[RAW] Compendium of Sense Rolls clarifications (looking for one . . .)

[McAllister]

Originally Posted by Gollum

And don't forget the very basic rule: mundane tasks made in ordinary nonadventuring situation don't require any roll. If you didn't hear what your friend said, you just ask him to repeat.

I don't find this to be helpful in the context of vicky's inquiry. Sure, if I were in the middle of playing a game, none of us would roll Sense rolls for normal conversation, but this is GURPS, god dammit, so if people can reliably understand each others' conversations at normal conversations distances, there must be a series of modifiers that make it so.

So, in short, people don't roll for things that are trivially easy, but sometimes it's worthwhile to figure out WHY the thing is trivially easy.

As far as hearing goes, I support a TDM for the source of the sound facing the hearer and a TDM for a speaker raising their voice to make sure it can be understood in a conversation. Potentially, also a TDM for the hearer facing the source of the sound, but it's possible that that's the baseline and there should be a penalty for sounds from other directions. If all these TDMs apply and are are +2, then normal conversation situations only fail on 17-18, which seems right.

[Anthony]

Realistically, hearing is hugely dependent on the quantity of environmental noise, and should change very rapidly from guaranteed detection to no detection (-1 per doubling in range is too small, it should probably be more like -5).

[Gollum]

Originally Posted by McAllister

I don't find this to be helpful in the context of vicky's inquiry.

To best understand what I want to mean, just compare hearing rolls to Driving rolls. In reality, driving is dangerous. You can have an accident and die just while you commute work. And if you look at the examples given in the table of difficulty modifiers, you will immediately notice that bonuses for ordinary driving are not so high.

+2 or +3 – Very Favorable. Mildly risky tasks that most people would undertake without hesitation. Example: A Driving roll to commute to work in a teeming metropolis. (Basic Set, page 345)

So, normally, an average driver (Driving skill-10) would have a lot of problems while commuting work in a big town. But an effective driving skill of 17 still means a lot of possible problems when you go to work and go back home every days...

That is why the rules as written explicitly say that there is no roll for driving into town.

The GM should not require rolls for . . .
• Utterly trivial tasks, such as crossing the street, driving into town, feeding the dog, finding the corner store, or turning on the computer. (GURPS Lite, page 2)

So, if driving into town, which is risky in reality, is supposed to be automatically successful, hearing someone talking to you is also automatically successful, no matter the positive or negative modifiers.

Originally Posted by McAllister

Sure, if I were in the middle of playing a game, none of us would roll Sense rolls for normal conversation, but this is GURPS, god dammit, so if people can reliably understand each others' conversations at normal conversations distances, there must be a series of modifiers that make it so.

Note that following the modifiers as given in the rules (Basic Set, page 358), hearing a normal conversation at 4 yards gives a -2 penalty, which means that average Joe has an effective skill of 12 (75% chance of succeeding) if you also apply the same +4 for ordinary task than for driving skill. And in normal conditions, that is, about one yard away, average Joe has an effective skill of 14 (90% chance of succeeding). These score may not be as high as driving into a big town, they are still not low.

Originally Posted by McAllister

So, in short, people don't roll for things that are trivially easy, but sometimes it's worthwhile to figure out WHY the thing is trivially easy.

As far as hearing goes, I support a TDM for the source of the sound facing the hearer and a TDM for a speaker raising their voice to make sure it can be understood in a conversation. Potentially, also a TDM for the hearer facing the source of the sound, but it's possible that that's the baseline and there should be a penalty for sounds from other directions. If all these TDMs apply and are are +2, then normal conversation situations only fail on 17-18, which seems right.

Yes, if we add another +2 for the hearer facing the source of the sound and for the speaker raising his voice instinctively, it improves average Joe's effective skill to 16 at one yard and to 14 at 4 yards, maybe a bit more.

Now, what I wanted to add with my note is: no roll for utterly trivial and mundane tasks is a more important rule than every of these different modifiers. It comes before the explanation of modifiers in GURPS rules organization and, in my humble opinion has to be reminded in Vicky's uFAQ. A lot of criticisms saying that GURPS is not realistic just came from the forgetting of this very simple but very important rule - which is not the case for Vicky, of course!

[sir_pudding]

Originally Posted by Gollum

Trying to hit a target at point blank range, for instance, requires a roll, even if the target is stationary. So, even if reason would indicate that trying to stealth someone who doesn't pay any attention to his surrounding is an utterly trivial task in reality, it is not in GURPS. It requires a roll: exactly as the target can suddenly move in the hit-at-point-blank-range situation, the attention of the victim of the stealth can suddenly be attracted by a light, a movement or a noise in the surrounding.

If the person is totally insensate or utterly unconcerned there is no risk, and therefore there is no reason to roll. You don't need to roll to sneak past a corpse (ordinarily) or a person who actually doesn't care if you are there or not (though the GM may call for a roll anyway if you aren't aware of what's actually going on; but failure is irrelevant). Sneaking past absolutely nobody at all, should also probably not require a roll.

