Skinned Mesh with blendshapes not showing on build/simulator

Hello, I am building a very simple bonded mixed reality scene. I managed to have a functional build running on the headset with just a rotating cube, however, my second build, which use a cube with a blendshape exported from blender, has the cube not being rendered at all, neither in the build nor in the simulator.

Skinned meshes without blendshapes work.

Is this a known issue? Or am I missing a specific settings for blendshapes?

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Unfortunately, blend shapes are not supported at this time.

Understood, thank you for the quick answer!

Following Dan’s presentation today, my understanding is that this is a limitation of RealityKit. Am I correct?

That’s correct; RealityKit has no support for blend shapes. Absent Apple adding that support, our only option for supporting blend shapes would be to perform the blending in a shader graph either by repurposing vertex attributes (which is tricky because the visionOS vertex attributes are limited in number) or by storing the blend shape vertex attributes in textures and sampling from those in the shader graph. That’s definitely something we’re considering, though, since blend shapes are turning into a somewhat commonly requested feature.

However, if you want to submit feedback to Apple suggesting that RealityKit should support blend shapes, that would certainly be helpful. :wink:

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What’s the best way to submit that feedback? Just in their forums? It’s puzzling, since their mimoji system uses blend shapes and I’m assuming their new Personas will also.

The best way is via Xcode’s Help → Provide Feedback or the Feedback Assistant app.

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Awesome, thank you. I haven’t gotten Fully Immersive VR mode to work yet but theoretically, since it doesn’t use RealityKit (?), would blend shapes work in there if they’re playing back in the editor?

Yes; since fully immersive mode uses Unity rendering, all Unity features, including blend shapes, should work.

Awesome. Thank you!

Update: With help, I got fully immersive working and yes, blend shapes do work in that mode!