If you guys have ever played the original Deus Ex, it had a system of damage done per body part - left/right arm, left/right leg, torso and head.
Most games only have the typical single health bar (excluding the huge exception of Dwarf Fortress, and a couple of other ones, like the old Robinson's Requiem come to mind).

I'm obvious downside is that it increases complexity of the game - the health can't be represented in a nice red bar, or a few digits on the UI. There's also no easy way to tell if you'll die soon - depending on how 'death' is considered. It's possible that, for example, all your body is in perfect shape, but your head is down to almost no health, so one critical hit and you're dead.

On the upside, it's a nice separation of damage. I'm currently working on a 2d platformer, and right now have health as a single healthbar, and all I have right now is fall damage. But thinking ahead, I am going to have enemies that shoot at you - and it seems like it might be a good idea to have some separation of health so the player can take both projectile damage and fall damage without them stacking (projectiles hitting mostly the torso, with some chance for legs and a smaller chance for head, while fall damage being entirely on legs).

I was thinking of a simpler separation, just three areas - head, torso/arms and legs. My thoughts were that if your head or torso run out of health, you die and have to retry. But it doesn't make sense that you would die if your legs get broken by a high fall.

It would make sense that if your legs are low on health, i would force the player into a crawl mode, but this presents a problem, since it's a platformer game, and not having the ability to jump might essentially get the player stuck in some spot without a way out.

So, I'm wondering two things:
1) is it worth implementing a system beyond just a simple health bar
2) What do I do when the legs are damaged? How can I account for the possibility of the player being stuck in that case? A simple reset button?

Some input in general on healthbar vs detailed health, or input on my specific issue is appreciated.

I think this would add some interesting dynamic to the game. Although as you say it increases the complexity of the game tremendously. The head, torso and legs separation seems like a good balance point though. But it really depends on the game design, breaking your legs is game over in a platformer if you don't have some interesting mechanics when that happens.

Maybe the player would need to defend him/herself from enemies while not being able to move when having broken legs for a while, and having the leg health automaticly regenerate.

You could also get different disadvantages depending on where you're hurt. Lets say there's three damage stages:

Normal - Everything functions as intended.

Hurt - There are some disadvantages. If your head is hurt maybe you have decreased vision, are confused etc.

"Dead" - Torso and head damage here would be fatal but damage to the legs may result in the scenario I described above.

Addressing both posts above:

Not sure about leg health auto-regeneration. I have plans for an item that can be used to heal, but the problem is still that you can only have a limited max number of them (small number, like 10). Maybe a 'Restart Level' button is appropriate if it is only necessary when the player is out of the healing items,

I do like having some sort of effect depending on health. I'm not really planning a combat game, so it's possible to actually disallow any sort of shooting by the player if the head is damaged. By possible i mean it should hopefully not have a major impact on gameplay, other than increased difficulty.

The zone division is really only going to be concern for the player being hit by enemies, not the other way around.

As I said above, it's not going to be a shooter-focused game. The player will be able to aim, but the weapons used by the player are not actually going to be normal projectiles. (basically there are only 2 player weapons, an electric gun and a knockout-gun, both of which have very little and limited ammunition. Essentially the limitations on weapons are there to force the player to NOT go through a map shooting everything in sight, but to be more of a just-in-case.. but I get off topic)

Dying when leg health drops to 0 might be an option, but since healing is present a Restart button might be a better idea. However, I do agree that falls from great heights should kill the player. Well, not necessarily heights, but collision speeds - but yes, I think I need to account for that too.

That's another part of abandoning the simple health bar - the situations I need to account for, code-wise, starts growing.

On second thought, I might just separate the areas into just two - lower and upper body - to reduce unnecessary complexity even further.

In DnD when you are using unarmed combat, your character deals fatigue damage. If your fatigue damage is equal to or greater than your health then your character passes out.

I would invision this as single health bar with an off color, opaque overlay in a different color. Something like that would still be a single bar with the benefit of the seperation.

