I would like to get the Information stored in the GBuffer. I saw some approaches using custom HLSL nodes, e.g.:
MaterialFloat2 UV = MaterialFloat2(ScreenAlignedPosition(Parameters.ScreenPosition).xy);
FGBufferData GBData = GetGBufferData(UV, false);
return GBData.Metallic;
But I get the errors:
[SM5] /Engine/Generated/Material.ush(1271,14-19): error X3000: unrecognized identifier ‘GBData’
[SM5] /Engine/Generated/Material.ush(1271,1-12): error X3000: unrecognized identifier ‘FGBufferData’
Has anyone an idea?
1 Like
Deathrey
(DeathreyCG)
2
GetGBufferData() is defined in DeferredShadingCommon.ush.
For materials, it is only included, if material has access to scene textures, and thus, it will only work in post process or translucent materials.
Hello There!
I know that this is an old thread but…
In UE5.3, I defined a custom material node to fetch the underlying BaseColor from a Transluency Material:
FGBufferData GBData = GetGBufferData(UV, false);
return GBData.BaseColor;
when I connect the node, UE5.3 crash hard:
[2024-07-12T07:56:35.031Z]LogOutputDevice: Error: Ensure condition failed: ShaderTableHash == 0 || UniformBufferHash == ShaderTableHash [File:D:\build\++UE5\Sync\Engine\Source\Runtime\D3D12RHI\Private\D3D12Commands.cpp] [Line: 77]
[2024-07-12T07:56:35.031Z]LogOutputDevice: Error: Invalid uniform buffer FOpaqueBasePassUniformParameters bound on PixelShader at index 2.
[2024-07-12T07:56:35.031Z]LogStats: FDebug::EnsureFailed - 0.000 s
Fatal error: [File:D:\build\++UE5\Sync\Engine\Source\Runtime\RHICore\Public\RHICoreShader.h] [Line: 147]
Uniform buffer bound to slot 2 is not what the shader expected:
Bound : Uniform Buffer[FOpaqueBasePassUniformParameters] with Hash[0x09880f28]
Expected : Uniform Buffer[SceneTexturesStruct] with Hash[0x09700e08]
Shader Name : <unknown>
Layout CB Size : 2432
Layout Num Resources : 49
Resource Types : 9 8 5 8 16 16 16 16 9 8 5 8 16 16 16 16 9 8 5 8 5 8 5 8 5 8 5 8 9 8 5 8 9 8 13 13 9 9 9 9 9 9 9 8 8 8 5 8 16
Also tested:
FScreenSpaceData ScreenSpaceData = GetScreenSpaceData(UV, false);
return ScreenSpaceData.GBuffer.BaseColor;
with exact same results…
Of course, I have no idea what does this mean 
Any idea someone?
Browsing the Forum, I realise that I may have access to the SceneTexture Node in Transluent material…
And of course, it works and provide access to all GBuffer I need…
