I was working on my game yesterday and was deciding what mechanics to use for a nocturnal race with very night-adapted vision.  I checked how I had handled modifiers for lighting in the rest of the system and found seven different methods, which is no good at all. Time to write a unified mechanic.   The goal for the system is simple mechanics, lots of modifiers you can try to make happen to influence your checks, and fairly realistic.  So I'm shooting for lowish-crunch, though medium crunch might be the best I can attain.  I would like some opinions

I definitely need rules for darkness and blindness, but what about low light conditions?  I've spent enough time out in the woods at night to know that melee or missile combat in darkness, starlight, moonlight, twilight, and daylight are all going to be significantly different.  But is it going to be worth the trouble, both in writing the game and time at the table?  This also applies to things like tracking, climbing, etc.  If anyone has experience with game that deal with this issue, I would particularly like to hear from you.

Does fighting in darkness favor the attacker and defender?  I would guess the attacker, because he only has to guess where a large relatively slow body is while the attacker has to try to block a smaller faster weapon, but I dunno.  I haven't actually done it.  If both combatants are attacking and defending I would guess the effect is that hits are going be rarer but do more damage, and skill would be less important.  On this question I'm really not interested in what other games have done, but instead in actual experience.

Also, has anyone seen a good reference on sight range in various lighting conditions?  I found surprisingly little on the internet.

Quote from: Mishihari on January 19, 2021, 05:44:49 PM
I've spent enough time out in the woods at night to know that melee or missile combat in darkness, starlight, moonlight, twilight, and daylight are all going to be significantly different.  But is it going to be worth the trouble, both in writing the game and time at the table?  This also applies to things like tracking, climbing, etc.  If anyone has experience with game that deal with this issue, I would particularly like to hear from you.

I suggest that you consider the different light conditions in terms of crunch, rather than in terms of real world. Real-world emulation is fun, but doesn't typically result in "lowish" crunch. So the question I would ask is: how many light divisions do you want the game to have, regardless of real life? What is "low to medium" crunch in that regard to you? This is what I think will best drive your design.

For myself, "dark" and "low-light" are the most crunch I would want in a low-crunch game, where "low light" is half the penalty of complete darkness. If you feel the need to be more specific than that while still keeping the game rules-light, remember that such adjustments can always be made at the table as well, even if they aren't codified in the rules. If the rules only specify "dark" as -4 and "low light" as -2, nothing stops you from imposing a -3 penalty in starlight, at the table. That is, the rules can be enough to inform "crunchier" decision-making, without themselves being crunchier.

Regarding who has the advantage; if they are Human, the Defender should benefit from darkness/concealment in combat.

Maybe not for approach or surprise, but when actually attacking.

Take the real world for an example (since that is what you cited); would you rather someone be firing a bow at you in the middle of the day, or in the middle of the night?

Quote from: Two Crows on January 20, 2021, 12:08:31 PM
Regarding who has the advantage; if they are Human, the Defender should benefit from darkness/concealment in combat.

Maybe not for approach or surprise, but when actually attacking.

Take the real world for an example (since that is what you cited); would you rather someone be firing a bow at you in the middle of the day, or in the middle of the night?

Agree for ranged, disagree for melee.  As long as you know the general area to swing in, you're going to hit something.  Would you rather try to parry a sword swing in the middle of the day, or in the middle of the night? 

Quote from: Eirikrautha on January 20, 2021, 01:33:45 PM
Agree for ranged, disagree for melee.  As long as you know the general area to swing in, you're going to hit something.  Would you rather try to parry a sword swing in the middle of the day, or in the middle of the night? 

I can't answer for the real life part.  I assume that someone that is fighting at night on purpose is doing so because they have some advantage (or think they do) which will involve more than just sword ability.  That huge caveat aside:  If the only question is my skill relative to the opponent's skill, then I want to fight at night when they are better than me and in the day otherwise.  Because any environmental condition you throw in that makes things more difficult favors the person with less overall ability.  Or perhaps more clearly, it hurts the person with less ability less because they have less ability to be nullified by the conditions, making their relative chances better.

