Raytracing Shadow Falloff Distance, adjustable?

Development Rendering
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1

Is there any way to adjust the falloff distance for Rayraced Shadows from a Directional Light source, as with Dynamic Shadow Distance on Cascaded Shadow Maps.

There don’t appear to be any controls on either the Direct Light, Post Process or raytracing CVAR to remedy the issue. Any assistance much appreciated.

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2

I have exactly the same problem. It makes no sense. Ray Traced shadows should not benefit from distance culling. Quite the contrary actually, so I do not understand why in the world would ray traced shadows get culled with distance?

3

I’m unsure of the reasons for the Raytrace Shadow distance cull, but for anyone else curious, one answer is to utilise Distance Field Shadows.

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4

Thats not the same thing, frost.

5

Less objects to influence makes RT cheaper, not more expensive.

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No… just no… Ray Tracing doesn’t work like shadow maps, where shadow maps are generated per object. Ray tracing has the entire level geometry in the acceleration structure, and ray are traced from the camera, per pixel. So it doesn’t scale with the amount of objects but image resolution.

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Hi. Have you got any update on this topic ? I’ve tried every single command line related to rt, culling, shadows etc, but no luck.
Thanks

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This is what solved the problem for me. Hope it helps others.

r.Shadow.DistanceScale = 2

9

You Could use Contact Shadows to take over when Ray Traced Shadows culled out. It actually works much better than i expected. I am using Lumen and Virtual Shadow Maps too. HW Ray Tracing when available. For my particular scene, ‘Contact Shadows in World Space Units’ with a contact shadow length of 11 worked the best. Intensity of 1.0.
Of course, each light in the scene may very well require specific settings.
The console commands suggested had no effect for me.

My answer would be to raise the ‘Bounds Scale’ of the particular Mesh you are having problems with, though, instead of Contact Shadows.

10

Ok, it looks like the console command/CVAR

r.RayTracing.Culling 0

will allow unlimited distance for Ray Traced Shadows.
Thanks to discord user Test_1 for finding the solution

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Thanks , you are great works fine