I wasn't meaning to use fatigue. I was thinking that in your game, your display would would represent the seperate parts of the body. Just gettin the noggin to do some legwork as it were.
I can just imagine now, crawling to a near by health item. almost... there...
Bushido Blade for the PSX handled this quite nicely.
Fallout is a game series that keeps popping up when I talk to people, but somehow I've never gotten around to playing it seriously. I tried out Fallout 3 on a friend's PC once, but I guess the post-apocalyptic world was kind of depressing, and I wasn't a fan of the 50's style.
I've seen their quite detailed targeting system, and that's about as detailed as a game could probably be without going overboard. Didn't really get to play enough to experience injuries. But I agree that realistic portrayal of injuries in a game could lead to boring gameplay, unless your entire goal of a game is to simulate that sort of thing (Robison's Requiem again comes to mind, which was also received as 'boring' by some reviewers).
This just makes me lean more towards just having a 'retry' button, though writing a game in a scifi setting where nano-technology exists certainly gives me a credible explanation for the ability to rapidly heal severe injuries, even mend broken bones. There's still going to be a limit to the healing (nanites need power), so the retry button can't be escaped :P. I wish I could escape it, it just seems like such a cheap copout and a very immersion breaking mechanic. Maybe I'll try to come up with an in-universe explanation (kind of how Borderlands had the New-U stations as an in-universe explanation for resurrection, though that sort of scifi is really soft, and I'd rather have slightly harder scifi)
Kenji, correct me if I'm wrong, but what you described as the health display just sounds like having multiple health bars, but have them overlapping in some manner. I'm not sure I get what you describe. I was actually planning to have the items necessary for healing be put in tough spots, as a means of trying to get the user to use the physics in the game more, so I don't think crawling to them is going to work that well =P
Alpha, I've never owned a PSX, so I can't really comment on that. Care to explain maybe just a little bit how it was handled, and why it was good?
In Bushido Blade, when you fail to parry or dodge an incoming strike, whatever body part that strike hits is incapacitated. Hit in the arm? You're one-armed. Hit then in the other arm? Well, you have no arms (and your opponent will quickly finish you thereafter). A hit in the head, neck, or center of mass was death (iirc). The game had a very steep learning curve but when two players knew both their own chosen weapon and the chosen weapon of their opponent, the duels were really a pleasure to both play in and observe. The game was very, very cool.
I'd assert that the theme of Fallout is just this: being a hero is often a thankless but still worthy job. In so many cases in the games - especially the major story arcs - the main character would choose to do the right thing only to suffer for it, but then the people you'd helped would at least seem grateful and would thrive due to your efforts; that was much of your reward. Fallout 3 added a very interesting reward mechanic, where the radio personality Three Dog would speak about the Lone Wanderer's heroic efforts, as if you were the Batman, or the Lone Ranger, etc. I personally drew a ton of satisfaction from his commentary on the quests I had completed.
I haven't read all of the replies so this might of been mentioned/covered already. I have a similar intention for hp display in my project (A.E.).
Few proposals which tie into what I was planning on doing in my project:
Damage to specific parts affect those specifc parts as well as your health bar.
For example. You said three areas of seperation for now so I would split the effects as follows:
Head = 75-100% hp depletion. Result: critical condition or death/restart of the level (or reset to check point).
Torso/Arms = 25-50% hp depletion. Result from higher end damage to this area: damage caused/accuracy reduced. Damage and accuracy reduced should be based on amount of hp lost from damage to this area.
Legs = 10-30% hp depletion. Result from higher end damage to this area: movement speed and ablility to jump slowed as well as lowered. Both should be reduced according to the amount of damage taken to hp due to this area.
Hope that helps 
Edit: Great comparison/source Thade
Like I said, I've decided to separate just two areas - Torso and Legs - mainly just to have separation of fall damage and bullet damage.
The basic rules about death:
1) If your Torso health drops to 0, you die.
2) If your Legs health drops to 0, you don't die
So, discarding other effects right now, it's Healthbar UI design time!
Stacked Healthbars:
+ Leg / Torso health resolution independent.
+ Leg health falling to 0 does not visually signal 'death' ( case 4 - When legs are broken, healthbar still has overall size )
+ Both Leg and Torso health equally visible (though, is this really a + since Torso health is a bit more important?)
- Hard to tell leg health percentage (since its start is dynamic, based on where Torso health ends)
- Equal in height bars makes figuring out overall health from a single glance
- Worst Fault: Torso Health of 0 is death, but if Leg Health is not yet 0 (or worse, close to full), bar becomes incredibly confusing ( case 7 )
Nested Healthbars (with unequal heights, leg health nested inside torso health bar)
+ Easy to tell how close to death, since overall size of bar = overall health
+ No confusing case at near death
+ Easier to tell health from a quick glance - larger size of Torso bar gives good impression (from color/size) how healthy the player is
- Slightly harder to tell leg health, since it's smaller in height
- Near death, when Torso bar is short, the visual resolution of the Leg Health bar drops, since it scales to a maximum of the Torso width. Result: Being near death makes it harder to tell if you'll survive a fall... is this really a negative? That seems like an odd and unexpected bonus.
Separate Healthbars
[ no picture, because... its easy to visualize i hope ]
+ Independent visual resolution of Torso/Legs
+ Can scale them vertically just as with Nested
+ Simplest, no unexpected side-effects
- Harder to tell at a glance how close to death player is (which healthbar was Legs? Top? Gotta read labels of bars.. oh, I got shot while reading)
- No unexpected bonuses
- No uniqueness (not really that much of a negative, but worth mentioning)
Right now I'm leaning towards using Nested healthbars. Its interesting side effect of making near-death situations even more tense, by making it harder to figure out if player can survive falls, is drawing me towards using it. It's really interesting how a simple UI element like health can have such an impact on gameplay.
Other options I considered: Circular bar, where top half is Torso, bottom half is Legs (seems natural) - has the same advantages as separate healthbars in some way, but also disadvantage that its hard to tell how full the bars are near the top/bottom. Also, circular shape makes it harder to figure out overall health. Sadly, didn't try making one, but I might later when I have more time, just to see what it looks like.
(Emphasis mine.)
How about health indicators based on the sillhouette of a person? This effectively gives you separate bars and makes it immediately obvious which corresponds to upper/lower body. You could have each section fill up like a bar, or indicate damage with shading (eg white->red as you are damaged) and/or a number.
This is more or less precisely what Fallout 3 did; it's very intuitive and easy to tell what the problem is at a glance. Link. Earthsiege and Battletech also do things very similar to this, albeit in a far more detailed way than perhaps you need.
The "stacked bars" idea really doesn't jive with me; it's too cluttered and takes too much brain-processing to peel apart what the issues are...especially when I weight it against other systems I've seen. You want to communicate challenges to your player in as clear and concise a manner as possible: a green body with a red leg very quickly tells me that the red leg is probably hurt somehow, which intuitively explains my slowed movement speed.
