Hello, I’m trying to create a large scene relying purely on dynamic lighting (as its an arch/viz project, there is a lot of interest in a faster workflow, cutting out UV mapping) so I’m currently using Light Propagation Volumes and Distant fields etc, but i can’t find how to get some of the shadows to have a better resolution.
Heres an example of a shadow from a roof light. How do I get straighter lines? I’m sure it’s something fairly obvious I’m missing…
Hi Espii,
If you’re using Distance Fields Shadows the shadow resolution for the generated distance field mesh will depend on the resolution of the said distance field mesh. By default these use a resolution of 1, which for some meshes with more complex geometry can cause issues like you’re seeing.
Here is a sample image of a test asset with more rounded geometry:
To increase the resolution you can open the Static Mesh in its Static Mesh Editor and then in the details panel on the right you will see the Build Settings. You’ll want to adjust the Distance Field Resolution setting. Only adjust it incrementally (ie. 1, 2, 3, etc) so that you only use the maximum resolution that gives you the best results, otherwise it’s overkill and a wait of volume texture memory.
Keep in mind that this may not work for every type of mesh. It’s better to use a combination of both Cascaded Shadows (default dynamic shadowing method) and Distance Field Shadows.
You can keep a low distance, like 500 (5m) or 1000 (10m) to keep nice shadows up close and use the distance fields for further out shadows. The method was used in the Kite World Demo that Epic released back in March.
I hope this has helped.
Tim
Thanks, thats helped with some of them, however it seems when up close to some of the shadows (inside the dynamic shadow distance) there’s still the same problem? are there settings with the cascaded shadows that can help?
I’ve found I can improve them by reducing the ‘Dynamic Shadow Distance Movable Light’ value down, however it seems like the Mesh Distance fields I’m using are all terrible, so they produce a lot of funky effects…
I’m not sure these are particually fixable as there are a lot of meshes… I guess as lots of the mesh data is imported weirdly, the distance field meshs are also messed. any ideas?
These images aren’t as helpful as having a look at the Mesh Distance Field view in the Show section of the viewport drop downs. If you need to troubleshoot distance field issues this is the view you need to be in to see what’s going on since the distance field shadow is just a representation of this mesh.
By default your directional dynamic light will have a set distance (20000). I was under the assumption you had disabled this and set it to 0 to only use distance fields as the shadowing method.
Have a look at our wiki guide for dynamic lighting. It can walk through some of the adjustments to get better dynamic shadows. A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums
Still with Distance Fields there are going to be limitations based on scaling of the mesh, whether it’s non-uniform scaling or not, and the size of the mesh, since distance fields aren’t meant for really large meshes. You can read more about the limitations between distance fields in both of these pages. Even though they are separate distance field techniques they limitations apply to both really methods really.
