# Mesh property is suddenly undefined

**URL:** <https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301>\
**Category:** Bugs\
**Tags:** mesh\
**Created:** [June 13, 2024, 1:24pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301 "2024-06-13T13:24:21Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Joe\_Kerr](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/joe_kerr/32/39017_2.png) [@Joe\_Kerr](https://forum.babylonjs.com/u/Joe_Kerr)\
**Post date:** [June 13, 2024, 1:24pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301/1 "2024-06-13T13:24:21Z")

</div>

Hi everyone,

Mesh.overrideMaterialSideOrientation is undefined. I have not updated my local project yet. But from what I see in the playground: [Babylon.js Playground](https://playground.babylonjs.com/#QTBLDT) (throws in v7, works in v6)

Not good. Could be related to this:

```auto
//https://github.com/BabylonJS/Babylon.js/blob/master/CHANGELOG.md
Improve clarity about how mesh.sideOrientation works - [New Feature] by deltakosh (#15189)

```

```auto
//https://github.com/BabylonJS/Babylon.js/releases
#15189: Improve clarity about how mesh.sideOrientation works

```

```auto
//https://github.com/BabylonJS/Babylon.js/pull/15189/
There, I see "breaking change" as a second label.

```

May I please ask for confirmation that this is an intended breaking change?

Best wishes  
Joe

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<div class="post-metadata">

**Author:** ![RaananW](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/raananw/32/28955_2.png) [@RaananW](https://forum.babylonjs.com/u/RaananW)\
**Post date:** [June 13, 2024, 1:51pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301/2 "2024-06-13T13:51:48Z")

</div>

CC @Deltakosh , this is related to a PR merged yesterday - [Improve clarity about how mesh.sideOrientation works by deltakosh · Pull Request #15189 · BabylonJS/Babylon.js (github.com)](https://github.com/BabylonJS/Babylon.js/pull/15189) (which you are referencing in your message)

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<div class="post-metadata">

**Author:** ![Deltakosh](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/deltakosh/32/26635_2.png) [@Deltakosh](https://forum.babylonjs.com/u/Deltakosh)\
**Post date:** [June 13, 2024, 2:07pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301/3 "2024-06-13T14:07:47Z")

</div>

Yes it is! I will document it today.

New name is simply sideOrientation

May I ask what is your use case? Why do you need it?

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<div class="post-metadata">

**Author:** ![Deltakosh](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/deltakosh/32/26635_2.png) [@Deltakosh](https://forum.babylonjs.com/u/Deltakosh)\
**Post date:** [June 13, 2024, 2:09pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301/4 "2024-06-13T14:09:53Z")

</div>

Btw if it is a problem I can keep the previous one and flag it as deprecated

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<div class="post-metadata">

**Author:** ![Deltakosh](https://sea2.discourse-cdn.com/flex024/user_avatar/forum.babylonjs.com/deltakosh/32/26635_2.png) [@Deltakosh](https://forum.babylonjs.com/u/Deltakosh)\
**Post date:** [June 13, 2024, 3:11pm UTC](https://forum.babylonjs.com/t/mesh-property-is-suddenly-undefined/51301/5 "2024-06-13T15:11:42Z")

</div>

Here is the updated doc page:  
[Babylon.js Breaking Changes | Babylon.js Documentation (babylonjs.com)](https://doc.babylonjs.com/breaking-changes)