Two strings are created :
STRING1 = “[NONCE]:[SERVER SEED]:[NONCE]”
STRING2 = “[NONCE]:[CLIENT SEED]:[NONCE]”
Then HMAC-SHA512 is used to hash STRING1 with STRING2 as the secret key, giving us a 128 character hex string.
The first 8 characters of the hex string are taken and converted to a decimal.
This decimal is then divided by 429496.7295 and rounded off to the nearest whole number.
This whole number is used as your roll, with the maximum possible value being 10,000.