Originally Posted by Gollum

Ordinary conversations don't require rolls in GURPS, exactly like driving into town for someone who knows how to drive, or finding the keys of your cars...

Yes, this is the same thing as what I'm saying.

You only need to roll Stealth versus Perception if there is a sentient creature or sensor that can detect you, and will do something as a result of detection. In which case you do need to roll it.

[Gollum]

Originally Posted by sir_pudding

If the person is totally insensate or utterly unconcerned there is no risk, and therefore there is no reason to roll. You don't need to roll to sneak past a corpse (ordinarily) or a person who actually doesn't care if you are there or not (though the GM may call for a roll anyway if you aren't aware of what's actually going on; but failure is irrelevant). Sneaking past absolutely nobody at all, should also probably not require a roll.

Yes, this is the same thing as what I'm saying.

You only need to roll Stealth versus Perception if there is a sentient creature or sensor that can detect you, and will do something as a result of detection. In which case you do need to roll it.

Yes, sorry. I didn't get the meaning of "insensate". I just believed you were talking about someone who don't really pay attention to his surrounding. Someone reading a book, watching the TV, or even sleeping... Brief, a guard who does not his job seriously for instance. Such a guy can still notice the presence of a character who tries to sneak past him... With a lot of luck!

But now that I understand your post better, I fully do agree with you.

[Gollum]

Originally Posted by Anthony

Realistically, hearing is hugely dependent on the quantity of environmental noise, and should change very rapidly from guaranteed detection to no detection (-1 per doubling in range is too small, it should probably be more like -5).

-5 is to harsh, in my humble opinion. I always considered RAW hearing modifiers as written for a situation without environmental noise - and without opposite (or favorable) winds. I consider environmental noise (like big town noise) as a modifier that adds to distance modifiers. But that is just my opinion. If nothing in the rules sounds to say the contrary (as far as I know), nothing confirms it.

[sir_pudding]

Originally Posted by Gollum

Yes, sorry. I didn't get the meaning of "insensate". I just believed you were talking about someone who don't really pay attention to his surrounding. Someone reading a book, watching the TV, or even sleeping... Brief, a guard who does not his job seriously for instance. Such a guy can still notice the presence of a character who tries to sneak past him... With a lot of luck!

But now that I understand your post better, I fully do agree with you.

To clarify, I mean that "specifically on the alert for intruders" makes the most sense, IMO, if you interpret it very liberally to mean "concerned with intruders and unlikely to ignore them if detected". Otherwise you get all kinds of weird puzzles with what "on the alert" actually means. If there's a sentry (even a bored one and even an accidental one), you need to roll a Contest, IMO.

[Anthony]

Originally Posted by Gollum

-5 is to harsh, in my humble opinion.

Well, it would have a rather large bonus. It's basically something like '+1 per 2 dB of noise magnitude; -1 per 2 dB of background noise', so a 50 dB sound with no background noise would be at +25.

[Gollum]

Originally Posted by Anthony

Well, it would have a rather large bonus. It's basically something like '+1 per 2 dB of noise magnitude; -1 per 2 dB of background noise', so a 50 dB sound with no background noise would be at +25.

The problem of such a rule, then, is that it would become clumsy...

• First, it would enforce to know the number of dB of a lot of things. I had to search in the web to know that a normal conversation is about 60 dB. What about a charging big animal like a rhinoceros or an elephant? What about a cat's meow? And what about a gun like an ordinary revolver compared to a sniper rifle? The GM would need a huge list of different sounds...
• Second, it would require a lot of calculations (even if each step would be simple). 60dB without background noise is +30 at 1 yard. The character is 4 yards aways. -10. The effective hearing roll is at +20.
• Third, it would give quite silly results. Someone one yard away shouting as loudly as he can (about 100 dB, -50) with a pneumatic drill around (120 dB, -60) couldn't be heard at all (hearing roll -10). Someone talking to you 4 yards away in a room where there is other conversations couldn't either be heard at all (+ 30 - 30 -10 = -10).

Finally, Vicky asked us to avoid house rules in this thread... So, sorry for the digression. We can go on discussing this rule in another thread or by private message if you wish.

[David Johnston2]

Originally Posted by vicky_molokh

Yes.
Camouflage says that it doesn't provide a bonus to Stealth, which is why the solution seems to be inapplicable.

Camouflage doesn't help people move quietly. Stealth doesn't help people be unseen while standing still. Camouflage would help if you were sneaking up on something that couldn't hear.

This tends to result in weird things like sneaking right next to a character with Stealth 16 almost each and every time, no matter how perceptive said character, as long as said character isn't deliberately standing guard. Which is why the question.

If there's actual cover to work with that isn't a problem.