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4.27 - Per Instance Custom Data is working with ISM but not HISM

Hi all, I have a blueprint using Per Instance Custom Data to vary a material on instanced static meshes (ISM)

When I swap out only the component type for HISM the per object custom data in the material stops working

Is this a bug?

Here’s an example using ISM you can see per instance custom data is working fine, varying tiling and features of the material

Here’s an example with HISM, the blueprint is identical, just with the ISM swapped out for an HISM. Immediately the Per Instance Custom Data in the material instances ceased to work and each instance returns to defaults material settings.

As far as i understand it, the HISM should work fine, the benefit being I can use LODs and cull instances that are not visible, but for some reason the Per Instance Custom Data simply stops working with HISM.

It was supposed to be fixed in 4.26:

https://answers.unrealengine.com/questions/973535/hierarchical-instanced-static-mesh-does-not-suppor.html?childToView=973647#answer-973647

But is currently flagged as Won't Fix:

I think this bug is related.

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Ah thanks for the quick response! It seems to be a technical limitation, reading through that thread, an issue with culling and the order of the instances?

I guess I shall have to use some kind of workaround the intended use then…

The thing is that the original poster claims it was confirmed to be fixed. Haven’t tried it since then. And now here we are :expressionless:

Yeah that is odd, I guess I’ll throw it in as a bug report and see what comes out!

Thinking about it, I assume the reason it won’t be fixed is because nanite should do the job now from UE5 onwards.

We should be able to us an ISM, and enable Nanite on the static mesh in order to gain the LOD benefits HISM would have had.