public Int3 NormalizeTo (int newMagn) {
float magn = magnitude;
if (magn == 0) {
return this;
}
x *= newMagn;
y *= newMagn;
z *= newMagn;
x = (int)System.Math.Round (x/magn);
y = (int)System.Math.Round (y/magn);
z = (int)System.Math.Round (z/magn);
return this;
}