How do I remove TAA jitter in global shader?

Development Rendering
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1

I’m using UE 5.5

I have a global shader that outputs to a UTextureRenderTarget2D asset which then gets used in a post-process material.

When the post-process material is set to blend to scene color after the tone-mapper there’s jittering. This same jitter can be found in the render target result that is used which suggests that I need to cancel the jitter out in the global shader.

This is what I have in my .usf, subtracting the jitter doesn’t seem to do anything.

ViewState View = ResolveView();
const float2 PixelPosUV = SvPosition.xy * View.BufferSizeAndInvSize.zw;
const float2 JitterUVOffset = View.TemporalAAJitter.xy;
const FScreenSpaceData Data = GetScreenSpaceData(PixelPosUV - JitterUVOffset, false);

I can confirm that the jitter variable does have values within the 1px UV range for the render resolution.

It’s just this specific scenario that I have the problem with and would like to correct.

2

Hi, did you ever found a fix for the scene color after tone mapper having jitter, I don,t wanna move to before DOF, I need to stay after tone mapping for other reasons, but also encountering the issue you are having?

3

Hey, unfortunately I haven’t, I ended up shelving the issue for now and basically just operate on the idea that if you’re using the RT, don’t use it after the tone-mapper which sucks since I would have thought it would be easy enough to cancel out the jitter.

Edit: Playing around, even pulling in the jitter from the FViewInfo.TemporalJitterPixels derived from the FSceneView that gets passed into the scene view extension does nothing even though it has a value. It doesn’t matter what combination I use when adjusting the current pixel or uv position