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[Aqizzar]

I think many of them won't even be measured in any readily available way (shear yield of microcline, etc.).

Hmm well I do have access to several academic sources... Hmm maybe I am confusing what Toady put here.

I think he means that, for a lot of extraneous information like microcline shear yield, the game itself won't use the numbers often enough for accuracy to be important.

[Neonivek]

Alright so he isn't saying I can fill in that information for him.

[Akroma]

I admit, I would laugh a lot if the description paragraph of the right hand, third finger would state that this finger is ultramighty, whereas the 4th finger would only be mighty

[Toady One]

What I was saying is that I would be surprised if readily available sources on certain minerals use the same 6-way split for mechanical information I used, as there's nothing standard about it -- I couldn't find a standard split and there are a several different tests for impact alone, many of which might not have been run for the more esoteric minerals.  Finding torsion information on microcline vs. shear information vs. impact vs. compression vs. bending vs. tensile information just might not be doable.  I'd been using some cludge where I'd just use the numbers I could find and use them for any missing categories as well.

[Mel_Vixen]

Heh maybe someone with a degree in material-science or architecture has the numbers for you. You were a Prof. dont you know some colleagues who could have the fitting knowledge?

Hmm i could ask around if one of my friends knows someone who could help out here.

[Jurph]

Yeah, I've generally accepted sourced updates to the real world numbers if there's not some kind of game obstacle.  I'm not adding new minerals or vermin or anything, even real world ones, that other people write up, but a sourced number is fine.  Especially with the next release, there are far too many numbers to do, and I think many of them won't even be measured in any readily available way (shear yield of microcline, etc.).

I've got a stack of materials science and environmental engineering texts leftover from my mechanical engineering days in college, including some seriously esoteric tables of material strengths.  If there are raws you'd like to point the community towards, I can probably start making contributions. 

[Footkerchief]

I've got a stack of materials science and environmental engineering texts leftover from my mechanical engineering days in college, including some seriously esoteric tables of material strengths.  If there are raws you'd like to point the community towards, I can probably start making contributions. 

Preview of raws for the next version.  "Material Templates" is the one where numbers are most needed -- they're the default material properties, which most materials inherit unaltered.  The last six ("Layer Rocks" through "Plants"), which specify properties for materials that deviate from the defaults, could also use some specific numbers.  Obviously the fictional/fantastical plants are anybody's (well, Toady's) guess, but the real trees mostly just have individual densities and lack individual yield/fracture/elasticity stuff.

I don't know whether Toady would prefer that you send him edited raw files or just lists of properties in the order they occur in the files.

[Great Cthulhu]

Wow. That's a crapload of new stuff. Cool!

I went ahead and created a public spreadsheet in google docs containing all the data I've collected so far. It's linked from this thread.

[Dame de la Licorne]

Also, check out this topic in the modding forum.  I believe the idea is for all collaboration to take place there so as not to derail this thread any further.

Edit: Beaten to the post. 

[Jakkarra]

not to sound Ignorant, but, how exactly will the proposed shear strengths and whatnot actually effect the game?

i am assuming it will mean that, Hypothetically;

Hammer A (wooden) strikes Urist Mcsoaper in the face, causing bleeding, bruising and small fractures,

whereas,

Hammer B (iron) strikes Urist McMilker on the noggin and crushes the cranium.

and other scenarios of a similar vein. basically meaning that any particular object's interaction with another entity is correct for the item type, weight, material and so on.

Am i correct in my assumption?

love, jakkarra

[Footkerchief]

not to sound Ignorant, but, how exactly will the proposed shear strengths and whatnot actually effect the game?

i am assuming it will mean that, Hypothetically;

Hammer A (wooden) strikes Urist Mcsoaper in the face, causing bleeding, bruising and small fractures,

whereas,

Hammer B (iron) strikes Urist McMilker on the noggin and crushes the cranium.

and other scenarios of a similar vein. basically meaning that any particular object's interaction with another entity is correct for the item type, weight, material and so on.

Am i correct in my assumption?

love, jakkarra

In your example, it's the material properties of Urist's tissues that are likely to play a more interesting role, due to their much wider variety.  Toady posted a bunch about this stuff in the NFotF thread (it was all being discussed prior to the List), here's some of it:

How much does this (skin thickness) actually matter in terms of combat?  Will there be things that daggers can't cut through?

That's coming up very soon, so I can't say exactly how much.  The idea is that a thicker tissue would matter a lot, so a bulbous creature with a large layer of lardy rolls would have a great deal of protection.  It'll take some balancing, and I'm not to the point where I've tested it out.  In terms of daggers being able to cut in general, it currently uses the shear properties for this, and if the dagger is a harder material it will form some sort of cut (assuming the strike is forceful enough to get beyond the shear fracture point for, say, skin), but on a titan, that should be neglible unless you make a hobby out of it.

