Lighting/Shadow Issues, UV Static Mesh Stair Wrapping, Actor Not Locking to Surface

While working on my project, I am continually having the issue of light somehow bleeding through walls when there shouldn’t be any light coming through it. Additionally, when I am far away from a shadow source the shadow seems to be broken up. This happens from only a couple of metres away and when I get closer the shadows become more pronounced. I tried increasing Lightmass to 1024 which was recommended but nothing happened. How can I make the shadows better? I am also having an issue with one of my areas where no shadows are cast from a barred entrance I had created, which I’m guessing has something to do with the Sun’s rotation (which I am also trying to figure out how to lock it at a specific time of day). My Time of Day blueprint is very basic and rotates the sun and shadows with issues like the Sun shining from underneath.

Here are some pics of lighting/shadow issues and my Time of Day blueprint:

Barred Entrance Lighting Issue

Additionally, I am having a problem with one of the stairs I have created where it comes up with a warning error after building [production] lighting where it says “NormalStairStaticMesh - Object has wrapping UV’s”. I’m not sure what a UV is but I guess it has something to do with a lightmap or something? The stairs don’t seem to collide with anything, and I don’t have any problems with the two other stairs that I have placed.

Also, I have been wondering for the longest time how I can lock the player actor to a surface like the floor at a specific height so that in Play mode I can move around the level at a specific pace without gliding around everywhere, while also being able to move up stairs as apparently there are issues with getting a player actor to move up stairs? Also, since my project will be in third-person but I started the project from scratch how can I design my own 3rd-person player actor that is able to move around in a level?

So are the problems that I’m having fixable?

Hi Icaraeus,

They are fixable, at least to some degree.

I’ve not had time to finalize and get this up on our Wiki Lighting Guide yet but you can take a look at this for adjusting the setting for your Cascaded Shadows for your Directional Light: Dropbox - Error

This will walk through what each settings does with visual examples to help illustrate.

You can also take a look at our newly created Wiki Lighting troubleshooting and tips guide here: A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums

This is being updated regularly and will have more coming very soon. It’s just a matter of finding the time to get it all up.

If you have any questions feel free to ask.


Hi Tim,

I had a look at the lighting wiki guide and tried some of the things in the guide, but I haven’t been able to solve the issue of light bleeding through walls/surfaces. I did, however, manage to make shadows lighter by repositioning the sky light I had placed but I haven’t been able to achieve anything else. I modified the DirectionalLight actor but nothing seemed to change. My settings for the Directional Light are:

Atmospheric Sun Light - Enabled
Affects World - Enabled
Cast Shadows - Enabled
Indirect Lighting Intensity - 1
Min Roughness - 0.8
Shadow Bias - 0.5
Shadow Filter Sharpen - 0.5
Cast Translucent Shadows - Enabled
Dynamic Indirect Lighting - Enabled
Cast Static Shadows - Enabled
Affect Translucent Lighting - Enabled

Should I modify Cascaded Shadow Maps? I don’t think I touched them except to increase the cascade number from 3 to 4 and I think to change the Distribution Exponent.

Dynamic Shadow Distance MovableLight - 20000
Dynamic Shadow Distance StationaryLight - 1.0
Num Dynamic Shadow Cascades - 4
Cascade Distribution Exponent - 2
Cascade Transition Fraction - 0.1
Shadow Distance Fadeout Fraction - 0
Use Inset Shadows for Movable Objects - Enabled

I haven’t touched Light Shafts or Ray-Traced Distance Field shadows. Would that change anything?