Lips rigger and blendshapes

[niteshms04]

Hi,

In my production we have a character which need to go to unreal with good facial setup. So I’ve been trying to integrate the lips rigg with the blend shape. I’m facing this weird deformation issue.

This is just a normal mouth open with the lips rigger used(not skinned properly yet).

my bend shape without any skin deformation.

This is when I open the mouth with lips done and the blend shape switched on. As you can see it does not work as it’s supposed to.

Any information on how to solve this would be really helpful.

Thanks

[pascalf]

Hey

when you activate the blendshape, and the blendshape deformer is in front of your skinCluster in the deformation stack, you change the positions of the vertices that the skinCluster will deform from the lips rigs. As you change the position of your vertices, but not the position of your joints, you change the behavior of the skinCluster deformation, as you changed the relationship between the joint placement and the vertices of the lips.

One way to get the effect you want, or at least that’s what I’m guessing, is that you duplicate your head, and you input your blendshape and your skinDeformation as targets on a blendshape node on the third head, and activate both. Not sure If that will work with Unreal though.

Hope this makes sense!

Best,
Pascal

[niteshms04]

Hey @pascalf

That way doesn’t work for unreal. So i am limited to the joint and blendshapes to a single face.

[pascalf]

Then I’m not sure if you can solve it this way. You would need to create the side motion of the lips with the skinCluster as well, maybe add some correctives on top.

-p

[Krzym]

Hi! Connecting to this topic, I often have to do that the same way, as keeping those things layered works best in most cases and correctives on a single one. But maybe anyone has a better solution for that, as it does not seem like the best way of solving that.
How do you manage that on a single face like in @niteshms04 example?

Cheers,
Krzysztof

[Tsahi]

Have you tried reordering the inputs on the head model so the blendshape node is before the skin cluster?

[chrislesage]

I moved this to “Rigging General”, because this isn’t an mGear problem. It’s just the way Maya works.

I have a blendshape that is empty, but it turns on when the jaw is open 30 degrees. Then I can use that empty blendshape as a basis to sculpt some corrective blendshapes when the mouth is open.

It doesn’t solve the issue, but it is one way I fix some poses in some situations like these.

Sometimes you might also need to use a tool that can extract the deltas (the difference) of a skin+blendshape, so that you can write your blendshape back to that pose, minus the skin effect. I never used BraveRabbit Shapes, but maybe it has some tools for this?

[pascalf]

Yes, SHAPES from BraveRabbit does that. Also you can check out cvShapeInverter by Chad Vernon.

[niteshms04]

I’ve looked into corrective shapes and Extract deltas script from brave rabbit does a good job at extracting the corrective shape - skin cluster.

Also that blend shape issue is kind of solved (temporary solution) for the moment. Earlier my blend shape node was below the skin cluster node in the inputs. I moved the blend shape node to the top and it works. My joint controls won’t move with the blend shapes for but it works for now. I will try and solve this and find a better solution for this.

Also i learned today that alembics can be imported in unreal. I exported a lattice deformed mesh alembic today to unreal and it works just fine. The only problem is that it doesn’t import materials(shaders) properly. Does anyone have any experience with importing alembics into unreal. That would also be really helpful as we riggers won’t be bound to the limitations of joints anymore for game engines.

Thanks for the help guys.