Strange warning with blend shapes

Community USD
1

UPDATE: I restarted Omniverse and the warnings went away without any other changes, so probably a memory corruption. So this can probably be ignored!

ORIGINAL POST:
I have a model (with skeleton) with multiple meshes. Different meshes (face skin, eye lashes, ears, body skin, etc) have different numbers of blend shapes. E.g. the body does not have ARKit blend shapes defined as they are only relevant to the face. Eye lashes don’t define jaw open blend shapes.

Then the animation clip morphs a set of blend shapes (ARKit blend shapes).

So the weights have an array of 51 values (the blendShapes and blendShapeWeights attributes of SkelAnimation prim), and the different meshes have between 0 to 123 blend shapes (defined by skel:blendShpaes and skel:blendShapeTargets).

My reading of Universal Scene Description: Schemas In-Depth makes me believe this is okay. It matches up on the names, then uses the weights based on those mappings, defined per mesh.

Here is an example from the docs that seems to support this:

def Skeleton "Skel" {}
 
def SkelAnimation "Anim"
{
    uniform token[] blendShapes = ["A","B","C","D"]
    float[] blendShapeWeights = [1,0.75,0,0]
}
 
def Mesh "Mesh (
    prepend apiSchemas = ["SkelBindingAPI"]
)
{
    def BlendShape "Foo" {}
    def BlendShape "Bar" {}
 
    uniform token[] skel:blendShapes = ["B", "A"]
    rel skel:blendShapeTargets = [<Foo>, <Bar>]
 
    rel skel:skeleton = </Skel>
    rel skel:animationSource = </Anim>
}

In the example from the docs, note that the blend shapes in the SkelAnimation do not match the number of blend shapes in the Mesh, which is what I am doing. (However, I have many meshes, not just one.)

My concern is I am getting warnings in Omniverse, so wanted to check I am doing the right thing:

2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [8]
2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [32]
2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [62]
2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [8]
2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [108]
2024-01-17 02:28:15  [Warning] [omni.usd] Warning (secondary thread): in ComputeSubShapeWeights at line 289 of W:\ac88d7d902b57417\USD\pxr\usd\usdSkel\blendShapeQuery.cpp -- Size of weights [51] != number of blend shapes [45]

Is this just warning because the blend shapes defined and the array of weights don’t perfectly align? That is, I can ignore it?

2

Thanks much for the update, @alankent !