# Substrate material in NvRTX 5.4 version with ReSTIR

**URL:** <https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715>\
**Category:** Unreal\
**Created:** [December 22, 2024, 9:03pm UTC](https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715 "2024-12-22T21:03:51Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![marcel.vicic](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@marcel.vicic](https://forums.developer.nvidia.com/u/marcel.vicic)\
**Post date:** [December 22, 2024, 9:03pm UTC](https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715/1 "2024-12-22T21:03:51Z")

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Hello,

I’ve tried to run the latest NvRTX 5.4 branch with ReSTIR GI but when i try to enable Substrate materials I get the “FComputeSurfaceComplexity’s required shader parameter FParameters::SceneTextures::GBufferATexture was not set.” error.

Did anyone find any workaround this error?

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**Author:** ![nate12](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@nate12](https://forums.developer.nvidia.com/u/nate12)\
**Post date:** [December 25, 2024, 5:47pm UTC](https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715/2 "2024-12-25T17:47:52Z")

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Same problem. Would love to use these features but unable to run both ReSTIR and substrate materials.

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**Author:** ![marcel.vicic](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@marcel.vicic](https://forums.developer.nvidia.com/u/marcel.vicic)\
**Post date:** [December 29, 2024, 4:53pm UTC](https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715/3 "2024-12-29T16:53:42Z")

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I’ve found the likely cause for the issue, but I haven’t a clue how to fix it. The problem is that substrate changes how the FGBufferData works. As in pbr workflow FGBufferData has GBuffer textures for all maps, whereas substrate only uses GBuffer texture in anisotropic data and InMRT1 (which i don’t know what exactly is). So basically ReSTIR tries to read the substrate FGBufferData like it read the pbr FGBufferData and it fails.

I don’t know how to fix any of this but if someone knows a workaround or a fix I would really love to try it!

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**Author:** ![eric.swarts](https://developer.download.nvidia.com/images/forums/profile-default-devtalk-84.png) [@eric.swarts](https://forums.developer.nvidia.com/u/eric.swarts)\
**Post date:** [January 9, 2025, 2:14pm UTC](https://forums.developer.nvidia.com/t/substrate-material-in-nvrtx-5-4-version-with-restir/317715/4 "2025-01-09T14:14:46Z")

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Encountering this issue now myself. Any updates on if anyone here was able to find a solution?