Does bludgeoning damage transfer?  (AKA is unlikely to do damage to skin or fat but will bruise muscle and break bone)

Yeah, though it's sort of cludged since there's a lot going on and I wasn't quite wrapping my head around everything.  Right now it'll check the impact elasticity (which I guess is actually impact yield strain or something) of the outer layer, and that'll let it bypass impact fracture after a certain point (while still allowing bruises and ruptures without the layer eg skin actually breaking) even if the force is high enough (as the layer is assumed to have made way for the moving object in a sense).  So if you make a michelin man style creature that's just a purely elastic material, a mace will be unable to harm it unless it has blood flow and can bruise and so on, while relatively inelastic materials like bone will fracture, even through skin.  Skin has a lesser shear fracture than bone on the other hand, so a knife will cut through skin more easily than bone.

This can all use a bit of work, but I'm hoping to get something that seems sensible during play out of it this time around.

So we'll also have armor acting like a pseudo tissue layer for purposes of transmitting bludgeoning damage and so forth?

If an iron sword strikes some steel plate armour and fails to penetrate it, and the damage is converted to bludgeoning (AKA the force of the blow is spread out over the plate), will bludgeoning damage be inflicted to the creature beneath the armour?

Additionally, if we're talking about a steel-skinned creature (Giant Magma Ants?) instead of a steel-armoured creature, is the force transfer handled differently?

Yeah, that's basically how it works.  The armor is all checked in order from outer to inner, then it gets at the tissue layers, altering the character of the attack as it goes.  There's a little left to do there, so it's not completely clear to me which way it'll go as far as how much force is transferred (or if it matters if it's skin or armor -- it doesn't currently, though yeah, there is a difference in real life).  It has to be enough that skin doesn't stop bones from being broken, but not so much that armor is useless against impacts, depending on the mats and nature of the armor/clothing.

Obviously, from what you've said, it will be difficult to cut through, say, steel with iron. But HOW difficult?

I've only whacked the poor dwarf with the hammer.  Haven't tested armor yet, and all of this is very number dependent.  Ideally, there would be a point to upgrading equipment without making the prior equipment worthless.  A softer material can break a harder one with impact force currently if it's swung hard enough, but it would suffer itself in the process (though not so much if it is against something that just isn't as massive as it is).  There's a sort of mid-range spot I'm missing right now with wedge effects (like a dull axe), but I'll get at that at some point -- I have a contact area variable in the attack definitions that should make the pressure increase, but there are many things to balance.  There's a sweet spot we'll find eventually as long as everything is placed correctly.  Skill is probably still going to be the most important thing, unless you've got really really tragic atts or something (you can't be strength 0 unless you wait for your atts to rust for a long, long time, but if you theoretically did get down there, you wouldn't be able to cause any damage at all).

How do the strength values for metals interact with their effectiveness as weapons and armor?

Currently shear yield/fracture is used to determine edge effectiveness and the effectiveness of a material against a cut.  Impact yield/fracture is used to determine resistance against impacts.  Solid density will increase weight and therefore the impact of attacks.

Also, the oddball properties do at least get used for wrestling:

Are you going to give us details about how all the numbers work in the raw files?

There are some details in the material template preview.

As a note, some of those "unused" ones have uses now -- all of the things like compressive/tensile/bending/torsion get used during wrestling, but that's about it I think.  They are around if we need them now though (not that it was easy to find any numbers, so most of the numbers are copies of ones I found for other materials or types of force...)

[SirHoneyBadger]

As far as stone goes, I'd assume--and this is just a guess--that it'll have a good degree of impact as geology becomes more realistic.
Earthquakes, caveins, etc. might have different effects on different types of materials, whether they're in the ground, or part of a building.

Mining out a section of microcline might be different than mining out a section of granite, and it might even lead to requirements (or more likely just different mining rates) for harder and better picks (steel instead of copper for granite, etc., with maybe quality of craftdwarfship coming into it? Can quality of items affect the properties of the material they're made out of? This occurs in real life--Steel is a good example that should be well understood, but even something like cold forged copper can have a wide range of hardness, elasticity, and other properties greater or less than "average". Wood can be heat-treated, etc.).

Maybe even some differences when it comes to engraving, or decorating with stone?

[Neonivek]

Well when I checked the material strength of rocks a while back (I was actually getting the material strength of Glass to prove that glass actually wasn't a weak substance and its nature has a bit more to do with the fact that it is thin... and I was right) they split up a few types of rock. (Concrete, Marble, Stone)

The actual conversation was interesting... It was mostly someone saying that a 1x1 meter ball of glass would shatter upon first impact with a solid object.

There is varying degrees of strength in stone.

[ArkDelgato]

The combat system is looking really slick for the next release.
I can't wait to see how many threads try to find the max bending point of elf.

[Pruvan]

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