[tantalor]

Collisions are extremely unlikely. You will know if a collision occurred if the answer is rejected. If that happens you can tweak the hash algorithm and try again. This would allow saving coordinates outside of the [-1000, 30000] range.

I think it would be easier to reason about because,

1. KISS: You don't need to verify the encoding code is correct.

2. YAGNI: The program doesn't require reading the coordinates back out, so the program should not store the coordinates in a format that can do that.