Of course you would only use a slight turn if you knew that the singularity was going to occur before you used aligntovector. Is that really such a hardship?
With the deltaroll function you will only ever return -180 or 180 when the target is directly behind the missile so it will work perfectly. Trust me, I have had to use it myself when doing 2d in 3d on a single plane. Alternatively just use the x/z plane and deltayaw - it's six and half a dozen.
BTW, I use aligntovector on the z axis for those missiles.
function MYaligntoVector( entity, vx#, vy#, axis = 1, rate# = 1 ) if vx = 0 and vy < 0 turnentity entity, 0,0,-.0001 aligntovector entity, vx, vy, 0, axis, rate# end function
With the deltaroll function you will only ever return -180 or 180 when the target is directly behind the missile so it will work perfectly. Trust me, I have had to use it myself when doing 2d in 3d on a single plane. Alternatively just use the x/z plane and deltayaw - it's six and half a dozen.
BTW, I use aligntovector on the z axis for those missiles.