Can we got some friendly fire threshold for reaction shots?

[Ashery]

Serves me right for moving my Colonel HW guy up a couple tiles to avoid stacking three soldiers in a line (Watching a long hall in a large base assault with two snipers and the HW; alien grenade spam has already taken two soldiers due to mistakes on my part), but this is now the second time my sniper has brained a soldier of mine due to friendly fire on a reaction shot. The first was pretty much a rookie, but this time it was my second longest serving soldier...second behind the very sniper that killed'em.

It'd probably be easier to implement the threshold instead of redoing the whole cover system so that a unit standing two tiles back from a crouching unit doesn't have the maximum chance of hitting the crouching soldier. Doesn't even have to be a soldier; all cover has this element.

The damn sniper has 101 accuracy, too. First time I've rage quit the game.

[MrPyro]

I'm sure this has been mentioned before, and has been implemented; might just need tweaking a bit.

On the flip side, the same applies to the aliens as well; there's nothing quite as funny as watching an Andron with a plasma cannon gib the Harridan standing in front of him.

[Chris]

This should already be working, but apparently it is not. It happened to me a couple of times on my playthroughs, too - ironically the higher the accuracy of your soldier, the more likely he is to hit your own soldier (rather than hitting nothing at all, that is - he's even more likely to actually hit the target).

[jeon]

There is an incorrect parameter set in the config.xml that heavily affects the friendly fire issue.

<NoTargetPenalty>0.75</NoTargetPenalty>

I read that the intent of this parameter is to reduce the chance of hitting a target that you are not targeting by 75% such that 75% of your hit chance applies to whatever you are targeting, and 25% to the obstructing object.

The problem is, the way the number is used is the opposite of that intent. It actually corresponds to a 75% chance to hit the obstructing object and a 25% chance to hit the targeted object. I recommend changing it to:

<NoTargetPenalty>0.25</NoTargetPenalty>

[Chris]

That's not quite what's happening. It's just applying 75% of the stopping chance of the blocking unit at the moment. That's why if you set the value to 1, the units still only reduce accuracy by 40% or so.

[jeon]

That's not quite what's happening. It's just applying 75% of the stopping chance of the blocking unit at the moment. That's why if you set the value to 1, the units still only reduce accuracy by 40% or so.

I'm not quite sure I understand what you are explaining here.

The stopping chance of the blocking unit is the NoTargetPenalty (0.75) * the chance to hit the tile (without obstructions), which is soldier accuracy * weapon accuracy * range penalty. The stopping chance of a blocking unit is decreased by 20% if it is crouching. If I set the value to 1, a blocking unit will reduce the accuracy exactly proportionate relative to the shot, creating some interesting results. A shot that would have a 100% chance to hit a tile before close combat bonus and being capped at 95%, would have a 100% chance of hitting the block unit and make the chance to hit the tile 1%, which is still actually hittable if you roll a 1. The effects aren't as noticeable with lower accuracy soldiers and weapons though. Once you have a soldier with 90+ accuracy or are taking aimed shots with snipers does it really show up in force because it is easy to hit 100+ hit chance with them.

Here's an example:

Soldier with assault rifle and 90 accuracy with the 0.75 NoTargetPenalty.

If he does an aimed shot, it will have 108% chance to hit any tile within his range. If there is a soldier or alien in the way of his shot within his range, the blocking unit will have a 108 * .75 = 81% chance to stop the shot. His chance to hit a target not in close combat range would be 20.5% ((100-81)% * 108%). On each shot he would have a 20.5% chance to hit the target, a 64.4% ((100-20.5)% * 81%) chance to hit the blocking unit, and the remaining 15.1% chance to miss both of them.

If he took a snap shot instead, it has a 72% chance to hit a tile. A blocking unit will have a 54% chance to stop a shot. The chance to hit his target is 33.1%. On each shot he would have a 33.1% chance to hit the target, a 36.1% chance to hit the blocking unit, and a 30.8% chance of missing both.

This also has a similar effect if shooting through smoke. Assume there is enough smoke to reduce the chance to hit to 1%. If you target behind an alien with your 108% chance to hit shot, you will have an 81% chance to hit the alien.

Here's the above numbers if the NoTargetPenalty is set at 0.25:

Aimed shot has a 78.8% chance to hit the target, a 5.7% chance to hit the blocking unit, and the remaining 15.5% chance to miss both.

Snap shot has a 59% chance to hit the target, a 7.4% chance to hit the blocking unit, and the remaining 33.6% chance to miss both.

Shooting an aimed shot through the smoke will have a 27% chance of hitting the alien.

Here's some (poorly done) pictures to show the effects of each setting with approximately 90 accuracy soldiers: