I suppose you could try using
group reveal unit
Operand types:
group: Object or Group
unit: Object
Type of returned value:
Nothing
Description:
Reveal unit to group, do not care if it can know about it or not.
Example:
soldierOne reveal soldierTwo
in a trigger activated repeatedly and set to go off if an enemy soldier enters in it's area.
Maybe something like this in the 'on activation' field
{[_x] exec "reveal.sqs"} forEach thislist
?count > 0: exit
_unit = _this select 0
count _unit = _imax
_i = -1
count = 1
#reveal
?_i >= _imax: exit
~0.1
_i = _i+1
MyGroup reveal (_Unit select _i)
goto "reveal"
The size of your trigger will determine how well they see. You'll have to name the trigger and make a loop script to move the trigger with the enemy. This won't propably work, but I think I just may be onto something here