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3ds max bones

Started by March 12, 2011 06:04 PM
7 comments, last by Payam 13 years, 9 months ago
Hey guys, I'm trying to animate a character I made with bones in 3ds max 2010. In Cinema 4d and Character FX, I assigned vertices to each of the bones so it animates properly, but in 3ds max, it wants me to use these weird envelope things that assign the vertices within it to the bone. For the sake of simplicity, I just want to assign vertices to the bones instead of using these envelope things, is there a way to do that? I would use Cinema 4d or Character FX, but neither of them have a free Ogre exporter or an animation format that 3ds max can import. Thanks for any help.
Sure thing, it's totally doable.

In order to "manually" select which vertices are assigned to which bones you need to enable Vertex selection:
Open your Skin Modifier rollout and toggle the button Edit Envelopes on, to activate envelope editing mode. As soon as you toggle that button you'll notice right below it that there is a "Select" group, with a checkbox for "Vertices". Check that checkbox so you can manually select vertices.

Now you can assign vertices to bones with the following workflow: select a bone from the bone list, select the vertices you wish to assign to this bone, scroll down the Skin Modifier rollout until you see the Weight Properties group where you can adjust the Absolute Effect (commonly known as Weight) value that that bone will have upon the selected vertices: a float between zero (no influence at all) to one (complete influence).

Sometimes when changing the Absolute Effect value you will notice some vertices will start to move; to avoid this, toggle the Normalize checkbox (it's in the same Weight Properties group).

Do know that when you change the Absolute Effect value for some vertices, other bones that also influence them will have their weights adjusted accordingly: all the weight values from different bones upon one vertex will always sum up to 1.0.
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I'm trying this, but it's not working.

1) In order to access the skin modifier rollout, you must select something. Do you select the bone you are interested in adding vertices to or the area of the mesh you want added to the bone?
2) In both cases, after enabling Edit Envelopes, I cannot check the box for selecting Vertices. It's grayed out. This is in Max 2010.
Ok I got it. Select the mesh first. Then following your guide works =)

edit: Ahhhh! Can't add hidden bones using the method you described T.T
Yes, the Skin modifier is applied to meshes - so in order to access the skin modifier rollout you need to select your character\mesh that has the skin modifier and proceed to the Modify Panel. Then toggle the Edit Envelopes button so the Vertices checkbox is 'enabled' for checking\unchecking.

When you click Add in the Skin modifier rollout it will open the Select Bones dialog. This dialog allows you to select which visible nodes you want to use as bones. Note you don't necessarily need to use bones\bipeds as bones. You can select any object in the scene - some artists prefer to use custom mesh structures as bones, structures that look like a very low poly version of the mesh they are rigging.
Different skin modifiers can reference the same bone.

Anyway, after adding bones to the skin modifier's list you can now hide them and they will still deform the skinned mesh they are applied to. This is useful when you want to use animation controls to make the process of animating easier, so the scene is less cluttered with objects.
It's much easier working with controls than directly with bones.  
Thanks. I have 1 last question though. You mentioned you can assign multiple bones to the same vertices and give them different weights that add up to 1. I can't seem to do this.

If I only add 1 skin modifier and add 2 bones, 1 always ends up with an Absolute Effect of 1 and the other 0, whichever I modified last, even when I give both a value of .5.

If I add 2 skin modifiers and 1 bone each, the same thing happens. Whoever was modified last get an Absolute Effect of 1, even when I set both to .5.
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Are you adding two skin modifiers to a single mesh? each mesh should only have one skin modifier; never add more than one. 

Also, consider each Skin modifier a separate system: the weight of bones belonging to a certain skin modifier will never influence the weights of bones in another skin modifier (even if both modifiers reference the same bone). The weight values are stored in the modifier, not the bone objects themselves.

I don't know what you are doing differently. Try this: Create a box, create a single bone close to it (the end bone will be created automatically, so in fact you will have created two). Apply a skin modifier to this box, add both bones. Click Edit Envelopes - check Vertices. Select a certain vertex of the mesh, and with a bone selected in the bones list, change its Absolute Effect to 1.0 (if it wasn't 1.0 already). Select the second bone in the bones list and set the Absolute Effect to 0.5.
Now head back to the first bone you selected and see the Absolute Effect for that vertex. It will be 0.5, I'm sure. 

EDIT: OH! perhaps that vertex is setup as 'Rigid', which means it will only be influenced by the bone which influences it most. This bone will weight it with 1.0, always, no matter how many times you manually set the values like it's happening with you. Select all vertices in the mesh and unmark the Rigid checkbox (it's just above the Normalize checkbox close to the Absolute Effect spinner). Rigid Handles is when you are skinning editable-patch meshes, so you can leave it off for now.  
Thanks for the help!
Kryzon's explanation was actually very good! Props to him!
http://www.gamedev.n...97748-mmo-shax/ <-- Great new Action-oriented game!

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