Determining Damage- Realism

[btrc]

Like I said, US Army Medical Service report on combat injuries, WWII and Korea. Also, any medical text on emergency room medicine should have a section on the immediate effects of and treatment of gunshot wounds. The Stockholm International Peace Research Institute (SIPRI) did some stuff that may be of use as well.

Greg Porter
BTRC

[contracycle]

A Name To Know in this regard is Martin L. Fackler.  Stick him in google and you will find some articles.  Other search terms would be: 'wound ballistics' and 'terminal ballistics'.  There is apparently a lot of controversy, but sometimes I suspect this is more smoke than fire.  Little of this is actual statistical analysis because a well recorded fight is a rare thing.

I agree with Raviens tho; with this much attention to injury, the system is encouraging peoiple to fight, else they have no use for the system.  So whatever you decide, you should operate on the assumption that a large proportion of the actual in-game resolution will be combat related and plan accordingly.

[daMoose_Neo]

Question:
Given that
1) You have an extensive background as a war-gamer
2) Your playtesters are, by your statement, possibly more into war-gaming than RP'ing
3) The system in question is focusing on 'realism' and a high level of precision in emulating the real world, leaving some room for 'margin of error' type occurances.

Do you have any actual play you can post?
Concurring with the above, that a lot of the mechanics are gearing toward combat, I'm wondering if this is more a war/mini's game without precisely created terrain and minis.
Just a personal opinion, but role playing means more storytelling to me. Pitch the physics- if it makes a good story, I'm for it :D But thats just me.

[Dauntless]

Thanks Greg and contracycle.  Once I'm done with one of my school projects, I'll do some more research on this.

As for a play by play account of how my system works, I'm getting there, but there's still a few things that I haven't fully worked out yet.  The main one being the Sequencing system I use.  I also have to do more work on the statistical chances of actually hitting anyone.  Right now, I want to make my system's ease of hitting someone fairly hard to do unless they have a good amount of time to aim and both the shooter and target are relatively stationary.

Actually, the first and second points go hand in hand with each other.  The more time you spend aiming, the longer it takes for you to pull off your shot, but then you have a better chance of hitting.  The downside is that you're vulnerable, the other guy may hit you first if he pulls off a snap shot, and even if he misses he might make you flinch.  I'm still trying to decide if I should use a count-up sequencing system like Phoenix Command used (where the Action Cost of doing a task depends on the character's speed) or a count-down system, similar to the first edition Shadowrun where you roll an initiative amount, and then count down (and if someone reaches 0, they get to add their speed score again to refresh the initiative pool).  They basically both work the same, but the hard part is calculating Action Costs for various tasks, and then modifying this by the character's speed (the faster you are, the shorter it should take you to do something).  If I make it such that higher speed characters only have higher initiative pools, it means that they can perform more actions per round, but they won't be faster than a slower character who is performing the same task...so I'm not sure how to tackle this other than factor the character's speed into the Action Cost.

Hopefully I'll have a prototype game engine up within the next month or two (as school permits) and then start tweaking by playtesting it from there.

As for how much roleplaying there will be in the game?  Hopefully about a 50/50 mix of gaming and roleplaying.  I think they both can bounce off the other.  For the experience I'm trying to get across, I think combat is best left to having detailed tactical choices.  Roleplaying (or narratively describing combat) the combat scenes just isn't my cup of tea.  I tend to prefer things to be a bit more objective than the more narrative (I don't mean this necessarily in the GNS sense) combat resolution systems.  In my system, you still have to describe in intimate detail what you are doing and how you are doing it, but these choices are objectively quantified.

For me, the roleplaying will come from the setting.  I have two preliminary settings in mind.  The first will be a pseudo-historical pan-asian setting.  If you can imagine that the eastern nations didn't encounter any European nations until about the 1860's-1900's timeframe, you'll get an idea.  The theme of the game will be about the loss of a way of life, and it will highly stress the philosophical and mystical aspects of the many martial and philosophical orders of asia.  The martial arts will be realistic, though bordering on the paranormal (imagine if it was not uncommon to find warriors as good as Bruce Lee, Morihei Ueshiba, Mas Oyama, or Sokaku Takeda).  There will absolutely be no wire-fu, no mystical flame bolts, no glowing 6' swords, and no steam punk Edwardiana/Victoriana.  But it will be about having to find a way of life swallowed up by a growing insidious industrial and mechanistic power.  So the setting will not just have combat, but also intrigue as well as diplomacy attempts to reconcile the eastern and western powers.

