Why dont Material Function Instance parameters work? (4.21)

Material Function parameters not showing through in Material Function Instances, when used in a Material. I updated to 4.21 hoping this had been resolved, but unfortunately, not.

Does anyone have any info on this? Anyone having the same issue?

This appears to be working correctly for me. Is your material function being correctly connected to the final Material Output? If a node isn’t ultimately used, Unreal will intentionally not show that parameter. If you make sure the connections are correct and you still wont see the Function in the instance parameter, you could change parameters you want to edit in the function into "Function Input"s instead and adjust the value through the material parameter instead of a material function parameter.

I’m having a similar problem with material function instances. When I create one instance all the parameters work. When I create a second instance to use different texture parameters UE5 will not except them. They WILL NOT change from there defaults.

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Facing a similar issue in UE 5.2.1.

When adding second function instance to a material, Unreal complains "Could not resolve referenced texture ‘xyz’. and Error on property xyz.

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Running into this same issue. I’ve a second MFI that cannot resolve the textures set as parameters, yet the first version works fine. Ideas?

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Bumping this, as I’ve got the same issue in 5.3

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This problem arises due to limitations when working with functions, in particular when working with parameters. Use material layers, and you need to add layers to the material stack. There is information about this in the documentation: " All of the parameters set up here are referenced in the Layers added to the stack in a Material Instance of a base Material that is using Material Layers. This means there is no need to duplicate any of these parameters in your base Material when creating its Material Instance. When you open the Material Instance, the Layer Parameters tab displays all the Material Layers and parameters that you have added to this instance." Dock

To put it simply, new instances of functions do not make their parameters unique. You can transfer the parameters from the instance to the material and enter them with unique names, then there will be no problem.