I noticed that the landscape is taking a lot of time in raytracing dynamic geometry, even when I remove displacement.
I don’t want to set “r.RayTracing.Geometry.Landscape” to zero to avoid visual artifacts.
I’d like a static BLAS, build once, like a static mesh.
Should I duplicate my landscape, convert into a static mesh just for the raytracing scene?
Or is something engine side coming to avoid paying that cost for landscape?
Hello, this is a known issue with some more details provided here: [Content removed]
Updating landscape continually is a way to avoid divergence between BLAS and landscape in general as its geometry gets streamed in/out.
For now you can set r.RayTracing.Geometry.Landscape.LODsUpdateEveryFrame=-1 and increase r.RayTracing.Geometry.Landscape.FractionalLODUpdateThreshold to workaround this issue but you will likely see dark splotches on the landscape.
It looks like we’ve made additional changes in 5.8 and beyond for Nanite ray tracing including landscape, and I’ve reached out to the team about those plans and if the state in 5.8.
Are you using Nanite landscapes and do you plan to upgrade beyond 5.7?
What will be the way to have no artifacts and not have the landscape considered as a dynamic geometry?
Without Nanite raytracing - which will mature in UE 6.x and isn’t considered game ready in 5.8 - the only way to avoid artifacts is to update the RT geometry to match the rendered geometry when the LOD changes and that is through the existing dynamic geometry path which can be controlled as mentioned above.
Another caveat of the Nanite raytracing path is that it will require more memory which likely will not fit into the budget of current gen consoles or PC GPUs at our current 8GB spec.
We are indeed using Nanite landscapes and plan to upgrade to 5.8.
What will be the way to have no artifacts and not have the landscape considered as a dynamic geometry?