Distance Field Shadow Strength? and DFAO Distance?

Development Rendering
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1

Hi,

I have two questions regarding DFAO and especially Distance Field Shadows:

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  1. Is it possible to adjust the strength of the Distance Field Shadows? Because as you can see in the image (above and below) the distance field shadow from the Billboard LOD is darker/stronger than the cascaded shadow. So far I already tried adjusting the “Self Shadow Bias” in the Mesh Settings, as well as the “Ray Start Offset Depth Scale”, the first one did not change much unfortunately (I guess this affects complex meshes like rock-cliffs more) and the second one had an effect but with the drawback that it affected the overall look to much (e.g. loss of shadows in the distance).

I also tried using the Pixel Depth Offset in the billboard material (as suggested on the official Unreal documentation), but I am not sure if I am using it correctly. Do I only have to input a scalar value for the Pixel Depth Offset to make this work?

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  1. Is it possible to adjust the distances how far DFAO is being shown/rendered? Or when it starts/ends?

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Or would you have any suggestions how to deal with those two issues?

Thanks :slight_smile:

2

Just in case others come across this problem.

To adjust Strength of Distance Field Shadows

Try these three things:

  1. In Skylight Check Min Occlusion and try adjusting this up. I find anywhere form .2-.45 to get much better results.
    The lower you can keep this, the less you’ll blow out your DFAO shadows.

  2. On the mesh assets themselves themselves go and up the “Distance Field Resolution Scale” (you have to do this per LOD). Even a small increase can have a big impact (going from just 1 → 2). You will pay an increased memory cost though.

  3. Either in the mesh asset or in the world change the “Self Shadow Bias” up. I find that around 7-8 starts to have a noticeable affect.

  4. In your post process volume check out your ambient occlusion settings. AO and DFAO can stack in weird ways.

I do not have an answer for draw distance of DFAO and am still looking for that answer.