Blend Shape and Ncloth

I’ve been testing with blend shape trying to use babylon exporter

I took a simple sphere and modeled a “star”,


But when exporting the blendshape animation it didn’t work. I tried two ways, using set drive key and keying directly in the channel box, none of the options worked.
Is there any trick to make it work?

Another question I have is, is it possible or there’s a way to use ncloth for babylon to mesh separate character clothes following the animation? Currently I make the clothes and the character mesh in the same mesh to animate.

Pinging @PatrickRyan

@Hugo_Dalben, I put together a simple playground for you showing our morph target implementation. The thing you need to make sure of when you work with blend shapes in Maya is that you do not delete the blend shape target meshes from the scene. Maya will allow you to delete these meshes as it writes the triangle list of the targets into the Maya file, but when we export the file, the Babylon exporter needs to have access to these target meshes to write their triangle list into the glTF file.

You can then export only selected meshes with your final mesh selected so that you don’t write the blend shape targets as meshes in the glTF file. We are only interested in their triangle list, not the actual mesh.

image

Note that I have exported normals for the morph targets but not tangents. You can also export the tangents if you see some rendering errors in your mesh in case the calculated tangents are not the same as those in Maya, but I rarely see the need to take on the extra tangent data in the glTF file as the calculated tangents are usually fine.

In terms of nCloth in Babylon, this is not an easy or straightforward thing. Since nCloth is a vertex simulation in Maya, we have no way to export this data and glTF has no concept of either mesh streaming or positional data streaming. If you want to use nCloth to do a simulation that is then skinned to a skeleton, you can do that. Or if you want to do a few simulations on the cloth that is skinned to a skeleton, that is also possible because you can mix skinned animation and morph target animation on the same mesh. So you could simulate some different folds at the extreme ends of the motion and morph between them. You can use several morphs for your cloth simulations, but beware that you need to target WebGL2+. We also have a video series using high numbers of morph targets which is Blender based, but a lot of the concepts will be the same even if the path in Maya is different.

There is a lot of interest in realistic cloth simulation coming from the e-commerce sector for viewing products in 3D, but there are no solutions yet beyond simple soft body physics.

I hope this helps, but let me know if you have any other questions.

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fyi @Guillaume_Pelletier

Maya and Max exporter are now suppose to manage to rebuild the target, using the delta informations stored into memory and available throught SDK. However, Maya 2022 is marked as SDK major changes and i beleive these informations access has been modified. I will have a check.