That is one way of doing it, quick and easy. DBP has it's own way of dealing with line-of-sight, look it up in the manual.
Or you could have a long, thin hidden box extending out from the player at all times and checking the boundingboxes for collisions.
Or you could use maths to see if the line of sight from the player cuts though the radius/box of the object.(Although I never got that to work, I've seen it used extensivly. Look up the formula in a mathbook or see it here: http://astronomy.swin.edu.au/~pbourke/geometry/sphereline/ )
Or you could use pythagoras theorem to work out the angle between the player and the object. The last one I've used before and it works... kinda.
400 Mhz, 120 Meg, TNT2 - and then some...
