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[exile]

"Smooth_immobile" is made like in the hand tutorial, but with more segments to have space between the fingers. Tried to animate the hand and fingers using the skinning feature, probably there were too many bones, didn't work. "Seamy_joints" is ugly but functional, each finger and the thumb are cylinders attached to their own separate two bones. It opened and closed surprisingly well. Is there a way to smooth over the places where the different objects join?

I'd appreciate tips on modeling and animating hands from more experienced users. (Searching the forum was difficult, because "hand" or "hands" gives all sorts of search results.)

[exile]

Since forum members seem to be reading my post, I'll update: I tried using morph targets instead of bones to move the "smooth hand". Not too bad, although more control and ease of positioning the fingers would be nice. I noticed that the conversion to subdivisions had no effect on these edits - the number of points for the 3 extruded joints of each finger stayed the same. Also, selecting faces is a much faster way of working than selecting points, but it's easier to mess things up, too, especially if x and y are both selected. I don't know if more segments would be better or if too many points would make the operation even more tedious.

Hands are difficult in all kinds of animation, but a small library of hands that work well could be used with different characters.

Update: The morph targets have to be inserted in the timeline at 1.0 - trying to gradually close the hand results in horrible distortions.

[davdud101]

Hands are pretty difficult.
Remember that morph target points move in a straight path to their morph, so if you want a round motion (like you'd see in a real hand joint), you could either use two separate morphs in two positions, or just use bones. Bones would certainly look the best and give the most flexibility. Plus, you don't have to worry about making the two sides of the hand perfect in their morphs, just the bones (which I find way easier).

If the "horrible distortions" are something else, perhaps it's because you're using integers or values greater than 1.0? That causes the morph points to continue in their straight path and go over the "target" amount, though it can be used to good effect in cartoony characters when you want to bring a little bit more life into facial animations and stuff.

Good luck!

[ENSONIQ5]

If the Figure is using multiple separate objects there's no way to smooth them together, if you want smooth joints the hand and fingers will need to be a single object.  Using separate objects is ok if you're building a robot hand or a gauntlet or something like that, with solid parts that hinge or interlock.  The trick with organic models is to have enough vertex points in the right locations to allow the mesh to deform with the bones; moving the bones won't bend a line between points, it will only move points themselves, so if the points aren't in the right place the mesh won't deform as you expect.

In Figure mode, you want to build the skeleton structure such that bone joints coincide with the clusters of vertexes in the model.  Mapping which points move with which bones is the really tricky part.  Using 'bone influences' is generally more accurate than 'weight painting' but they can be problematic around the gaps between fingers as points are mapped to bones based on the distance from the bone to the point.  Weight painting allows you to manually map points to bones, regardless of their relative positions, but can be trickier to master and is more like an art than a science.  One method is to start with influences, setting the influence ranges as accurately as possible, then switch to weight painting to make adjustments.

In the example below I used weight painting to map points to bones (not very well, there are a few places where the points don't move evenly in the test animation).  As davdud101 mentioned, hands are kinda tricky due to the proximity of the fingers to each other.

[johnar]

 Hi there exile,
 Good advice from davdud and Ensoniq5
 Although it may all seem a bit confusing at first, you keep at it and things will come together.
 (when weight painting, remember its the vertices that 'take' the weight, not the faces)
 
 I would suggest using a reference image to model a hand, and make sure the fingers have a reasonable gap between them. The an8 hand tutorial uses 'box modelling', which is great.
 Check some other 'box modelling a hand' tutorials online as well.
 Heres one, and although it was written in blender, its just as do-able in anim8or.
 Box modelling a hand:
http://blog.teamthinklabs.com/index.php/2012/04/03/box-modeling-for-total-n00bs/
 
 The only thing i would change here is the amount of seams at the finger joints. As you reach a finger joint, give 2 extra 'short' extrusions before the next 'main' finger extrusion. This will give you 3 seams at each joint, rather than just 1.
 The only real way to animate hands successfully is by using bones. 3 bones for each finger an 3 for the thumb. (although the first thumb bone is lodged 'in' the side of the hand)
 Once you've got a hand model you're happy with, and a skeleton to fit it, then try skinning again. Take note of what Ensoniq5 said...

