module:CRC_32_ISO_HDLC_LOOKUP")
local bit32 = require("bit32")
function crc32_update(state, bval)
return bit32.bxor(lookup[bit32.band(bit32.bxor(state, bval), 0xff)], bit32.rshift(state, 8))
end
function p.crc32(str)
local state = 0xffffffff
for i=1,#str do
state = crc32_update(state, string.byte(str, i))
end
return bit32.xor(state, 0xffffffff)
end
return p