# Skeleton and Xform transforms - How do they compose, if at all?

**URL:** <https://forum.aousd.org/t/skeleton-and-xform-transforms-how-do-they-compose-if-at-all/2090>\
**Category:** USD\
**Created:** [December 19, 2024, 2:25am UTC](https://forum.aousd.org/t/skeleton-and-xform-transforms-how-do-they-compose-if-at-all/2090 "2024-12-19T02:25:25Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![deadpin](https://avatars.discourse-cdn.com/v4/letter/d/43a26b/32.png) [@deadpin](https://forum.aousd.org/u/deadpin)\
**Post date:** [December 19, 2024, 2:25am UTC](https://forum.aousd.org/t/skeleton-and-xform-transforms-how-do-they-compose-if-at-all/2090/1 "2024-12-19T02:25:26Z")

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We received a bug report where the user had roughly the following hierarchy. As far as `usdview` is concerned, it is as-if the 2 Xform transforms are ignored. Our importer however had offset the Mesh according to its hierarchy by T2 and T1 etc.

```auto
SkelRoot
    - Skeleton Foo

    - Xform with some transform T1
        - Xform with some transform T2
            - Mesh bound to Foo

```

I may have missed it but is there an indication in the documentation about how this situation should be handled?

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**Author:** ![cameronwhite](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@cameronwhite](https://forum.aousd.org/u/cameronwhite)\
**Post date:** [December 20, 2024, 10:03pm UTC](https://forum.aousd.org/t/skeleton-and-xform-transforms-how-do-they-compose-if-at-all/2090/2 "2024-12-20T22:03:50Z")

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I think this is implicitly described by [Universal Scene Description: UsdSkel Introduction](https://openusd.org/dev/api/_usd_skel__intro.html#UsdSkel_TransformSpaces) - it’s the geom bind transform which transforms the mesh’s local space points to the bind state in world space, and then the skinning transforms are applied

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<div class="post-metadata">

**Author:** ![spiff](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.aousd.org/spiff/32/22_2.png) [@spiff](https://forum.aousd.org/u/spiff)\
**Post date:** [January 6, 2025, 6:53pm UTC](https://forum.aousd.org/t/skeleton-and-xform-transforms-how-do-they-compose-if-at-all/2090/3 "2025-01-06T18:53:24Z")

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I’ve been informed by our crowds folk that we don’t rely on Xform positioning/animation in our Skel agents in our pipeline, which is not to say that it may not work, but like Cameron said, there’s definitely not a promise that it should.