Cover as a Mechanic

[Diarmuid]

So last night we're in a combat with some archers firing from windows at our group and trying to figure out how their cover should be applied became a discussion.

The crux of the discussion stemmed from this sentence in the SRD:

"To determine whether your target has cover from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that blocks line of effect or provides cover, or through a square occupied by a creature, the target has cover (+4 to AC)."

I've bolded the part that caused the most headache and I'll explain why. Using that logic in its strictest form, it would seem that firing from cover is just as detrimental to the attacker as it is to the target.

The window/shutters/etc are what are providing the cover. In the case of someone firing from outside in, drawing that line would pass "through" the window/shutter square and would incur the cover bonus. But...flipping the coin, when drawing that same line from the person inside the building the line still goes through the "cover" square.

Is this how it's intended?

[nightwyrm]

I've bolded the part that caused the most headache and I'll explain why. Using that logic in its strictest form, it would seem that firing from cover is just as detrimental to the attacker as it is to the target.

Is this how it's intended?

Don't know if that's what's the designers intended, but that's the way the rules work as written. Another reason why weapon-based ranged combat sucks in 3e.

[big teej]

So last night we're in a combat with some archers firing from windows at our group and trying to figure out how their cover should be applied became a discussion.

The crux of the discussion stemmed from this sentence in the SRD:

"To determine whether your target has cover from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that blocks line of effect or provides cover, or through a square occupied by a creature, the target has cover (+4 to AC)."

I've bolded the part that caused the most headache and I'll explain why. Using that logic in its strictest form, it would seem that firing from cover is just as detrimental to the attacker as it is to the target.

The window/shutters/etc are what are providing the cover. In the case of someone firing from outside in, drawing that line would pass "through" the window/shutter square and would incur the cover bonus. But...flipping the coin, when drawing that same line from the person inside the building the line still goes through the "cover" square.

Is this how it's intended?

I've always made the following distinction.

"if you are "taking cover" behind an object (boulder, shuttered window, parapet, etc.) and firing around it, you take no penalty. if you are 'hiding' (for lack of a better term) behind an object, both sides take the penalty.


example.

lets say there is a boulder between you and an oponent that is 50 feet away (and the boulder is equidistant)

the cover bonus would apply to both parties.

if however, you were standing right next to the boulder, only the opponent would take the penalty.


unrelated tangent: I have noticed in Dragon Age that regardless of what side of a barricade you are standing on, it tends to block your shots, but it doesn't interfere with the enemies in the same fashion.

[Eloel]

So last night we're in a combat with some archers firing from windows at our group and trying to figure out how their cover should be applied became a discussion.

The crux of the discussion stemmed from this sentence in the SRD:

"To determine whether your target has cover from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that blocks line of effect or provides cover, or through a square occupied by a creature, the target has cover (+4 to AC)."

I've bolded the part that caused the most headache and I'll explain why. Using that logic in its strictest form, it would seem that firing from cover is just as detrimental to the attacker as it is to the target.

The window/shutters/etc are what are providing the cover. In the case of someone firing from outside in, drawing that line would pass "through" the window/shutter square and would incur the cover bonus. But...flipping the coin, when drawing that same line from the person inside the building the line still goes through the "cover" square.

Is this how it's intended?

You're missing an important part.
Attacker chooses a corner of square, and draws lines to all enemy corners.
I have nothing better to do, so here is a picture for you :smallsmile:
Red is cover-granting object, blue is in cover, green is not.
http://img15.imageshack.us/img15/2900/coveredc.png

[Diarmuid]

Ahhhhh, that's exactly the piece of it that I was missing. Thank you very much for the picture and the explanation.

Edit - So with that understanding...what AC would a caster need to hit for putting a fireball through an arrowslit? 10? 14 (10+4 cover)? 18 (10 + 8 improved cover)?

[FMArthur]

If arrow slits or cover entries don't say anything, it's all from Fireball's text - you just need to be able to "hit" the opening. It doesn't give itself cover or anything, so it's just 10 + size bonus to AC. You'd have to gauge its size bonus based on the chart for creatures here (http://www.d20srd.org/srd/combat/movementPositionAndDistance.htm#bigandLittleCreatu resInCombat) I guess. A Tiny opening would have AC 12, and a Fine opening would have AC 18.