Need help learning MAX's SKIN modifier...

[Slyrr]

I've signed on to help with modelling and animating for the HexenTC using the DOOM3 engine. I'm doing some of the beasts they'll be needing.

I use 3d MAX 4.2, which I know is older, but I can't afford $3000 to buy it again. I always animated with MAX's character studio plug ins, BIPED and PHYSIQUE. But I'm told that Doom3 'just can't' accept any model animated with physique. I have to use MAX's SKIN modifier instead. I don't know why, since both modifers do essentially the same thing. I'm just familiar with Physique and not familiar with SKIN.

But since I must now get familiar with SKIN, I've gone thru several tutorials on the web. However, they all seem to end before one CRITICAL point is explained....

How do you assign vertices to a control envelope on an INDIVIDUAL level?

In physique, the subobject mode in MAX let you select areas of a mesh by VERTEX, LINK, and ENVELOPE. For example, if you have a medium poly detail HEAD, with a bone for the head, and another for the jaw, and you assign PHYSIQUE, you would probably find some vertices that should be stationary on the HEAD (like in the area of the cheekbone or upper mouth) moving when you rotate the lower JAW bone.

In Physique, you could select the errant vertices individually, and then "ASSIGN TO LINK", select the head link and lock them. Then the lower jaw would no longer affect those vertices.

But with MAX's SKIN modifier, I see no such way to control individual vertices. All the settings and such seem geared to control the shape and influence of the ENVELOPES. I can move the envelopes, adjust their falloff rate, but no matter how carefully you refine the envelopes, there are still overlapping areas with lots of vertices and you get ugly flyaways with bones near the jaw as described before.

The "PAINT WIGHTS" doesn't seem to allow for much control. There are the "exclude" and "include" vertex buttons, but there are no tutorials on what they do, not even in the MAX HELP files.

Does anyone know a way to accomplish this? Or where to find a tutorial that shows you how? Unless I can select individual vertices on a mesh with the SKIN modifier, and assign those vertices to specific envelopes, I'll never get these meshes to animate properly.

Any help is appreciated.
Thanks in advance,
Slyrr

[FatAssasin]

There's a couple things you have to do before being able to select verts. First, check on "Vertices" in the "Select" section. Then, in the "Display" section, check on "Show All Vertices". Now you can select individual verts and assign them to bones using the weight table. Once you get used to it, it's much faster than having to lock and unlock verts all the time in Physique when you want to manually adjust the weighting.

I've written some more tips in another thread, but I don't remember which one. You should be able to find it with a search.

[Slyrr]

There is no "Select" section in my version of SKIN. (Bear in mind, this is Max 4.2 - not 5, 6 or 7) If you mean the SUB OBJECT flyout in the modifier tab, then all it has is ENVELOPES. Nothing else.

The only place where you can put a check next to the word "vertices" is in the FILTERS section of the tab, a box next to "envelopes" and "Cross sections".

And I see no evidence of the existence of any "weight table". The only things close to it is a section in the tab called "weight properties" where there is a "paint weights" button. But it still doesn't let you select a group of vertices and assign them directly to a specific envelope.

I think whatever version of skin you're looking at has very different buttons and labels than my version. Mine is the version that comes with Max 4.2. If your skin is for max 5,6, 0r 7, then direct comparisons will most likely confuse both of us. Is there a tutorial for max 4.2?

I've done a bizillion searches per your suggestion, and turned up nothing related. Any keywords I could try...?

[FatAssasin]

Hmm, I don't know what to say. I have Max versions 5, 6, and 7 installed, but haven't used version 4 in a while. I can't really remember what features it did or didn't have back then. I guess maybe there's a reason that Physique was more widely used at one time. It sounds like the Skin modifier wasn't as fully developed as it is now.

Try this, make sure "Vertices" is checked in the "Filters" section, select an envelope, and then select a vert. You should be able to change the "Abs. Effect" number in the "Weight Properties" section to increase or decrease the weighting of the selected vert to the selected envelope. Each envelope is associated with a bone, so weighting a vert to an envelope means that you're really weighting it that bone. The "Abs. Effect" spinner should go from 0 to 1, 0 means no weighting for that bone, and 1 means the verts is only weighted to that bone.

Hope that helps.

My other tips were for using the weight table which doesn't appear to be an option for that version, so they wouldn't help anyway.

[Eric Chadwick]

Once you follow FatAssasin's advice and understand Skin a bit more, you might benefit from using the tools on this page. Look towards the bottom for Skintools 1.32 (more help on this one (http://www.chuggnut.com/scripts/skintools/skintools.html)), SkinToolsEnv 1.41, SkinWeightingTools 0.5. I used to use these a lot in 4.2.
http://www.scriptspot.com/Main_Scripts.a...skin&Page=2 (http://www.scriptspot.com/Main_Scripts.asp?BrowseType=Search&Sort=Name&ST=1& SearchField=skin&Page=2)

Also this one might help you... an expansion of the weight table, which you should be able to see just fine, strange you cannot find it.
http://www.comet-cartoons.com/toons/maxscript.cfm#W

[FatAssasin]

Yeah, there are a lot of good scripts for Skin, especially the older versions. Like Discreet does with many useful third party tools, many of the older scripts are now incorporated into the shipping version of Max.

It think it's possible that Michael Comet wrote that weight table script because there wasn't one that shipped with version 4. But then Discreet added it into the next version of Max. That kind of sounds right if I remember correctly.

[Slyrr]

I'll look into it - thanks for your replies. But that weight table looks frankly baffling - so many windows, and no real clue what they're for. I'm not looking forward to using something that complicated...

[Eric Chadwick]

Ah, yeah it might not have been there.

Slyrr, you don't need the weight table yet, at least not until you have a better understanding of the weighting process. You can do all your work a vert at a time, with the Abs. Effect spinner... just takes more time.

Let us know if you have more questions. We've been there, we know how frustrating it can be.