Ranged weapon: Number of attacks before enemy closes distance

[KaiRayne]

Disclaimer: I haven't played or GM'ed in a few years.

What I'm trying to figure out is how many attacks I could make with a longbow say, against a group on enemies, before they close to melee range.

Assume: My character has a longbow. I see a group of med size creatures in the distance (no cover or concealment).
They don't see me.

My questions are:
A: At what distance do I first see them?
B: At what distance can I make a ranged attack with my bow? (I assume 100 feet).
C: Assuming they start running towards me once they realize they are being fired upon, how many arrows can I fire before they arrive at my location?
D: What are 10 range increments for a longbow, in terms of distance (feet)?

For C above: I'm kinda guessing 2:
First for a surprise round/action and
Second as they close to me (running at 120 feet per round).

BUT:
1: It seems to me that I should be able to fire off more arrows as they run towards me.

2: I'm pretty sure I'm missing something about range increments/penalties, notably this:
"Range: Any attack at more than this distance is penalized for range. Beyond this range, the attack takes a cumulative –2 penalty for each full range increment (or fraction thereof) of distance to the target. For example, a dagger (with a range of 10 feet) thrown at a target that is 25 feet away would incur a –4 penalty. A thrown weapon has a maximum range of five range increments. A projectile weapon can shoot to 10 range increments."
Hence question D, above.

Advice/answers/opinions much appreciated thanx.

[Snakers]

Ten range increments for a 110 range longbow is 1100 feet at a -10 penalty.

[Matthew Downie]

KaiRayne wrote:

A: At what distance do I first see them?

Depends on the terrain and weather conditions. I don't think there's a RAW answer.

KaiRayne wrote:

B: At what distance can I make a ranged attack with my bow? (I assume 100 feet).

"A projectile weapon can shoot to 10 range increments."

A longbow has a range increment of 100 feet.
So the maximum range of a longbow is 1000 feet. At this distance it gets something like -20 to hit.

KaiRayne wrote:

C: Assuming they start running towards me once they realize they are being fired upon, how many arrows can I fire before they arrive at my location?

Depends on their speed and how many shots you can fire per round.

If they are running towards you at 90 feet per round over a distance of 1000 feet, that's 11 rounds. If you can fire two shots per round, that's 22 shots.

D: See B.

However, in general the first distance you see your enemy at is the size of the GM's map.

[KaiRayne]

Thanx for the info. The increment info was particularly helpful.

It seems that doing this does require a bit of bookkeeping in terms of ranges, range increments, how far a char can see, how fast your enemies approach, how many attacks you get, etc etc etc . . .

Seems that the vision issue (how far can a char see) has been raised previously.

Appreciated.

[RealAlchemy]

For A, consider the Perception skill. Notice a visible creature is DC 0 +1 per 10 feet.

[Kobold Commando]

Varies too much by character. There are a very few ways to make the range and number of attacks effectively infinite, but those are extreme outliers. Given optimal conditions the answer is shots per round * (distance enemies first spotted at ÷enemy max move speed), plus or minus a few shotd depending on suprise and who wins initiative.