Again, though, if I'm Mr. Beginner with  the sword going up against Dr. Expert with the sword, then I don't think it matters, because chances are he didn't get to to be the expert without dealing with environmental conditions already--and that experience is going to be telling.

Quote from: Mishihari on January 19, 2021, 05:44:49 PMAlso, has anyone seen a good reference on sight range in various lighting conditions?  I found surprisingly little on the internet.

When I was a kid, my family went to Mammoth Cave in Kentucky. During the tour, in a particularly large chamber, the guide had us turn our flashlights off and wait a few minutes. I was so dark that you literally couldn't see your hand in front of your face. Then the guide lit a single match and with just that much light, I could see the entire room and almost every person in the room. I had already started playing D&D at that point so the experience impressed me.

Also, I know from camping that on a moon lit night, you can see very far away. Details are lacking but you can see roads, trails, people, buildings, etc. There is no "range" for viewing.


All that being said, I think that most games get their torch and light rules backwards. Instead of a torch letting a person see 30 feet away, it should be that anyone within 30 feet of a torch can be seen by anyone else at any distance away. It should be next to impossible for a party of adventurers carrying a torch to surprise any monster in a dungeon as the light can be seen from far away, around corners, and even in tiny gaps under a door.

Quote from: hedgehobbit on January 20, 2021, 02:51:35 PM
All that being said, I think that most games get their torch and light rules backwards. Instead of a torch letting a person see 30 feet away, it should be that anyone within 30 feet of a torch can be seen by anyone else at any distance away. It should be next to impossible for a party of adventurers carrying a torch to surprise any monster in a dungeon as the light can be seen from far away, around corners, and even in tiny gaps under a door.

While researching that topic, I found a short Youtube video series about torches, https://youtube.com/playlist?list=PLDIGNPoKkW_K0MHfq_H9SjE0XixyjM3ON, that made this point and some related ones.

Quote from: Zalman on January 20, 2021, 10:25:32 AM

I suggest that you consider the different light conditions in terms of crunch, rather than in terms of real world. Real-world emulation is fun, but doesn't typically result in "lowish" crunch. So the question I would ask is: how many light divisions do you want the game to have, regardless of real life? What is "low to medium" crunch in that regard to you? This is what I think will best drive your design.

This struck me as really good advice, so I tried to follow it and discovered that I don't trust my own judgment as to what is "rules light."  I've professionally written engineering design documents and business plans, and my first draft work for games often has a similar level of complexity.  So I thought I'd explain the second draft of the rules here, and maybe someone with better insight can tell me if they're finicky or not.

========

The GM decides the visibility, which can be good, moderate, poor, or none.  The GM can just pick one if he wishes, or use a slightly more elaborate method where light levels from "pitch black" to "full sun" map onto visibility and may be adjusted by a few factors such as "viewer in brighter light than target" and "eyes not adjusted."  E.g. if it's twilight with a heavy rain, then twilight maps onto moderate visibility, and the rain shifts it one step to poor.

On the player side, skill checks for actions where vision is relevant are modified by 0, -2, -5, and -10 for good, moderate, poor, and none, respectively.  Certain actions are adjusted because the lack of visibility doesn't affect them quite as much.  Melee attack is adjusted by one step, e.g. if the mod is -10, then it moves to -5 instead, and melee defense is unadjusted.

========

As just a bit of perspective on the game, skill checks are talent+skill+d6+modifiers, either against a target number or opposed.  My goal with this is to have skill and talent have the greatest impact on success, then modifiers, then the random element.  I would have preferred a simpler system, but stealth is pretty important in the game, so I decided a bit of resolution would be useful.

Quote from: Steven Mitchell on January 20, 2021, 01:59:17 PM
I can't answer for the real life part.  I assume that someone that is fighting at night on purpose is doing so because they have some advantage (or think they do) which will involve more than just sword ability.

While using visibility for advantage is certainly a tactic, and there's a lot of that built into the rules, it's pretty easy to see who has the advantage.  But sometimes stuff happens and you don't have a choice.  Frex your enemy's club hits your lantern and now you're both in the dark.  That's the case I was struggling with.

Quote from: hedgehobbit on January 20, 2021, 02:51:35 PM

Quote from: Mishihari on January 19, 2021, 05:44:49 PMAlso, has anyone seen a good reference on sight range in various lighting conditions?  I found surprisingly little on the internet.

When I was a kid, my family went to Mammoth Cave in Kentucky. During the tour, in a particularly large chamber, the guide had us turn our flashlights off and wait a few minutes. I was so dark that you literally couldn't see your hand in front of your face. Then the guide lit a single match and with just that much light, I could see the entire room and almost every person in the room. I had already started playing D&D at that point so the experience impressed me.

Also, I know from camping that on a moon lit night, you can see very far away. Details are lacking but you can see roads, trails, people, buildings, etc. There is no "range" for viewing.


All that being said, I think that most games get their torch and light rules backwards. Instead of a torch letting a person see 30 feet away, it should be that anyone within 30 feet of a torch can be seen by anyone else at any distance away. It should be next to impossible for a party of adventurers carrying a torch to surprise any monster in a dungeon as the light can be seen from far away, around corners, and even in tiny gaps under a door.

I've done the Mammoth Caves thing too.  I had my own striking experience a few months ago that partially motivated  this.  I was throwing a football with my son, the sun went down, and at a certain point I suddenly couldn't catch the ball anymore!  I could see everything pretty well, but my eyes couldn't track a fast-moving ball in dim light.  It was really weird, and it seemed like something that would make melee defense a whole lot harder.

I've done a fair amount of hiking and camping at night as well, and it seems complicated.  There's a big, big difference between full moon, starlight, and pitch dark.  I was recently hiking in the woods when the sun went down.  In daylight visibility was about 50 yards; in the dark with a flashlight it was more like 20.  I found this article:

http://www.mkrgeo-blog.com/the-role-of-contrast-in-ability-of-human-vision/#:~:text=These%20elements%20are%20very%20important%20because%20explain%20the,object%20distinguishable%20from%20its%20background%20or%20another%20object..

and did some math to get the result that an unilluminated white circle two feet across is visible at about a mile in late twilight, dropping to about 3500 ft in dim moonlight and 1400 ft in starlight.  This would be great if our enemies werewhite circles, but it's more complicated and I'm not that confident that I did the math right.  I would still love to get a table of real experimental data by someone who knew what they were doing.  It seems like the type of things that would show up in military manuals, but half my search results on the topic seem to be RPG rules, which isn't exactly what I'm looking for.

Quote from: Mishihari on January 26, 2021, 05:56:09 AM
I've done the Mammoth Caves thing too.  I had my own striking experience a few months ago that partially motivated  this.  I was throwing a football with my son, the sun went down, and at a certain point I suddenly couldn't catch the ball anymore!  I could see everything pretty well, but my eyes couldn't track a fast-moving ball in dim light.  It was really weird, and it seemed like something that would make melee defense a whole lot harder.

It would.  But ranged defense would be even worse.  At least with melee, in partial light you are still picking up clues from the body position of your opponent.  You have some general idea of where the melee weapon is.  With an incoming javelin, good luck with that.  Maybe a spinning hand axe wouldn't be much worse than melee.

I have depth perception issues thanks to an odd eye condition.  When my prescription is corrected, I can manage ok.  Not good, but nighttime doesn't seem to diminish much compared to what other people experience.  Let the prescription get off and suddenly something like driving at night is extremely risky.  Point being, in reality there a host of factors your brain is processing rapidly to adjust. 

In fencing, the tip of a foil or an epee, in even moderately trained hands, moves faster than the human eye can track.  Your opponent can't track it.  The official judging the match can't.  You can't even do it, knowing where you plan to put it.  That's in good light, no rain, no environmental conditions at all.  Now sure, most melee weapons don't move that fast.  They can still move pretty darn fast and you have those less than perfect conditions to consider.  What isn't moving nearly as fast is the opponents arm, hand, and the rest of the weapon that isn't the business end.  If you can see that, you are picking up a lot of information. 

Also consider, all else being equal, I'd rather fight one opponent at night than two opponents in the light.    One of the reasons is that all of that extra information you are picking up is harder to process and less useful at times when you have multiple opponents.