Ramblings: Internal and external HUD elements.

When comparing the total number of occurrences of HUD Elements in the games it turns out that elements conveying internal states outnumber the external states 2:1.

This is interesting to think about since the internal states like health, stance etc is something that, in real life, would be percived through one or several of the senses not available when playing games.

In an FPS you do not have access to any form of direct proprioception. (That's a fancy word for your body's sense of its own physicality — its "map" of itself. Proprioception is how you know where your various body parts are — and what they're doing — even when you're not looking at them. It's why you can pass a ball from one hand to another behind your back; it's how you can climb stairs without looking down at your feet)

Because of this - HUD elements need to be contrived in order to convey this type of internal information to the player.

Looking at the outside world however, is a different thing. Here reality and the simulated game world have much more in common. We can use the same perceptual abilities (spatial awareness, locating sound through stereo or surround effects etc.) to evaluate states in the external world.
Therefor, there is not the same need for HUD elements to convey information to the player - since this information can be elicited from the world itself in a natural way.

Instead, most external elements are either present in order to compensate for the loss of some of our senses (stereoscopic vision for example) or simply implemented for the sake of usability or practicality.