Acceleration to top walking speed over a space of about .4-.6 seconds is what I usually use. I think the player should have a jetpack that only recharges on the ground (needs things from the soil to make fuel). An upgrade the player can get is a larger fuel tank (or two) that would allow longer flight. I also think it's important to be able to thrust downwards (hitting the down key in the air).
On the ground, the player should be able to jump a small height (jump boots, again can be upgraded) for use when something would wake up at the noise, or for moving around near heat-sensitive minerals (don't ignite that seam of whatever!), and also be able to crouch (down when on the ground) and crawl.

I think the player will be cut into 3 parts, body, head and arms. That way, we can have bodily animation that doesn't need to be reworked when the arms are doing something else (holding a gun, remote, animating while running, etc). The head can indicate aim angle without a crosshair (crosshair should only appear with a HUD upgrade when you've got a gun out). Having an item in your hand should prevent you from latching onto ledges.
featurecreepfeaturecreep

I'm also very much liking this system that's developing, but I want the ability to have a high destructive resistance of pixels that aren't intended as destructible (so the player can still make dents etc in that sort of terrain, but it's by and large still impassable), and also the ability to separate out "chunks" of terrain that will explode into smaller chunks upon getting destroyed. I'd also love love love the ability to settle stuff to the terrain layer, as well as turn a chunk of terrain into a physical object (for cave-ins etc). I'm pondering how I want this set up though, and caught up in friday night coursework (no party on may as well get it out of the way though) but I'm sure we can make something awesome happen. If we have the terrain stored at a pixel level and the ability to manipulate those pixels I'm sure we can get something together.
One annoyance with box2d that doesn't really matter for rock physics: polygon shapes can only have 8 vertices <_<

Current WIP most complete area. I can dump the whole thing if you want but there's a lot of painting to do for the objects, and then I have to do artefact placement and rework the area around them.

Great work Geti.

Now heres an idea, you could maybe make some kind of momentum feature, Like in Mirrors Edge where you run and the longer you run the faster you run. Maybe even upgradable too?

Also im surprised by how fast this is developing. Really, Great work.

Well, most of the design development has been done by the team working on the original game (like 3 times, considering how different each game looks), and then again by Arne. I based my plants on the in-game sprites and then extrapolated to the trees. I like using the whole "extinction" model for designing where you have a common ancestor to a whole lot of final designs, it makes the environment feel more coherent. I should probably go back a step too so I can have some better subterranean plants, the above ground plants seem way too leafy to be underground.

I haven't designed any animals, though I think fish could be fun. I'm not really sure what else I'd want though, I'm not really keen on the imps (I don't want to have to write an AI for them at this stage, though they'd be very fun to design cultures for) and I'm using beetles elsewhere so I'd be too tempted to cross-pollinate the hell out of it.. I might chuck in a meaty rhino beetle and some other insects as general fauna I suppose.
In any case, it's not all my work, not even close (Massive props to sneakymax for getting some coding done!) but I'm glad you're liking where this is going.

The problem with putting in a serious momentum system like in N or mirrors edge or whatever is it implies that the protagonist is really fit and strong. This guy spends a lot of his time in a spaceship, very likely in a chair, and then sometimes does stuff on the ground. As he's likely got some sort of dubious past he'd have to have some fitness, but I think in a game like this it's important to not let the player become a parkour god. I also think fall damage should be set nice and high to make the player think before they use their jetpack. You don't want to waste HP in a game with limited persistent items.

i was trying my shot at making a contour interpreter that could generate the "chunks" that make up digable areas for you so you don't have to place them, but im having some troubles.

I'm not trying to introduce a "serious" momentum system, just run about 2 metres (around 2' on-screen) and you run about 1/4 faster and thats it. It could help with long jumps or trying to get past a certain point, It doesnt even have to do with the character's physique or fitness, he could have some kind of booster jetpack or rocket boots! I say it could give the game a little more atmosphere to it. Maybe give it a try and if it doesnt come up as expected then thats that.

Or upgradeable jetpack

coops, see viewtopic.php?p=363321#p363321

Also 2m on screen is ~36px, or ~18ppm. Similar scale to CC, but with more chibi humans -> different scale sprites. Been talking with SneakyMax about how we're planning on doing the terrain, hopefully we can work something out that:
-runs at a usable speed on my 1.8GHz laptop
-allows us to do per-pixel physics on at least some of the map (If the whole map is impractical we could limit it to the surface layers of soil, for example).
-allows us to turn some of the terrain (specifically rocks or anything inorganic that would act as a solid rather than a powder) into chunks that are handled separately but can also interact with the terrain.
I'm assuming this is the area of the engine which is going to give us the most trouble, but we'll see how it goes. I'll hopefully finish painting the test level today I've got the terrain pretty much finished, I just need to paint all the objects and clean up the background, and then work out where items are going to be and a basic "item- get chain" progression.
I'm currently thinking that if you go into the large cave before you have a good jetpack, you won't be able to get out, so the player should find a discarded jetpack near the mining drill.. That or you get a grapple, but doing proper rope physics in Box2D is.. ugly at best.

3000x1400px full size.
Can dump layers of objects and background and whatever else (still haven't had enough time to do artefacts so this IS NOT FINAL IS NOT FINAL DON'T BASE FINAL EXPECTATIONS ON THIS and maybe shade the terrain more.) Still need to work on the rocks more too.

Whats your intention with the blue around the caves?

Also I dont know how I missed that part of your post about the running..

Im getting insane about already wanting to play around with this..

If the trees and such were kept a kind of sketchy style, as they are now, and would blow around a little, that would be an interesting effect. Not sure if it or crisp graphics would work better.

Man that level is sexy.

The blue is from

and

where the dirt is blue, I just thought it provided good contrast.

Be even more interesting to have that based on the current wind situation. We could just have 2 animations per tree (one for blowing in the wind in one direction, one for blowing in the wind in the other direction) and maybe one where there's no real wind, and do some scale/rotate magic. Good idea, but we'll need some way of not having wind in the caves, some sort of shelter calculation algo.

Lizard, glad you approve.

Github at http://github.com/Geti/EXILE
Sneakymax, I'd like you to push to my repo if that's okay, I've just merged in all your changes. When we have a release we want to make (a beta or whatever) we can compile everything, but for now I'll work on getting GPU padding happening (woo, white screen on old hardware, yay!) and my coursework

This development speed is insane...

This is a clue to a close beta test it seems?