Completely new skeletons from scratch?

[Ra-az]

Ok I'll clarify..................

I want to create not only skeletons of course, but a complete model from scratch. Geomatry, bones and rigging. From some of the forums I read I get the distinct feeling that the CAS exporter can't handle that. Is this correct??

The importer doesn't seem to import the bones, just some points witch reference the bones (as far as I can see correct me if I'm wrong). That wouldn't have to be a problem but there are also no IK chains or even a reference so it's rather difficult to determine what different rigs I have to create.........

Any advice?

[wlesmana]

You can create a model from scratch, but you have to rig it to an existing skeleton. I assume that the skeleton itself is hardcoded, with the number and names of the bones must be what we have already. BUT, there's a skeleton with an extra bone: fs_slinger_new, where there's an extra bone called Bone_weapon or something like that. If you use this skeleton as a base for your model (aka. the Bone is present when you export it) and the skeleton file you use in the game is NOT based on this, then the model would get messed up bad in-game because the skin modifier would get confused by the extra bone. The reverse also produce the same bad effect. So I'm assuming that the bone names in your model do get exported into the .CAS file even if there's nothing rigged to it since the presence or absence of a bone do cause problems.

So, as of now, we can't add or remove bones from the pre-existing skeletons. We also can't change the xyz coordinates of the bones (EXCEPT for Scene Root), meaning only the rotations are read. However, as I've said above, there exists a skeleton with the extra bone so it might be possible to create new skeletons with extra bones but that seems to be hidden in the skeleton file or the packed files. There are at least some hidden files in there. The .evt files, for instance, are hidden and cannot be extracted by Vercingetorix's tool.

[Ra-az]

Thanks , I'll check it out.

[Bwian]

I don't see any reason why this COULDN'T be done.... it's just that Vercingetorix's tool doesn't allow us to. He was working blid, and could not get the detail he needed about the way the files were put together.

He made a tool that allowed us to do enough to mod with, and we were grateful for that. Development pretty much stopped. If you are in a position to take it further, then that would be good!

Here's a brief rundown on what I know about hte subject!

There are several different sets of bones, and each have different numbers and arrangements of bones. They all come from the root bone, which the game uses to position the actual unit. Right now, we cannot change ANY of this. We have the horse, camel, elephant, dog and human. I doubt you could create a vbrand new 6th type, but it would be good to replace ONE of those types with a new one.

The animations then act on the basic skeleton.

The key to the actual skeleton is to be able to read and re-write the skeleton.dat and idx files. Additionally, There is a skeleton text file, which was originally the source of the compressed files, but cannot be used instead...the game will not read it, and won't run without it. This tells the game which animation routines are used by each skeleton. They have a basic 'name' like, say, 'run' which tells it which animation to use when the game hasto make the model 'run'. Keep those bits intact, the the code should function.

We need to be able to define which bones go where, which bones are linked where, and then to build a new IDX and DAT file containing the new data.

Naturally, a full set of animations would have to be written for any new skeleton.

Currently, the animation and imprt/export tool is pure Max Script. XIDX is the tool that breaks and rebuilds the files you will need to look at. This has GOT to be the best starting point to understand the way it works. V has released the source for this. The best starting place would be to find out how to re-write the positions of the bone pivots. We can't right now. The animations routines ONLY store rotational data, and have to use the pivot locations defined in the Skeleton DAT/IDX files. Crack that, and you will be half way there!

p.s. More than happy to act as a guinea pig ;)

[Ra-az]

Thanks for your feedback Bwian,

Lately every answer I get just results in me having several more questions.

I contacted V he quickly guided me to the xidx source also. I can't blame him he's done enough and doesn't deserve people nagging him for pointers, lol.

I still don't get where the visible reference to the skeleton comes from in 3dmax when you've imported a model. For me it feels like its coming from the CAS file.

Anyway I'll look at the sourcecode for xidx first to see how it handles the skeletons.pack.

[Bwian]

The visual ref in Max has got to coe from the CAS file, but I suspect that is down to the fact that the model has a skin modifier which has to relate all the info back to a bone/skeleton to function. Basic skeletal information would have to exist there as a 'hook' for the games animation.

What is key here, is that the game is not taking it's information fromthe CAS file for how a skeleton joins together, so any changes made to the skeleton in Max are ignored by the game engine. Try moving a few joints around, and it is clear that this is the case.

It may be a function of the Max script not doing all it could, but I think Vercingetorix would have done that very early on if the CAS file could have been the key to this. I suspect rather, that he discovered the limitation of the CAS file in that respect, and didn't try to add any more functionality.

From conversations I had with V way back, I can recall his opinion on the Skeleton DAT/IDX files, and I am 100% sure that is the key. I am no programmer, but looking at things from a modellers standpoint, I can see the links between the the animations and the skeletons lurking in the file when I looked in notepad!

skeleton.idx appears to be just the list of skeletons that XIDX extracts into a .txt format.

skeleton.dat is the compressed and 'tweaked' version of descr_skeleton which relates all the animations routines to the skeletons.

Now....I gave this a bit more thought last night....

The animations CAS file only store rotations....aside from the ROOT bone, which has to allow translations to move the model. ALL of the subsequent bone 'children' are rotated only. Consequently, something must define the original position and relationship between the bones in the model.

It is possible these are hardcoded ..... but this has never been stated.

It is possible they are in the CAS file format, and Vercingetorix never cracked it. He was looking for a tool to do a job, and he gave us that. Maybe he never wanted more. Can't blame him for that...what he DID do was fantastic.

It is also possible that the thing is hidden in the skeletons DAT or IDX file. V's tool splits out the file into fs_whtever files, which sem to be the individual segments of skeleton.dat split up. The only human readable bits in there are the same as the descr_skeleton files.

One thing we DO know, is that the game cannot read descr_skeleton, and MUST have it in dat/idx formats to work. Jerome Grasdyke hinted that the DAT/IDX files were made from this originally, and that development builds of the game read it directly.

Now....if that is EXACTLY true....look in descr_skeleton.... no mention of bone names....

I certainly wouldn't rule out the CAS file having more nfluence on the situation!

[Ra-az]

I think you're absolutely right , what V gave us is great! Every word of critisism I might utter is simply a reflection of my own inadequacy.

V didn't include a lot of comments in the source (or in the readme's) so no way to profit from his acquired knowledge on the scope of the problem. But I'm not gonna bother him again before I have some real idea of a way forward expanding on his work.

Btw V also mentioned a program he wrote called "cas2rum", he suggested I take a look at that also. You know that one (what is rum*)?

l started reading his code(xidx) and will be piecing the logic of it together. One thing is certain, it will take some time.

Additionally I'll keep on building my mod. I still haven't even exported a model succesfully, I do get my unit in the game but he's all stiff in the design position (arms horizontally). Getting this working is also important to understand how it all works together. And it's a way to get some short term result, I've got to keep morale up, you know!

If I do get it (the bones) to work it won't be before MTW2, lol. But I don't care, if it works I'll be playing RTW mods hapilly for the next 20 years.

Thx (plse keep thinking aloud)


*yeh I know it's a drink.