Unreal Engine Issues

Parameter distributions can be reset to None in Cascade Particle Systems, causing Cascade to Niagara conversion to crash the editor.

Cascade to Niagara conversion causes the editor to crash due to any distribution parameter in the Particle Emitter being reset to none. Repro Rate: 4/4 Tested this in //UE4/Release-4.27 @ CL# 1831 ...

Pressing the focus key twice in a Niagara System's preview window causes the preview to lose orbit around the system when moving

Pressing the focus key twice in a Niagara System's preview window causes the preview to lose orbit around the system. Upon pressing the focus key again, the orbit remains lost. Alt + Left-Click also ...

Niagara particles with collision will continue to move along World +Y-axis

Niagara particles with collision slide in the direction of World +Y-axis after the point they should have stopped. If the user uses multiple systems in the same spot all the emitters appear to bounc ...

Adding a Structure BP parameter with a Enum BP as a member to a Niagara Module Script crashes the engine

Adding a parameter of type structure bp which references an enum as a value to a module script crashes the engine. This issue is also occurring in 4.27. ...

Override Parameters in the details section of the editor do not slice smoothly when dragging with mouse

Sliding a value within the override parameters in the details panel of the editor, the slider will get "stuck" after sliding to one value and it stops working. This occurs with any slider within the ...

When saving an emitter in the Niagara system as an asset, it crashes when overwriting an existing emitter.

Selecting a material name for a Skeletal Mesh Sampling region can crash the editor

The editor will crash when clicking on the Material Name selection box a second time. It appears this triggers another selection change with a null input, which crashes the editor. ...

Compile errors in GPU scripts aren't always reported to the Niagara Log

The Niagara log will not always show compilation errors for GPU particles. The errors are visible in the output log. ...

Crash when calling SetVector2DParameter on a Niagara Parameter Collection

Crash when calling SetVector2DParameter on a Niagara Parameter Collection. The value for the SetVector2DParameter may or may not have to be changed in order for the crash to occur.  Assertion faile ...

Niagara : incorrect rendering on D3D12 when rendering a very large number of meshes

The input argument of DrawIndirect for Niagara meshes, which is made by ComputeShader, may be invalid. This problem does not appear with -onethread command line option. ...