Description

The WeightBuffer passed to the shader does not reflect the SkinWeightProfile.

The work around is :

void FOptimusSkinWeightsAsVertexMaskDataProviderProxy::GatherDispatchData(FDispatchData const& InDispatchData)
{
	const int32 LodIndex = SkeletalMeshObject->GetLOD();
	FSkeletalMeshRenderData const& SkeletalMeshRenderData = SkeletalMeshObject->GetSkeletalMeshRenderData();
	FSkeletalMeshLODRenderData const* LodRenderData = &SkeletalMeshRenderData.LODRenderData[LodIndex];

	FRHIShaderResourceView* NullSRVBinding = GWhiteVertexBufferWithSRV->ShaderResourceViewRHI.GetReference();
	
	FSkinWeightVertexBuffer const* WeightBuffer = LodRenderData->GetSkinWeightVertexBuffer();
//work around begins
	if (LodRenderData->SkinWeightProfilesData.ContainsProfile(SkinWeightProfile))
	{
		const FSkinWeightProfileStack ProfileStack{ SkinWeightProfile };
		WeightBuffer = LodRenderData->SkinWeightProfilesData.GetOverrideBuffer(ProfileStack);
	}
//works around ends
	check(WeightBuffer != nullptr);
Steps to Reproduce
  1. Download and open the repro project from the EPS case linked in the "Additional Info URL".
  2. Confirm that the skeletal mesh DG_SkinWeightProfileTest/Cylinder has a skin weight profile named profileB.
    -The default profile has influence on joint3.
    -profileB has no influence on joint3, but instead has influence on joint7 and joint8.
  1. Open the deformer graph asset DG_SWP_profileB.
  2. Check the SkinWeightsAsVertexMask node and make sure that:
    -The Skin Weight Profile property is set to profileB.
    -The Bone property is set to joint3.
  1. The output of this node is baked into the output skeletal mesh as vertex color.
  1. See the level viewport 

Result:

Although profileB has no influence on joint3, influence on joint3 is still rendered.

Expected Result:

Since profileB has no influence on joint3, the mesh should be rendered in black

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Unresolved
ComponentUE - Anim - Rigging - Deformer
Affects Versions5.6
Target Fix5.7
CreatedAug 1, 2025
UpdatedAug 7, 2025
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