Hey im very new to using UE5 and shadow/rendering and im using it for education purpose.
Im testing around with building with meshes and noticed that the meshes cast shadows within it
and i try to make it so it will only cast shadow from the outside of the mesh but i dont know how to do it.
Does anyone have ideas/feedback on how to fix it
Hi, it doesn’t look like shadows, but like distance field ambient occlusion from a movable skylight. I think you can disable it by setting the global illumination quality to 0 in the console, and likely also by setting the Occlusion Max Distance to 0 in the skylight.
I tried your solution and it looks like setting max distance to 0 removed the shadows inside the mesh but setting quality to 0 made the rock walls look blend and flat
but setting quality to 0 made the rock walls look blend and flat
Yeah, I don’t think you can have one without the other. You could do this blueprint based, so when the camera is inside the mesh then blend the max distance to 0, and when the camera is outside the mesh blend it to 1000 again.
You can also disable ‘Affect Distance Field Lighting’ per mesh (in the settings), so that you disable it for one specific mesh but keep it for the others.
Or avoid being inside a mesh. If this should be something like a tunnel, then you could/would need to build it out of several meshes to avoid being inside a mesh.
oh no its not a tunnel. i maybe was bad at explaning but the meshes are walls surrounding the play area and when i tried it i noticed in gpu profile that a lot of ShadowDepths take up process and when i saw the shadows inside the meshes i was thinking if it was those shadows that casue the frame drops
For reducing shadow cost, ue5 currently has mainly two different ways of shadows (you can change between the two in the project settings). One is virtual shadow maps, which is the new unified way, the other is shadow maps which combines different methods. Virtual shadow maps is generally heavier on performace, and performance really goes down if the objects are not static (i.e. virtual shadow maps relies on caching the shadows) or non nanite.
For shadow maps, performance goes down if the meshes are high poly (e.g. if you use shadow maps and those cliffs are very high poly, it will perform poorly and virtual shadow maps with nanite would likely perform better there). You could switch to distance field shadows though in the directional light (set the cascaded shadow distance to 0 and then enable distance field shadows), those are also static but should be cheapest. You could then also use capsule shadows for skeletal meshes.
And for small things like grass you can use contact shadows (screen space post processing effect) which is very cheap.
And then there are some settings in the directional light for shadow maps, as well as lots of console variables for virtual shadow maps.
