Mobile Auto-Instancing + World Position Offset.. bug?

Development Rendering
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When a Static Mesh has a Material with “World Position Offset” instructions it will disable Auto Instancing on Mobile.

I’m hoping this is a bug?

To reproduce:

Enable Auto-Instancing on mobile through this setup:

r.Mobile.SupportGPUScene=1
r.Mobile.UseGPUSceneTexture=1

  • Fill an empty level with 100 spheres and a basic material
  • Turn on Android Vulkan preview platform (settings gear icon top right of unreal editor)
  • Use stat RHI to view the draw call count
  • Draw count should be low (approx. 200-400 ish)
  • Change the material to have some form of world position offset
  • Auto-instancing will now be disabled for all spheres, draw count increased to 2500+

Turn off Android Vulkan preview platform back to PC, draw count will go back down to 200-400ish.

So on PC Auto-Instancing works with a material that has World Position Offset. I’m hoping this is possible for mobile in the future!

P.S. It would be great if HISM PerInstanceRandom and PerInstanceCustomData were also supported on Mobile!

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