The other setting will be a transhumanistic, pre-singularity near future timeline (about 2050-2075AD).  The world suffered through a 3rd World War in the 2040's between what we would consider the 1st world countries today, and what would be considered 2nd and 3rd world countries (China, India, all of South America and Africa except S. Africa).  The war was fought over the right to research and develop certain key technologies (the dangerous ones) which the 1st world nations forbade.  Because the 3rd world countries refused, they used these technologies to gain an equal economic footing with the rest of the developed world.  Much of the world is now pretty much fully developed, or at least more developed than it was at the turn of the millenium.  But the war was never fully resolved to the satisfaction of either parties, and there has been a low key cold war going on ever since.  The threat of the proliferation of the GNI technologies (Genetics, Nanotechnology, Intelligence) has created a new form of arms race.  Ironically, the former 1st world countries are now forming Luddite movements to actually try to stop some technological progress, as they fear the new transhumanist and extopian movements which have swept over the world.

So this setting is really about player choice.  What side do they represent?  Are they Luddites or Transhumanists?  Are they artificial lifeforms suffering racism?  Where to do the players stand on the creation of artifical humans or artificial intelligence?  There is combat in this universe, but ironically, it's harder to "die" in this setting too.  In fact, it's because of the almost superhuman nature of some of the characters in this game that I'm most worried about determining damage.  If I can figure out the baseline damage for a normal human, then hopefully I can extrapolate out what androids, or genegineered and nanite enahanced humans could withstand.

[Dauntless]

Thanks Greg and contracycle.  Once I'm done with one of my school projects, I'll do some more research on this.

As for a play by play account of how my system works, I'm getting there, but there's still a few things that I haven't fully worked out yet.  The main one being the Sequencing system I use.  I also have to do more work on the statistical chances of actually hitting anyone.  Right now, I want to make my system's ease of hitting someone fairly hard to do unless they have a good amount of time to aim and both the shooter and target are relatively stationary.

Actually, the first and second points go hand in hand with each other.  The more time you spend aiming, the longer it takes for you to pull off your shot, but then you have a better chance of hitting.  The downside is that you're vulnerable, the other guy may hit you first if he pulls off a snap shot, and even if he misses he might make you flinch.  I'm still trying to decide if I should use a count-up sequencing system like Phoenix Command used (where the Action Cost of doing a task depends on the character's speed) or a count-down system, similar to the first edition Shadowrun where you roll an initiative amount, and then count down (and if someone reaches 0, they get to add their speed score again to refresh the initiative pool).  They basically both work the same, but the hard part is calculating Action Costs for various tasks, and then modifying this by the character's speed (the faster you are, the shorter it should take you to do something).  If I make it such that higher speed characters only have higher initiative pools, it means that they can perform more actions per round, but they won't be faster than a slower character who is performing the same task...so I'm not sure how to tackle this other than factor the character's speed into the Action Cost.

Hopefully I'll have a prototype game engine up within the next month or two (as school permits) and then start tweaking by playtesting it from there.

As for how much roleplaying there will be in the game?  Hopefully about a 50/50 mix of gaming and roleplaying.  I think they both can bounce off the other.  For the experience I'm trying to get across, I think combat is best left to having detailed tactical choices.  Roleplaying (or narratively describing combat) the combat scenes just isn't my cup of tea.  I tend to prefer things to be a bit more objective than the more narrative (I don't mean this necessarily in the GNS sense) combat resolution systems.  In my system, you still have to describe in intimate detail what you are doing and how you are doing it, but these choices are objectively quantified.

