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Rigging help
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Rigging help // New Users
Post by Igor K Handel // Jul 31, 2008, 2:41am
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Igor K Handel
Total Posts: 411
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Hi
I'm still trying to get my head around rigging etc and have a couple of questions. It just seems to work differently to other packages I am used to, so am having to go back to square 1 and relearn.
1. I've noticed in most of the rigs I have seen here that ik handles are created on the end of the hand rather than at the wrist, which is the way its done in other apps I have used.. Is there any reason it's done this way?
2. Once I have set up an IK handle for say an arm (eg. wrist to shoulder), is there an easy way to set up wrist only rotation using IK on a seperate visual control.. IE another IK handle perhaps or whatever so I can pose without even needing to use dynapose.
3. I get the impression that dynapose is kind of geared towards FK is this correct?
4. When binding skin to skel sometimes areas like eyes are difficult to select in the 3D screen. I have tried selecting the skeleton in 3D view then click attach skin to skeleton tool and then picking the eyes in LE or new scene editor list, but in both cases the focus switches to either LE or screen list, and the skin to skel selection tool is turned off. This happens even if I hold ctrl key. I also tried drag selecting the mesh object and the skeleton in LE window but again the attach skin tool de-activates lol. The Scene lister window doesn't appear to allow multiple selections using shift or ctrl so all in all I am somewhat baffled as to how to bind small inacessable groups of geometry.As ever its probably staring me in the face, but can I find how to do this.... nope
5. Is it correct to say that in order to bind an encapsulated group of small components I should only have to select the outer Encapsulation wrapper, not open it and select individual component parts of that grouping?
6. Does TS have the equivalent of nulls as found in some other apps?
7. Is there a simple way to assign my own seperate geometry as a control handles for joints and Ik. I realise that some sort of constraint or extra bone might be doable, but is there are more elegant way
EDIT.
8. I notice that IK is set to full FK in the options of many rigs.. what are the pros n cons of this approach, is it purely to have the option already built in? Why is there even an FK option in an IK system. Am I missing something here?
Apologies for the barrage of questions.. Just trying to get over this initial learning hump and and get to the fun/productive stage sooner.
IK |
Post by TomG // Jul 31, 2008, 4:30am
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TomG
Total Posts: 3397
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1. You can set one up any place you like :) I think setting it on the hand lets you bend the wrist, setting it on the wrist would just let you bend the arm but not the hand. Do either, or both, up to you :)
2 and 7. Yes you can have another control just for rotate. You can define what the IK handle manipulates. You can also define its geometry from a preset range of choices, so you can have a flat rounded shape for one that moves the limb, and a round circle for one that's a rotate handle, etc.
3. Not sure what you mean here, Dynapose uses IK - with IK if I move at the wrist, the whole arm moves to follow. With FK, the arm stays still and the hand is moves. With Dynapose the arm moves to follow. FK goes forward through the joints, while IK goes backward through the joints.
4. Once one skin is attached, I don't think you can attach another. You probably don't want eyes as skin anyway? You would use Attach Object To Bone for those? You could encaps the body and eyes then join it to the skeleton in one go. To handle weight painting, you can use the Point Edit hide tools - eg PE, select one face on eye, select connect to select whole eye, invert selection then hide - this would let you hide everything except the eye to go and work only with it for weight painting, etc. I think there is a section in the PE hide tools that looks into this (I remember writing it, not sure where is all :) It looks at using hide for working with eyes, the inside of a mouth, etc).
You could also select a bone and then use Attach Skin To Bone rather than Attach Skin To Skeleton (you need to manually assign weights when doing it this way)
5. I believe so, yes, just attach the encapsulated group. Unless you want to Attach Skin To Bone and manually attach elements yourself one by one.
6. Not sure what you mean by nulls - there is a way to do something similar, eg to attach a necklace skeleton to a body skeleton via an invisible bone. If you set a bone to Virtual prior to the Attach Skeleton, then it is ignored in the assigning of vertices, making it in effect a null bone, one that connects parts of the skeletons together, but does not itself influence any vertices.
7. See earlier, you can choose from predefined shapes easily. Most likely if you get into the LE and start editing you can make your own shape too, almost any widget or control can be modified.
8. I quote the manual (its well worth a read ;)
"
In full IK (Inverse Kinematics) mode, the limb fully follows the handle. That means if you add 2 key frames, then the IK handle will move straight between the two points and the limb will follow the handle.
In full FK (Forward Kinematics), the handle is moved as if only FK keyframes were made, so Handle follows the bone it is attached to, and will move on an arc. Values in between the two extremes will blend between those two values.
"
So with IK, the handle moves in a straight line from one keyframe point to another, and the skeleton follows that. In FK, the Handle will move in a curve from one keyframe to another, defined by the joints of the limb it is attached to. This would make a difference if moving a hand through space by a handle attached to the hand - with the first, the arm will bend inward as the hand moves in a straight line from A to B. In the second, the hand will curve from A to B, and the arm will not need to bend to follow the movement of the hand so much.
HTH!
Tom |
Post by Igor K Handel // Jul 31, 2008, 5:32am
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Igor K Handel
Total Posts: 411
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Thanks for the help Tom
I think what is confusing me is that I can use an IK handle to move with FK.
Previous experience tells me FK works by rotating single joints that are in isolation from the other joint rotations of the chain, which traditionally would also have to be individually rotated, normally starting from the top of the chain and working towards the end of it.
So for me using an IK handle for FK is like a contradition in terms. It's taking a bit to get my head round. That a TS IK handle in FK mode rotates more than 1 joint to me is.. well IK, then theres the the invert IK Groups option lol ....Time to book into a home for the bewildered methinks :p
Great idea using the point edit mode as a way of hiding for weight painting, I'll give that a go!
2.... From your description I read into it that therefore I can have more than 1 IK handle on 1 joint. IE at the wrist.. 1 ik with only rotate of wrist permitted and one to control the arm flex. Ok thats useful
I've re-read the manual a load of times... :D ..but theres only so much remembering an old codger like me can get to stick in the old brain cells at a time. So apologies for having to re-iterate bits of the manual.
I guess part of it is first remembering the approriate info and even then recognising its relevence when a situation arises that requires that particular snippet. Guess that'll come in time.
Many thanks for your help, will get there in the end.
IK |
Post by TomG // Jul 31, 2008, 6:04am
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TomG
Total Posts: 3397
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I always forget large parts of the manual and need to go back and read it (even the parts I wrote :O ). I think the wording of FK here is a little different, with the slider for IK to FK for the handle. Traditionally I am used to FK meaning just bending one joint at a time too, but this is a different kind of meaning right enough.
Keep asking those questions! I refer folks to the manual not to avoid answering the questions, but often because it does a better job in the write up wiht images to go with it, than I can put together quick here in the forums :) With the manual and some extra / alternative descriptions here, hopefully it will all begin to come together!
HTH!
Tom |
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