There was a 3d engine a while back, focused on collision and pathing, which used 32-bit fixed point values for everything, citing this problem. If you divide o

There was a 3d engine a while back, focused on collision and pathing, which used 32-bit fixed point values for everything, citing this problem. If you divide out your game world size by the resolution a 32-bit number offers, it ends up being very practical. However, I don't know how overflow was handled for intermediates, if there was "enough" buffer around the outside of the world or if the math just worked out. Certainly 64-bit fixed point would be "sufficient".