Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[i2amroy]

When you put it that way, the solution sounds simple - just set a movecost threshold. Something that cost 200, for example, shouldn't hurt a vehicle. Something that costs 400 should, and a wall is just that - a wall.

I'd much rather alter the set "mass" of various obstacles so they can utilize the already present equations successfully. I don't want to move from a more realistic simulation to one that is more arbitrary if at all possible.

[Mephansteras]

When you put it that way, the solution sounds simple - just set a movecost threshold. Something that cost 200, for example, shouldn't hurt a vehicle. Something that costs 400 should, and a wall is just that - a wall.

I'd much rather alter the set "mass" of various obstacles so they can utilize the already present equations successfully. I don't want to move from a more realistic simulation to one that is more arbitrary if at all possible.

I think obstacles need multiple variables, much the way inventory has weight and volume to reflect different types of encumbrance. Obstacles need some way of knowing how difficult they are to move through and over.

Let's compare three different obstacles: A shrub, a small boulder, and a shopping cart.

The shrub is fixed to the ground, reasonably large (varies on the shrub, but somewhere between a house garbage can and a street-collection garbage can), and has very little density.

The boulder is fixed to the ground, somewhat small, but very dense.

The shopping cart is not fixed to the ground, medium size, and moderately dense.

A Fixed object is going to do more damage to something impacting it than a movable object (although enough force can move just about anything).
Size is a bit relative, but since we're dealing with a multi-tile system it's easy enough to put upper bounds on the size of something contained in a single tile.
Density reflects both the materials the object is made of as well as the structure. Both a shrub and a tree stump are made of wood, but the stump is much denser than the shrub.

So when you hit an object with a vehicle, you take all three into account.

The shrub is fixed and somewhat large, but has low density. It will probably impact a larger area of the vehicle but is going to do little damage and will probably end up uprooted unless the vehicle is going pretty slow.
The boulder isn't too big, so it can't hit much of the vehicle except what directly passes over it, but is dense and fixed so it will do a lot of damage to whatever hits it.
The shopping cart isn't fixed, so it'll move easily, and while metal and decently large it's too low density to do more than moderate damage to a vehicle that hits it even at fairly high speeds.

I don't have numbers in mind for any of this yet, but I think it'd be easy enough to come up with some sort of algorithm.

[Girlinhat]

Size and density aren't even really needed.  You just need one factor: Weight.

Size isn't important because we're on a resolution of 'per tile' here.  If a lamp post or a brick wall impact against a vehicle's armor tile, it's still dealing damage to that specific tile.  Size is actually irrelevant.

Density isn't important because size isn't important.  Density is a factor of weight and size, and without size density means nothing.

Weight, durability, and ability to move are all you really care about.  As soon as a vehicle impacts an item, it's weight * speed = damage, dealing to the vehicle and the obstacle.  If the obstacle is obliterated, the the vehicle continues moving.  If the obstacle is intact, see if it can be pushed aside.  If it can, then apply a thrust to send it flying away.  If it's stationary, then apply damage again at a reduced rate, since it can't cope with the impact, maybe 1/2 or 1/3 of the original damage to the item and the vehicle.  If the item is obliterated, the vehicle continues with the lowered speed and the damage.  If the obstacle is still intact, then the vehicle stops.

So a few examples?
The vehicle is roughly shaped as a common car, with Hard Plating on the front, making it durable enough to survive every impact.

Hitting a 20 pound bush at 20mph - the 20 speed * 20 weight = 40 damage - 20 is dealt to the bush and 20 is dealt to the vehicle.  This is enough to destroy the bush, so the vehicle continues with a small dent.

Hitting a 30 pound shopping cart at 20mph - 20 speed * 30 weight = 60 damage - 30 to vehicle 30 to cart.  The cart is very weak, and the impact totally destroys it, so the vehicle continues with a slightly larger dent.

Hitting a 150 pound motorcycle at 20mph - 3,000 damage, 1,500 to vehicle 1,500 to bike.  The bike survives the impact, and because it's mobile it's sent flying away, so the vehicle continues with a rather large dent.

Hitting a 100 pound boulder at 20mph - 1,000 damage to vehicle and 1,000 to boulder.  The boulder survives the initial impact, but because it's rooted to the ground it does damage again, dealing an extra 500 damage to the vehicle and the boulder, which destroys the boulder and lets the vehicle continue traveling with as much damage as if it had hit the bike.

Hitting a 500 pound brick wall at 20mph - 5,000 damage to both.  The wall survives the initial impact, so an additional 2,500 damage is dealt, but the wall STILL survives, leaving the car stopped forcefully and probably crippled.

These are all, of course, fake numbers and estimations of ideas, but terrain tiles already have their hardness coded in, which is why it's easier to break a window than to break a countertop.  Tiles cannot be 'damaged' they're either destroyed or not, so the 'damage' could be 'durability threshold' and if the total impact isn't enough to break it, then it's intact and undamaged.

Vehicles would also need to be given damage reduction values based on the type of tile - a tire takes full damage, a steel frame takes -5 damage, a board takes -10, adding steel armor stacks an additional -20, hard plating stacks an additional -50...  So if 100 damage is dealt to a board covered in hard plating, then it's 100 (damage) - 10 (board) - 50 (armor) for a total of 40 damage actually dealt.  This was a reasonably fortified vehicle would be able to mow through small trees and zombies, while a civilian car would have trouble handling shrubs.

Right now, all armor takes full damage from every source, and zombies end up ripping through 3 inches of steel plate with their bare hands.  Adding damage reduction would fix SO MANY vehicle issues.

