Replicate Starbound's tile randomness

[blixt]

Every tile material has several variants to look less repetitive. These variants are chosen based on a pseudorandom pattern that follows a certain set of rules (so the tiles don't change every time they're rendered).

The pattern would most likely consist of the following parameters:

• A constant seed for foreground tiles and another for background tiles (possibly also ones for material mods)
• The world seed (so every world has a different pattern)
• The X, Y coordinates

Additionally, depending on the hashing function, it may also consist of:

• An initial hash value
• A prime number to multiply with

Based on research and digging through Starbound's binary files, I've found the following:

• At some point Starbound used FNV hashing but possibly not anymore (several FNV constants are not in the binary)
• The Starbound binary does contain the full set of primes used by xxHash
• Additionally, the binary contains at least the following primes:
  • 16,777,619 (associated with 32-bit FNV)
  • 1,099,511,628,211 (associated with 64-bit FNV)
  • 2,938,728,349 (appears to be unique to Starbound)