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vncnt
02-14-2010, 06:00 AM
I'm trying to use joints for facial muscles.

The rigging of the joints seem fine and easy to use.
I like the idea of primary and secondary controllers.

However, the deformation is not exactly what you would expect.
Can this be solved without too many changes in this joint structure?

SplineGod
02-14-2010, 09:22 AM
Instead of using limited range bones try using weight maps.
I did this example awhile back using standard bones/muscle bone and IKBoost.
http://www.vfxcast.com/media/1319/IKboost-Face-Rig/

jin choung
02-14-2010, 03:23 PM
also, it's not a good idea to have the hierarchy setup the way you have it.

have the bones radiating out from a central eyebrow parent so that the movement of one of the eyebrow points doesn't result in unintentional movement of other points.

so you have 4 joints that are not connected to EACH OTHER.

they are connected to a central "left eyebrow" joint placed inside the head somewhere probably near the eyebrow region.

jin

SplineGod
02-14-2010, 07:22 PM
I agree with that as well. I would spend some time experimenting with different joint setups. Also the flow on the areas of the mesh that you want to deform will also impact how the mesh deforms. That should also be taken into account when creating weight maps as well.
Another thing to think about is how to easily mix the facial poses like you would with morph mixer. :)

RebelHill
02-15-2010, 04:54 AM
Yeah, as said, use weights to control influence. As for the structure, i prefer a series of individual joints rather than chains as you have them, but either can work...

Download my 3 hours of rigging tuts, one of those deals with the setup of a face using joints.

vncnt
02-19-2010, 05:25 AM
For this test I'd like to focus on deformation. I understand that controllers can be arranged in better ways.

I did a test with a simple weight map but even then the deformation is too course and seems extremely difficult to control. The Limit Range has some influence but it feels like there are too many items controlling the skin.

The deformations with limited range in this tutorial were much better.
ftp://ftp.newtek.com/multimedia/movies/LW_9/Layout_FaceRig.mov

Is it because William is using a simple star pattern?
At the end of the video he does another setup - only using the first part of the joints.

Is my problem the fact that I'm using a chain of joints?
Or is it the direction of the joints (not sticking out of the surface like William did)?

vncnt
02-21-2010, 04:39 AM
Aha - solved the problem!

The object that needed deformation was using joints parented to another object and I changed the scale (can't remember if that was before or after resting the joints).

Anyway, as soon as I created new joints in my eyebrow object, even without weight maps or limited regions, now everything deformes as expected.

Jin: every secondary controller can be moved individually without moving any other joints.

In this setup I parented the sec/pri controllers to the eyebrow object so they move all together when the eyebrow object is moved or rotated.

I intended to create a rig like this one: http://www.vimeo.com/3077609

RebelHill
02-21-2010, 01:29 PM
I intended to create a rig like this one: http://www.vimeo.com/3077609

Doable. Some areas may be a lil tricky, Im imagining the eyelids straight off. Itll also take a bit of work to get the weights and influence right... otherwise all good.

vncnt
02-23-2010, 09:40 AM
Doable. Some areas may be a lil tricky, Im imagining the eyelids straight off. Itll also take a bit of work to get the weights and influence right... otherwise all good.

The same guy has made an Eye Lid tutorial too: http://www.vimeo.com/5299404

RebelHill
02-23-2010, 06:30 PM
The same guy has made an Eye Lid tutorial too: http://www.vimeo.com/5299404

Well, it is for maya...

Otherwise the main idea of using joints that part follow the rotation of the eyeball to create a soft eyes effect is the same way I do it in LW... the main difference being that theres no writing of expressions for LW way.

As for what he shows of using the eyelid joints to do the blinks n all... as he points out in the vid, a lot comes down to the skinning, which aint LWs strong point.

vncnt
02-24-2010, 09:14 AM
Well, it is for maya...

I think it's quite instructive and inspiring to have a look at solutions with competing products.

Some of the solutions translate really nice to LW9.6 and sometimes they clearly mark the weak areas in LW. Since I have little experience in other 3D-packages this is why I'm very happy with Rob Powers as a new crew member.

SplineGod
02-24-2010, 10:17 AM
You also have to consider the final result first and then figure out how to do that with a method that makes sense in LW. I dont see why a similar method couldnt be done in LW. :)

vncnt
02-25-2010, 11:00 AM
In this case I guess I was looking for a flexible approach that works nicely on my models without reinventing the wheel.

When starting with CA it's so easy to make mistakes in the rig that will cause problems during animation. Of course that has nothing to do with LW.

SplineGod
02-25-2010, 12:13 PM
Heres a simple test. Its using two bones with limited range on each. One holds the eyelid region and the other is pulling against it. I adjusted the bone strengths to vary the pull slightly against teach other. The blink is done using a morph. This is about as simple as it gets....2 bones and no weight maps. From here you could make it more complex if necessary. The eyeball is parented to the 2nd bone that is giving the fleshy movement to the eyelids.
http://www.vfxcast.com/media/11170/Eye_Rig_Test/