You could set up the levels in such a way that you can get all sorts of sweet cool stuff and upgrades and all that whatnot. Add in a grapple hook you could do all sorts of complicated moves to get said stuff. If your legs are busted you still *could* complete the level but you'll miss out on the loot.

Something to get ideas flowing. :D

I spose it depends on the damage types in the game but if it were me, I'd separate the limbs, torso and head then create animation for damage (both in receiving damage and displaying the type of damage taken) for example, limb and torso damage effects different controls and creates dead arm, limping or doubled over animation. As you indicated head damage would effect senses, vision, sound or lose control of certain movement. Its worth the extra animation, since this visual indication connects the player to the game character immersing the player with empathy instead of data analysis.

Kenji:

I'm not sure how fatigue would apply to my game, since I have no plans of introducing fatigue in it. It doesn't seem fitting for a more constantly-on-the-move game, whereas in an RPG where you can potentially do things like rest/sleep, visit inns, or just walk around and talk with people, a fatigue system seems more at home. As much as I like RPGs, I'm not making something like that.

Oddly though I had 'grapple hook' as a mechanic on my "feature creep" section of tasks. I think I dropped it because I really want to keep the game as simple as possible and dealing with the physics while using a grapple hook isn't really something I want to do (physics, as in not just swinging, but collision with different tiles). In any case, it's not an option for me to consider how to handle broken legs.

There's also no 'loot' in the game, and the challenges are focused pretty much on completing the levels (so far). This is getting off topic though.

Mratthew:

There's really going to be only two sources of damage to the player (well, there's one instant-kill thing, but that's not 'damage') - fall damage and bullet damage. The game is also a 2d side-scrolling game, which is the main reason I was looking to minimize the separation of areas. Of course, a bullet hitting the player can just roll a random number to indicate where it hits, which would allow for complete limb separation (left arm, right arm, etc.), but I am not convinced that there's any benefit to that much detail.

My current thoughts are to have only two areas: Upper body and Lower body.

I definitely like the idea of animation/effects indicating the health, and dropping the UI elements. However, let's take the case for lower body:

I don't want minor fall damage to affect your running/jumping capabilities. So, if leg health is above, say, 50%, there shouldn't be any animation differences or speed difference. Without indicators, the functionality at 51% and at 100% will be visually and physically indistinguishable. So it would make it hard for the player to realize if they can heal their legs further (if they're at 51%) or if healing won't have an additional benefit (if they're at 100%).

I also need to consider that the game is in a scifi setting, so having some sort of health indicator is not completely unrealistic - especially since the 'healing' I talk about has the in-game explanation of using nanites. I think I could simplify the damage though, instead of giving a number, or a healthbar, simply give a short description of the upper/lower body health - something like "Healthy", "Bruised", "Damaged", "Severely Damaged" and "Disabled".

On top of this adding an animation effect for several stages would work - like limiping/reduced speed and forcing player into crawl mode. Not sure what kind of effect to apply for the upper body being damaged, but this is currently thinking too far ahead (animation is on my 'long term goal' list..er well it was)

Thanks for the input guys!

I'm a bit surprised that nobody has mentioned Fallout yet; each of those games featured damage to specific body parts (head, torso, each arm and legs) and the more recent ones (Fallout 3 and FO:New Vegas) would show the player the state of each of those parts on his/her character. It had very interest ramifications on gameplay. You could explicitly target an opponents leg, for instance, and on a solid hit you'd see that opponent move more slowly and with an obvious limp. Likewise, if your own leg was damaged (e.g. you step on a mine) your own movement would be slowed. Head damage was very interesting indeed, as your vision would blur and quiver, making it very hard to get by. I feel like these games make a good case study for your goals here.

I'm a bit surprised that nobody has mentioned Fallout yet...

Seconded. They handled the different injuries quite well I felt, though it seemed a little too easy to fix crippled limbs out in the field, making them a minor nuisance rather than a genuine threat.

To be fair, a lone man in a wasteland with a broken leg is as good as dead; it might make for an entertaining novel as the protagonist barely drags himself to salvation, but I suspect that'd make for some belabored gameplay. :)