I would rather check if a guy is close to any grenade in the mission
Should be possible..
In order to get any grenade/shell detected you would need a constant fast sqs loop that checks the surroundings of the unit with nearestObject.
Then, once a certain type of object is detected, the script would set a unit specific global variable true, which would then be checked in the units dammaged eventHandler..
(the global variable would be needed because otherwise you can't 'detect' what hit the guy..)
The dammaged eventHandler would execute a script that would first check if the above mentioned global variable was true or not...
If true, then the script would check whether the unit was killed and if not, where the unit was hit and how much damage was inflicted...
Then according to that info the model would be replaced with one that would have it's arm, leg or what ever, severed off...
That inflicted damage stuff would be done because you wouldn't wanna have someones arm torn off by just a tiny bit of damage
But I'm speaking about acting under OFP damage 'engine', if you would like to have just the distance of the grenade/shell impact as a damage factor you would need to check the distance in the looping sqs searching around the unit...
The looping nearestObject search would need to be insanely fast (most likely) which means that there will be a major performance hit; the more units the more the game performance would suffer...
On that barrage script you would again need nearestObject..
Once the _obj is created another script would be executed which would monitor the _obj untill it dies constantly recording the _obj's position..
Once the _obj dies a few nearestObject searches would be performed on and around the last known position of the _obj.
Then, if a man class object was found the man's position would be compared with the _obj's last known position and if the difference between thos two positions is short enough the man would get some of it's limbs severed...
This same method could be used on weapons/vehicles firing shells/grenades (in their fired eventHandler) to do what my first example does...
This method should not cause as much performance hit as the first example...
Only problem is that following the fired shells/grenades does not necessarily provide very exact position data... OFP sqs can not keep up with projectiles travelling very very fast like for example tank fired shells do...
Slower grenades and stuff should provide a bit more exact position data as they travel slower...
But this is all just theory, practise can be a whole different deal...
And of course neither of these methods work on the player unit, which is a major drag...
Oh, and all ideas hereby copyrighted ;D ;D ;D