# Is this working Distance Field Shadow?

**URL:** <https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515>\
**Category:** Rendering\
**Tags:** Shadows, distance-fields, unreal-engine, Lumen, Lighting, question\
**Created:** [April 11, 2024, 9:43am UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515 "2024-04-11T09:43:38Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![turbotanaka](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@turbotanaka](https://forums.unrealengine.com/u/turbotanaka)\
**Post date:** [April 11, 2024, 9:43am UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/1 "2024-04-11T09:43:38Z")

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I wanted to blur shadows based on distance, so I searched Distance Field Shadow. And I tried it.  
But I got a different result than what I searched for.  
I made a very tall structure and looked at the shadow at the tip and it was very sharp.

 ![image (1)](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/8/2/782c604ca15551b919a921f1e0f97a140bccb874.png)  
 ![image (2)](https://d3kjluh73b9h9o.cloudfront.net/original/4X/8/0/5/8056405b30cc3781341884c2c816287b478c9666.png)

I checked some settings.  
-cascade distance is zero  
-using Lumen and Virtual Shadow Maps  
-DirectX 12

But result is like this. am I missing some setting? or is this normal and I misunderstanding the functionality?

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**Author:** ![jblackwell](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@jblackwell](https://forums.unrealengine.com/u/jblackwell)\
**Post date:** [April 12, 2024, 5:04pm UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/2 "2024-04-12T17:04:46Z")

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So, to try to offer some clarification if I can:

1. Distance field shadows, virtual shadow maps, and Cascaded shadow maps (which use the cascade distance setting) are all _competing_ shadowing methods, and no light can have more than one enabled at a time (that is technically untrue, but it’s complicated). They don’t determine directly how soft a shadow is, just which method is used to render it (which granted, can determine how good the soft shadows look).

2. Lumen is only for indirect lighting and will not affect direct shadowing at all.

3. If by shadows blurring in the distance I’m assuming you’re talking about shadows undergoing contact hardening like they do in the real world (with a variable penumbra), then you control that by adjusting the _source radius_ of the light itself. A light that is a perfect point will have perfectly sharp shadows for optical reasons, a light that is an area will have more diffuse shadows.

4. Like I said before, different shadowing methods can create soft shadows better or worse: Hardware RT shadows are the best able to support soft shadowing, followed by distance field shadows, virtual shadow maps, and finally cascaded shadowmaps. You basically need some kind of ray-tracing to do good soft shadows.

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**Author:** ![Sebastian](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Sebastian](https://forums.unrealengine.com/u/Sebastian)\
**Post date:** [April 12, 2024, 11:58pm UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/3 "2024-04-12T23:58:08Z")

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Last time I tried, I think it was UE 5.2, raytrace shadows were doing very nice soft shadows and contact hardening, but they were having errors with foliage. I think they used the low poly version and ignore the nanite version of foliage. And I think I also read here about raytrace shadows ignoring foliage animation ?

Can raytrace shadows replace virtual shadows maps ? Or do they still have all these limitations, even in UE 5.4 ?

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**Author:** ![jblackwell](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@jblackwell](https://forums.unrealengine.com/u/jblackwell)\
**Post date:** [April 13, 2024, 2:30am UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/4 "2024-04-13T02:30:09Z")

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RT shadows can handle animated foliage as long as you tell the lights to evaluate world position offset, and enable raytracing.nanite.mode 1

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**Author:** ![turbotanaka](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@turbotanaka](https://forums.unrealengine.com/u/turbotanaka)\
**Post date:** [April 13, 2024, 6:10am UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/5 "2024-04-13T06:10:42Z")

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This answer gave me more information than Google !  
Thank you. I’ll try various things.

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**Author:** ![system](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/1/3/713c9d3f58553f0de89543d76a8a3a2779dc9fa4.png) [@system](https://forums.unrealengine.com/u/system)\
**Post date:** [May 13, 2024, 6:11am UTC](https://forums.unrealengine.com/t/is-this-working-distance-field-shadow/1798515/6 "2024-05-13T06:11:04Z")

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