the most common way is to make a small sphere with a collision box
make object sphere objectnumber,radius
turn object collision on objectnumber
and place it at the camera's co-ordinates
position object objectnumber,camera position x(),camera position y(),camera position z()
then set it to face the same way as the camera
set object to camera orientation objectnumber
then move it forward slowly
move object objectnumber,movementvalue
then check if it hits anything..
for enemy=starting_enemy_objectnumber to end_enemy_objectnumber
if object collision(objectnumber,0) then delete object enemy : `etc
next enemy
well that's the basics.... u'll need a little more but that should be enough to get u on your way.
here's the code all together..
make object sphere objectnumber,radius
position object objectnumber,camera position x(),camera position y(),camera position z()
set object to camera orientation objectnumber
move object objectnumber,movementvalue
for enemy=starting_enemy_objectnumber to end_enemy_objectnumber
if object collision(objectnumber,0) then delete object enemy : `etc
next enemy
life's one big game
spec= 1.6ghz, 512mb ram, 128mb gpu, directx 9.0c, dbpro and classic