Shadows questions

Fairly new to UE4. When I build the scene with all static objects and a mix of static and stationary lights, shadows and lighting look great.

But I have an issue where I have some sliding doors set up with an level sequence cinematic. So I set up my sliding doors as movable meshes and I have a stationary light set up. But the shadows on the two sliding doors after the build look bad and not like what they did when built as static meshes.

Are there some settings that need to be applied when meshes are set to movable that I am missing to get nice shadows?

I have attached a couple of images.

  1. Image labeled (1), you see here, everything built as static meshes with a mix of static and stationary lights.
  2. Image labeled (2) you see the sliding doors with mesh set to movable, same lighting. You can see the bottom of the doors are very dark.

Found some options, trial and error, that worked. Set all lights that affect the movable objects from stationary to movable. Set movable objects to “Generate Mesh Distance Field”. Then set “Light Map Type” to True. Now the shadows of the movable objects match the static mesh shadows.

Stationary lights have static indirect lighting and shadowing, and non-baked (pre-built lightmaps) direct lighting (the first incident of light before further bouncing). So, my hypothesis is the darker area was due to direct light insufficiently bouncing inside the mesh to brighten those darker areas. Movable lights have non-baked illumination entirely, and therefore have enough bounces and coverage to lighten the mesh / scene more completely. Actually, a mesh distance field generated for the mesh would work well because it averages the shadowing from lighting calculations. And if set to two-sided distance fields (in the mesh editor settings), would most likely work better for detailed meshes (not like the one with the two sliding doors) because they’d further approximate (become more accurate and filled in) the shadows.

To get nuances and more ‘interplay’ of lights and shadowing among meshes, turn on ambient occlusion in a post process volume and place it around specific areas / meshes in the scene. Tweak settings to intensify / dull the effects of objects on one another in terms of shadowing. Check into the volumetric lightmap too, as it is capable of modifying level of detail of lighting / shadowing with the use of dynamic (movable) lights and objects, especially textured surfaces.

Hi Presto423. Thanks for the insight.