[Mephansteras]

Ok, I can see that.

You still mobility of an object, though. Even though they are both made of metal and may have similar weights, there is a huge difference between a shopping card and a signpost in terms of the damage they'll do to your car. The shopping cart very quickly gets out of the way and a lot of the momentum of the vehicle is simply transmitted to moving the cart, which isn't resisting much so little damage is done to the car. The signpost is strongly resisting the car, so a lot of the energy is converted into damage of both objects before the sign post really starts to move.

[Sharp]

relative velocity is a factor as well. If your going at 1mph then you can just push along a shopping cart not really damaging vehicle or cart, if your going at 1000mph then the shopping cart will probably slice through the vehicle or disintegrate the cart (and vehicle?)

Of course if you steadily increase accelerationg from 1mph to 1000mph on pushing the shopping cart then still no damage will be done (ignoring friction which would probably cause some damage to both cart and vehicle) and then you can brake and the cart should fly off decelerating a lot slower then the vehicle and will cause nasty damage on whatever it hits.

[Girlinhat]

I modeled the 'shopping carts can get pushed aside' by dealing 1.5x damage to obstacles that are fixed.

I also modeled the 'you can push a cart at 1mph' by trying to urge damage reduction - it would be a series of soft impacts, but the armor would be able to negate the damage if it's that low.

Accelerating a pushed vehicle is probably beyond the scope of the physics and what we'd reasonably do, don't think it's that important.

[Mephansteras]

I modeled the 'shopping carts can get pushed aside' by dealing 1.5x damage to obstacles that are fixed.

Ah, missed the stationary part the first time. Cool.

Accelerating a pushed vehicle is probably beyond the scope of the physics and what we'd reasonably do, don't think it's that important.

Says the girl who wants to make a pushable shopping cart fortress. I'm not sure reasonable is a valid term around here. 

More seriously, I can easily see using pushing mechanics like that to both get stuck vehicles out of your way as well as avoiding damage to your own vehicle by having those plow into a group of zombies. And more specifically against a Brute or Hulk that could actually damage your own vehicle.

[HailFire]

So, just tried getting back into this... and I'm kinda bummed out now. 

I had an awesome martial artist with a shock module and solar panels, with plenty of forest and a nearby river to survive off of- but I ran into a smoker while raiding the town for the few supplies I needed, and promptly died to smoke inhalation being bugged and never going away. I think I saw it mentioned earlier in the thread that 0.7(.1) fixed this, and the client says 0.6, but it's what I downloaded off of both the website and the wiki, and the download links for the new version in the announcement thread throw up 404s. Could anyone possibly direct me to the real new version?

EDIT because I'm an idiot: The title screen does in fact say it's 7.1. Guess I just have to stay the hell away from smokers, huh?

[Imp]

Smoke can be prepared for.  A filter mask helps loads, a gas mask supposedly makes it harmless (I've never seen one of those in play), and I believe the bionic air filtration can help too.

[Akhier the Dragon hearted]

   One of the vital things I have found is to get a filter mask and upgrade to a gas mask as soon as possible. Smoke from fire and smokers, spores from fungus problems, and various other things are partially or fully negated by them. The filter mask is actually something I have found to be extremely easy to get as it only require tailoring 1 to make and uses 2 plastic bags or a plastic bottle and 2 rags, 1 muffler, 2 bandannas, or 4 paper wrappers. The plastic bags are easy enough to find and you can just empty whatever food item is in them out to use them and rags are just a window away.

[Girlinhat]

Do items like Chemistry Set do anything?  There seems to be no more crafting recipes for Mutagen, Purifier, and several other things, as well as the Chemistry Set doing nothing.

[guessingo]

@girlinhat: is this in the latest experimental from what day? I have not seen the chemistry set yet. note that if your using the experimental it will be way ahead of the wiki.

[azmodean]

I agree that in practice all we need is a single number representing how difficult an obstacle is to either smash or move out of the way.  In practice, all we have are terrain, which must be smashed to move past, or vehicles, which by default are pushed out of the way. EDIT: Also creatures, which are also pushed (and usually killed), they have decent mass granularity already.
The score for terrain is a gestalt value representing how hard it is to smash, some combination of mass and "rootedness".
For vehicles it's completely determined by mass to calculate impulse from the collision, at which point there's a momentum transfer and it moves out of the way.

The current problem is that all we have right now are a handful of hardcoded values for different categories of obstacle, so e.g. underbrush, picket fences, chainlink fences and railings are all treated the same.  Bashable obstackes are more varied, but based on their resilience against smashing attacks from the player, which probably doesn't match up very well.

EDOT: I agree damage resistance or thresholds for various parts would help a lot.

Also, I let the resident drive-by troll get to me and upgraded the FOV algorithm from bounding-box bresenham raytracing to shadowcasting, which delivers approximately the same performance as bounding-box without the intermittent draw artifacts.  It's also O(n^2), and will be O(n^3) with z-levels, where bounding-box was O(n^3) and would have degraded to O(n^4), so it might be sufficient for our FOV needs with multi-z level support, where bresenham raytracing would have definitely been too slow.

[forsaken1111]

I like that the troll is actually helping development. Just like he helped boost attention during the kickstarter and ensured that it succeeded.

[i2amroy]

Do items like Chemistry Set do anything?  There seems to be no more crafting recipes for Mutagen, Purifier, and several other things, as well as the Chemistry Set doing nothing.

AFAIK the chemistry set is just a remnant from the Goon Days merge, it doesn't actually do anything right now.