I've been wondering if 1. Would a 64 bit positioning system make it possible to transition from earth to space and further to another planet, kinda like Kerbal Space Program but without the origin shifting so that real data could be derived from it. 2. Would it possible to do so and how?
Just figure out what each integer increment represents and you're basically done. Millimetres should be sufficient, as that's still a +/- ten trillion kilometre range if you're using a signed value.
That's going to offer more consistency in positioning than a floating point value, but the downside is each xyz vector will be 192 bits, or 24 bytes.