Animation problems with nostrils and chin


(Ravenking99) #1

Hi sketchfab. I imported my blender model with shape key animation. I only added eyelid blinking motion and my model's other vertices are affected: nostrils and chin. Please help.



Sorry for the delay, I'm investigating.


(The Timeburner) #4

Not just the Chin and nostrils. Also the ears.
When I turn on the wireframes. No vertices are moving,aside from the vertices on the eye. Also,why is there another wireframe of another head? o.O


The vertices aren't moving, but the vertex normals are changing. No idea about the extra head.

(Ravenking99) #6

Hi James. My question is how the eye lids are changing the other vertex normals and is there anything I can do about it?

(Waleguene) #7

Hi @ravenking99,

For now, we recompute normals (with smoothing) for all morph targets, that explains the difference in normals during the animation.

When you have the original mesh (with no morph influence), normals are as you exported them, but when the animation is played and the influence of the morph target visible, we use the target's normals so the diff is visible.
The difference in the normals is dues to the way we smooth, with a crease angle.

I will look for the wireframe, it is weird..

(Ravenking99) #8

Thanks for explaining it to me.

(Jondemos) #9

Hi! Has there been any work done toward addressing this issue more generally? The strange thing I’ve noticed is that the viewer in 3D Settings has no problems with shape-deformed normals, but the standard viewer definitely does. That inconsistency led me down a comedy of errors where I would think I had fixed the problem with settings, and come back later and find it broken “again”. Eventually I realized that it was indeed a difference in how the two environments handle the shape target normal computation, and nothing I could do would fix it.

So, in addition to throwing my hat in with a years-old OP, I am pointing out that the inconsistency between the viewers causes confusion.

Here is my model, FWIW, created in Maya 2018 using the Shape Editor format of blend targets:

It would be fantastic to be able to share shape-animated characters, but as of now I can’t reliably do that.

(Waleguene) #10

Hi @jondemos,

We currently have issues with tangents in morph targets, that causes these render glitches.
The difference between both viewers is that in one case (the standard viewer) model tangents are used, but not in the other (the editor). The issue occurs when model tangents are used, as something is breaking them during the processing.

It will be fixed soon but as workaround I can suggest you to export your model without tangents/binormals, and let them being regenerated during the processing.
You should see no difference with the original model and the glitches will disappear.

Could you give and try and keep us in touch ?


(Jondemos) #11

That mostly did it, thanks!

Here’s a new version with the much improved normals: