now, what abut loss of precision when converting to camera relative? just have to make sure you have enough decimal places in your fixed point eh? and your integer parts don't get too big?
another issue: true range checks (pythagorean) require squaring dx and dz (and dy for 3d range). that could lead to overflow with signed int and values on the order of 50 million. 50 meg ^2 = 250 trillion (?). time for long long, eh?
do not check distance like this. If you want to find out wheather object falls into interactive scene, just examine its X value with global scene position value, then Y value with scene value, or also Z if you are not CPU overheaded and have also up down complexity, (like an universe fly game). The best scale for me, since I needed fingers on hands moving , or even better details, was adopted from 3ds MAX, 1 float is 1 meter. Heavenly precision leaving me to bunch of meters