"One method is to start with influences, setting the influence ranges as accurately as possible, then switch to weight painting to make adjustments"

.
 As you make progress with the skinning in figure mode, switch over to sequence mode and test each finger, then back to tweak in figure mode, then back to test in sequence mode... and so on, till you get the fingers animating well.
 The BONUS payoff you get when you're happy with the results is:
 .

....a small library of hands that work well could be used with different characters.

You can do this by making sequences. Single frame 'pose' sequences and also multi frame actual sequences. (the rig must be the same rig, but a different character can be attached, as a new/seperate figure.)
 nb: With 2 or more 'pose' sequences, added in scene mode, anim8or will make larger proper sequences by filling in the gaps.ie: frame 10 -> flat hand pose sequence, frame 15 -> closed hand pose sequence. When you play the animation, anim8or fills in frames between 10 and 15, and the open hand will close.
 So rather than making a sequence of a hand closing, you can leave that movement up to anim8or.
 Naturally, the same applies to any single pose sequences.
 (actually, 'pose sequence' is not the best description. Its really just a pose, made in sequence mode.)

 
Questions welcome.

[exile]

Hey everybody,
Thanks for the great suggestions. I loved the elegant motion of the animated gif hand. The image including the bone structure is very helpful. BTW, thanks to Johnar also for his eye morphing tutorial that I was able to duplicate. It will take a while, but when I have something finished I'll post it here.

[Kyle]

I never did figure out how to rig/animate hands myself.

Apparently its even difficult for Nintendo. With games like Mario Galaxy or 3D world they swap in different poses for each frame, stop motion style.

[exile]

Can't seem to get it better than this - not usable. Don't know what's wrong.

[johnar]

 Had a quick look this morning before work.
  I've moved the 3 shorter knuckle extrusions further apart and changed the joint limits.
 2nite will try some more. (am now beginning to doubt my suggestion of the 3 extrusions rather than 1, seems to be something not quite right)
 Maybe compare with a hand with only the 1 seam per knuckle?
 Looking a little better now, will have another look 2nite.

EDIT: weight brush can be edited by going 'Build => weight brush'
 Try radius of 12 and strength of 5 or 1, for easier painting.

[johnar]

Giving finger/thumb bones some limits is pretty essential. I've changed the limits, check them out.
 Was in a bit of a rush this morning, been a while since skinning a hand, but it's come back to me now. (this method not really just for fingers. Try it everywhere.
This is 1 finger.

 Start from the tip of the finger, with a weight brush strength of 1.0. Paint the seams points as
shown in the pic along the top. (both ends of seam). It won't look exactly like this, but it will later. So that's 4 seams purple, (tip of finger), 3 seams green and 3 seams yellow, as shown by the colored numbers.
the finger should look like this pic below after you've painted the '1's'

 Next, set weight strength to 0.5.
 Start at the yellow bone, (painting yellow), and paint the middle seam between yellow and green,
but only paint over the vertices ONCE. This is important, because once-over will give a strength
of 0.5. If you paint it again, the strength will increase.
 Then do the same with green to purple. (middle to tip of finger) Paint the middle seams vertices green, and ONCE only.
 I included the purple 0.5 at the base of the finger. Although that purple part of the hand isn't animated the yellow part of the finger is, so the theory/method remains the same.

EDIT: To avoid confusion.
 Once you've done the '0.5's it'll look like the top pic. (although i haven't painted the '0.5' on the 'purple to yellow' base of the finger.

[davdud101]

EDIT: To avoid confusion.
 Once you've done the '0.5's it'll look like the top pic. (although i haven't painted the '0.5' on the 'purple to yellow' base of the finger.

