TAA and Motion Blur causing noisy aliasing on non moving bones of skeletal mesh


I have problem with both TAA as well as MB causing very odd noisy aliasing on parts of skeletal mesh that do not move relative to the world.

I have a tank vehicle as a single skeletal mesh with turret being animated as a bone of this skeletal mesh. Turret is following the direction of the mouse cursor, here’s a blueprint: TankBP.JPG

Now, whenever I turn the tank around and keep the turret static, I get this really weird noisy aliasing. Part of it seems to be caused by TAA and other part by MB, because:

TAA+MB = noisy aliasing
TAA without MB = noisy aliasing
FXAA without MB = fine, no issues
FXAA+MB = noisy aliasing

I have created a video here:

I will be extremely thankful to anyone who can help me. I am thinking, perhaps, if the tank and the turret were a separate static meshes, instead of one skeletal mesh, could that help? Or can the way I am rotating the turret in the blueprint influence this?

If necessary, I am willing to give up MB for my game, although I won’t be happy about that. I don’t want to give up TAA though.

Thank you very much in advance.

Alright, so I found that indeed there is a difference between how animated static mesh components are handled compared vs how the manually animated skeletal mesh bones are rendered.

When I re-make the same setup with tank built out of multiple static mesh components instead of one skeletal mesh component, it renders all fine. Furthermore, there seems to be a skeletal mesh component property, called “Per Bone Motion Blur”: which seems to be present specifically to solve this, but it does not seem to help at all.

Here’s a video of the difference

I still hope someone who knows more about this would chime in. I am really interested as to why this is happening and how can I avoid it in the future.

Thank you.

I do not have a solution for this, but I can say I’m definitely noticing this myself. Every component I attach in blueprints appears blurry and there doesn’t seem to be a solution, save for turning off motion blur in post process all together?

Is this also present in the latest engine preview ?
and maybe it is actually related… In .24 the cloth sim on paragon twinblast is blurring out as you move very similarly to your tank. I figured it was a cloth bug of some sort / didn’t bother investigating.

I’m doing some digging on similar path. On the C++ side of things, we have these functions but I can’t say either way if it would help…

I am also fighting with Poseable Mesh Component to follow physics based bodies, and then on to sorting out proper motion blur for it after that.

This thread has been made long time ago. Since then I’ve reported it as a bug and the bug should be already fixed. So if you are experiencing similar issue, it’s probably not the same thing.