For me, the roleplaying will come from the setting.  I have two preliminary settings in mind.  The first will be a pseudo-historical pan-asian setting.  If you can imagine that the eastern nations didn't encounter any European nations until about the 1860's-1900's timeframe, you'll get an idea.  The theme of the game will be about the loss of a way of life, and it will highly stress the philosophical and mystical aspects of the many martial and philosophical orders of asia.  The martial arts will be realistic, though bordering on the paranormal (imagine if it was not uncommon to find warriors as good as Bruce Lee, Morihei Ueshiba, Mas Oyama, or Sokaku Takeda).  There will absolutely be no wire-fu, no mystical flame bolts, no glowing 6' swords, and no steam punk Edwardiana/Victoriana.  But it will be about having to find a way of life swallowed up by a growing insidious industrial and mechanistic power.  So the setting will not just have combat, but also intrigue as well as diplomacy attempts to reconcile the eastern and western powers.

The other setting will be a transhumanistic, pre-singularity near future timeline (about 2050-2075AD).  The world suffered through a 3rd World War in the 2040's between what we would consider the 1st world countries today, and what would be considered 2nd and 3rd world countries (China, India, all of South America and Africa except S. Africa).  The war was fought over the right to research and develop certain key technologies (the dangerous ones) which the 1st world nations forbade.  Because the 3rd world countries refused, they used these technologies to gain an equal economic footing with the rest of the developed world.  Much of the world is now pretty much fully developed, or at least more developed than it was at the turn of the millenium.  But the war was never fully resolved to the satisfaction of either parties, and there has been a low key cold war going on ever since.  The threat of the proliferation of the GNI technologies (Genetics, Nanotechnology, Intelligence) has created a new form of arms race.  Ironically, the former 1st world countries are now forming Luddite movements to actually try to stop some technological progress, as they fear the new transhumanist and extopian movements which have swept over the world.

So this setting is really about player choice.  What side do they represent?  Are they Luddites or Transhumanists?  Are they artificial lifeforms suffering racism?  Where to do the players stand on the creation of artifical humans or artificial intelligence?  There is combat in this universe, but ironically, it's harder to "die" in this setting too.  In fact, it's because of the almost superhuman nature of some of the characters in this game that I'm most worried about determining damage.  If I can figure out the baseline damage for a normal human, then hopefully I can extrapolate out what androids, or genegineered and nanite enahanced humans could withstand.

[Valamir]

Wow, Dauntless...

Both of your settings sound intrigueing.

But I can't for the life of me even conceive how game play in either of them will be enhanced by a combat system that takes into account bullet tumbling.

I mean, I had assumed when you started discussing the nitty gritty of ballistic weaponry that your game was going to be about PCs as members of a SWAT team, or a commando unit, or a unit of soldiers ala Band of Brothers.

A game about "having to find a way of life swallowed up by a growing insidious industrial and mechanistic power." sounds pretty cool.

What fer schlitz do you need to worry about modeling ballistic effects for to play that game?

Seems like a dramatically misplaced priority.  My first concern would be how to structure the key attributes and mechanics of the game to focus on the issue of individuality vs. mass produced culture; tradition vs. progress and other key setting elements.

The last thing I'd worry about in a setting like that is detailed trauma mechanics for getting shot.  I have to say, that seems entirely...pointless.

[btrc]

As for a play by play account of how my system works, I'm getting there, but there's still a few things that I haven't fully worked out yet.  The main one being the Sequencing system I use.  I also have to do more work on the statistical chances of actually hitting anyone.  Right now, I want to make my system's ease of hitting someone fairly hard to do unless they have a good amount of time to aim and both the shooter and target are relatively stationary.

I believe that for any combination of non-range modifiers, when you plot it against range, the chance to hit will look like the right hand side of a bell curve. What will vary will be the Y maximum of the bell curve (chance to hit at 0 range) and the steepness of the dropoff to insignificant percentages as range increases.

Much easier said than done, but if you want "realism", that's what you should shoot for (no pun intended).

Greg Porter

[daMoose_Neo]

If you can pull the role playing in from the setting, most excellent.
Just looking at how you're setting everything up, with the attention to detail and realism and algorithims, concerned it would become nothing more than a war game without minis.
Thats what I said about "breaking character"- having to stop being the character to calculate the damage, trajectory etc etc There is a certain amount of that in any game, granted, but I'd think you'd want to keep more of that to a minimum to keep it from becoming a war game or a board game.
Detail is a good thing, but just saying for a "role playing game" you'd want to keep the math and calculating players have to do to a minimum so they can focus on the character, setting, and events at hand.

[Dauntless]

Strange, I had created a followup post, but instead the first got double posted and the followup didn't get posted at all....oh well...

In my second post I had conceded that in many ways my game is something of a wargame in disguise.  While it's possible to do combat without minis and a map, it'll definitely be easier.  It's also developed the way it has because I'm going to transport and modify many of the rules I create for this game into a computer game engine (which I call STRIKE, for Strategic Tactical and Roleplaying Integrated Kit Engine).  The Kits are various plug-ings which supplement the Core rules (in fact, which are necessary to play in certain genres).

So while my two settings may seem far removed from modern day gun combat, the Transhuman setting will need to cover firearm combat in great detail, and I also wanted players to be able to create their own settings.  The game system is only going to be semi-universal however.  There are Core Rules, there are Plug-ins, and there are the World books.  Technically the World books are optional, as these will have world detail as well as the Lifepath Templates of the various socio-economic-cultural-caste stereotypes.  There will be rules to cover the creation of new Lifepath Templates, but the World books will cover them in detail.

If I ever finish the first two World books, my third is going to go back to Vietnam in which case I'll definitely need the Terminal Ballistics data.

I hope the roleplaying is inspired from the settings.  They are both somewhat niche settings, but ones which nevertheless offer alot of insight into the human psyche.  It may seem that with my relentless pursuit of getting the numbers right that I'm losing sight of the human element.  One of my goals with the game design is to get the players truly fearful of combat, because I think it's used too often.  There will be many times where combat is unavoidable, but I want the players to never take combat for granted.  In my martial arts system plug-in, I also wanted to do justice to the philosophical and mystical aspects of the arts to get away from the Technique-Fu of other games.  If I can pull off the feeling of Katsujinken (the life giving sword, as opposed to satsujinken, the life taking sword), then I'll have accomplished my goal.

[Dauntless]

BTRC-
For me, the tricky part about figuring out the statistics of shooting is dealing with the range aspect.  The farther away a target is, the smaller the target appears, so in a way, it's about target size.  But it's even more difficult because now you have to take into account the round trajectory.  Most modern weapons fire on the order of 1000m+/sec, so lead times aren't going to be that bad really.  Not to mention that most firefights even out in desert zones take place at less than 700m.  Even at a relatively far range of 100m, a weapon with a muzzle velocity of 1000m/sec will get there in a little over 1/10th of a second (the bullet slows down due to drag).  That means the bullet drops due to gravity only about 9.8m/sec sq*(.1sec)^2 = .098m, or about 4" give or take a little.  Combine this with bad winds, and the weapon's inherent accuracy though, and it can come out quite a bit more...enough to make the shooter miss the target if he didn't make any corrections.

I'm also trying to account for what I call the Delta Theta.  The Delta Theta is the change in angle the shooter has to make to keep the weapon trained on the target over a certain amount of time.  Very large Deltas and very small Deltas are hard to do.  For example, let's say that the target is only 10m away, but is running very fast, say about 8m/s perpendicular to you (at a 90 degree angle).  You can do some fairly simple Calculus to determine the rate of change of Delta Theta with respect to time.  The much more intuitive idea is simply this....a target moving at right angles to you requires a greater Delta Theta than a target that's moving directly toward you or away from you.  In other words, target speed andtarget direction (his vector) are important.  On the flip side, the farther away a target is, the more minute the Delta Theta becomes.  At ranges past 300m, changing the angle 1minute of 1 degree could mean the difference between hitting or missing.

Finally, I have to consider the whole fear and confusion factor.  It's one thing to shoot at a non-moving target on a firing range, and quite another to accurately shoot while that target is shooting back.  It's been said that the best gunslingers of the west weren't always the fastest or the most accurate, just the ones who controlled their fear the best.

Actually, I'll probably start a thread on this subject in a little bit since it deserves its own thread.

[btrc]

Dauntless,
You're doing it from the wrong direction (add exclamation points to taste). Increased shooter skill means increased ability to do those calculations intuitively and on the fly, just like an outfielder can figure the trajectory of a ball and intersect where it is going to land, even though they are themselves moving while they figure it out and mentally keeping track of their position compared to where they want to throw the ball once they get it.

