Unreal Engine Issues

Niagara NDC GPU Instance Counter leak

In NiagaraDataChannelData.cpp, FNiagaraDataChannelDataProxy::EndFrame enqueues a GPU readback for each entry in PendingGPUReadbackBuffers, but the corresponding FNiagaraGPUInstanceCountManager::Free ...

Wrong calculation of "MaxAllocatedCountEstimate" inside FNiagaraRendererRibbons::GenerateDynamicData()

Starting with UE 5.4, function FNiagaraRendererRibbons::GenerateDynamicData() from file [NiagaraRendererRibbons.cpp] attempts to calculate DynamicData->MaxAllocatedCountEstimate as such: DynamicDat ...

NDC Sorting Incorrect

Using the new NDC BP nodes in 5.7 causes sorting to break; one system, regardless of world placement, is always drawn over the other. Even when the viewpoint puts the dominant system in the foregrou ...

Potential wrong branch condition about DFAO and Niagara GPU SDF Collision

Particles using Distance Field collision can have their collision controlled by "r.DistanceFieldAO". It appears that the condition in "ShouldPrepareGlobalDistanceField(...)" from DistanceFieldAmbie ...

Niagara module "Beam Emitter Setup" makes attribute Emitter.BeamID flick between -1 and LoopCount every frame

When working with beam and ribbon effects in Niagara, Emitter.BeamID is used to fill Particles.RibbonID so that a looping emitter can spawn multiple discrete beams. Emitter.BeamID is assigned by mod ...

Niagara GPU Distance Field collision uses only the first view in split-screen, causing collision to drop out for other players when view 0 loses Global DF coverage

In split-screen, Niagara GPU Distance Field collision appears to be evaluated against only the first view passed into the Niagara GPU sim (view index 0), rather than per split-screen view. Because G ...

DynamicMaterialParameters Niagara module resets write flags on emitter update

When using the DynamicMaterialParameters Niagara module in UE 5.6, 5.7, and UE5-Main (CL 50298778), updating an emitter causes Boolean values, such as Index0Float0Write, to reset to default values, ...

Niagara: MeshParameterBinding property of the StaticMeshLocation module does not accept binding to parameters of type StaticMesh.

On the details panel of the StaticMeshLocation module, when expanding the dropdown of the MeshParameterBinding property, user parameters of type StaticMesh don't show up (only those of type "Object" ...

Issue with Niagara emitter inheritance

Modules in the particle spawn stage get unlocked and lose inheritance after changing the inherited emitter's interpolated spawn mode to "No Interpolation" then resetting. ...

Niagara problem with "Static Mesh Location" module