Possibly the only thing I really dislike about Anim8or. Models should actually maybe start black or white BEFORE you paint them so you can see what's painted and what's not.

[exile]

Thanks so much, Johnar, Davdud, Kyle and Ensonique5. Do I understand rightly that the side that gets the strongest weight is the one that borders on other fingers? Does that mean the middle and ring fingers should be 1.0 on both sides? Not being able to see the strength probably means starting over again if it doesn't work as hoped for the first time.

The revised model works much better than mine did, although I don't know if it's an animation revolution yet. The enclosed gif shows every 4th frame, so actually it's smoother, using only 2 key frames. Couldn't get the thumb to do what I wanted, just now realized the middle thumb joint was constrained not to move at all. I'll play around with those settings to see if it can make a fist.

Kyle mentioned switching hands, which I know about from 2D animation - most Anime Studio users put a set of hands on switch layers so any hand shape is available on any frame. Is that possible with Anim8or? Of course one hand that can make every pose would be the most elegant solution.

[johnar]

 

Do I understand rightly that the side that gets the strongest weight is the one that borders on other fingers? Does that mean the middle and ring fingers should be 1.0 on both sides?

 No, the 2 outer seams of a knuckle get 1
 The middle seam of the knuckle/joint gets 0.5

Not being able to see the strength probably means starting over again if it doesn't work as hoped for the first time.

 To reset the strength of a 0.5 middle seam, just paint again with the adjoining color, using 1, and the touch again with the 0.5 of the required color. (just as you originally paint the middle seam of a joint with a '1', and then go over it with a 0.5 of the second color.
 (the pictures above are back to front.
The 2nd picture is what it looks like after painting the 1s.
The first picture is what it looks like after finishing with the 0.5s

davdud101 Yes. Actually i think that was talked about in the 'ongoing builds' discussion..... might see if i can find it......

[ENSONIQ5]

The idea with weights is that points mapped to a particular bone with a weight of 1.0 will not change their position relative to that bone.  So if the bone moves, those points will be effectively locked to it.  Points with a 0.5 weight to one bone and a 0.5 weight to an adjoining bone will be partially mapped to both, so if one bone moves and the other doesn't these points will kinda spread out or bunch up in an 'organic' way.

That's a bit of an awkward explanation.  To use an example, if you consider a point on your forearm midway between your elbow and wrist, that point is entirely locked to your radius bone (ignoring the mushyness of flesh and the fact that wrists can twist).  Regardless of how you bend your elbow or wrist, that point effectively maintains its location relative to your radius bone.  Consider another point midway between your elbow and shoulder, that is similarly locked to your humerus.  But if you look at your elbow, there are 'points' there that are kinda influenced by both bones, so the skin stretches on the outside and contracts on the inside when you bend your elbow.  The bone influence and weight painting functions simulate this by allowing you to define how (and how much) these 'intermediary' points should move when the skeleton moves.

So, when you're mapping your hand model, all the points that need to move 100% with, say, the tip of the pinky should be mapped with a weight of 1.0 to the pinky tip bone.  But those extra points that were added at each joint need to be mapped partially to that bone and partially to the next one down, so they find a half-way position when the pinky bone is moved.  No points on the fingers should map to more than one finger, otherwise when you move the pinky some of the points on the ring finger will move, which isn't what you want.  The 'soft gradient' that can be obtained with the weight painting tool should only be between points associated with two adjoining bones, so those points move in an 'organic' way when a bone is moved.

[johnar]

 Nice one ENSONIQ5 

 An interesting thing is the way a 'thumb' is actually set up in real life:

 Notice the thumbs in regard to positition and skin cover.

 This is froyds hand:

Theres only 2 bones in the actual thumb. The 3rd bone is in the side heel of the hand, and that one moves, unlike the rest of those hand bones, which are static.

 So this thumb setup, which seems the most common way of setting up a hand rig,
,
 is fundamentally incorrect... ...