You simply need to set your range and movement modifiers so they give plausible results for most modern weapons (since you will have no lightspeed weapons). If you have a weapon with exceptionally good or poor range characteristics, you factor that into the weapon's stats as a fixed quantity.

I have no combat experience, but if I pick up a rifle of a given caliber, I know that if it is sighted in level at 100 meters, about how much to compensate vertically for any useful range on that weapon, and how much to lead on a stationary or walking target. This comes from my (passable) skill level.

And I know not to shoot at a running deer at most ranges because I'll probably not hit my aim point, and would rather not have a wounded animal to track down. Knowing when -not- to shoot also comes from my skill level (an intuitive feel of my success chance).

Come up with a few curves that you are confident with, and then work the skill and modifier system to match the curves. I'm a numbers geek, but -trust me-, few roleplayers want to spend 15 minutes figuring out MOA dispersion at 231 meters range with air density at 2,300 meters altitude with a 7 meter crosswind and 5 degree inclination.

At a certain point, your accumulated error exceeds the accuracy gained by each extra step.

Greg Porter

[MarktheAnimator]

I need the hard data based on real world data so that I can make a more simplified, yet hopefully still somewhat accurate and consistent model.

I wish I coud find some military/police data on wounds. If it seems like the caliber of a round is largely independent of how incapacitating a wound is, then I'll account for that in how I determine damage. It's this sort of statistical data I'm looking for to help me figure out how to calculate damage. Do any of you have links or books sa suggestions I could read?

Hello,
My dad is a ballistics expert and gunsmith.  
So I've been listening to him talk about this stuff for years.

Translating real world experiences into a game is difficult.....

With firearms, there are two issues:
1. Stopping Power.  The percentage chance of dropping your opponent with one shot to the chest.

2. Killing Power.  The chance of killing your opponent.

Mostly, people are concerned with stopping power.

My dad says that many people have different oppinions about stopping power, but what he mostly refers to is a study done by Evan Marshall & Ed Sanow on real world results of shootouts by the police.  
Here is a link:
http://www.firearmstactical.com/marshall-sanow-statistical-analysis.htm


In case you're interested in the history of the stopping power debate, here are a few links:
Elmer Keith:  http://www.darkcanyon.net/elmer_keith.htm
Chuck Taylor:  http://www.chucktaylorasaa.com/stoppingpower.html

Here is an article on the Power Index Rating system, which was used to determine stopping power:
http://www.freerepublic.com/focus/news/849728/posts


Killing Power is another subject.
Getting shot with a .22 can sometimes be more dangerous than getting hit with a bigger bullet because the doctors may have trouble finding the bullet.  I've heard that many assassins use .22 rounds.

Of course, if your chest is missing, the chance of recovery is also low. :)


So using a system of damage in a game is tricky.

I haven't done a modern game yet (I'm still finishing my fantasy game), but when I do, I plan on including these elements:

1.  Stopping Power.  A percentage rating listed for the ammunition used.
2.  Killing Power.  The chance of killing your opponent.
3.  Penetration.  How far the bullet will penetrate.  
4.  Dependability.  Is the weapon going to jam?  The M-16 is a terrible weapon compared to the AK in this regard.  The marines didn't want to give up their M-1's because they had more accuracy and were more dependable.
5.  Accuracy.  How accurate is the weapon?
6.  Ammunition types.  Stopping power, penetration, dependability, etc. change drastically depending on the specific ammunition type used.


Stopping power is mostly a debate centered around handguns.
Hydrostatic Shock is caused by bullets faster than 2000fps, so rifles will stop most people.

However, there are also cases of people getting their entire chests blown out and they continued to fight for several seconds afterwards!
Perhaps 10% of the time.

So I'd include a chance of the opponent continuing to fight no matter where he is hit (except the spine or head which will stop them instantly).



So I hope that helps.  Then again, maybe I've made it more difficult. :)

..

[btrc]

Was working on one of my own projects, and stumbled across this site:

http://www.firearmstactical.com/tactical.htm

Might have some useful links.

Greg Porter
BTRC