Hey ,
I have a few questions so I can gather the information needed to test and verify this issue on my end. You mention this occurs on all your assets. When lighting a translucent object, the lighting information received is based on vertex count of the mesh. This means even if you tessellate your material, the lighting will still have a square look if your vertex count is low on your mesh. A couple of quick questions:
- What is the vertex count of the plane/mesh you are using in the images provided?
- What are your settings for the Spot Light actor illuminating the mesh from the underside?
- More specifically, did you uncheck the ‘Use Inverse Square Falloff’ option?
Inverse Square Falloff
Take a look at this documentation which could have some helpful information on your issue as well. Also, as a quick note, since all lights are applied deferred in Unreal Engine 4, as opposed to the forward lighting path used in Unreal Engine 3, materials write out their attributes into the GBuffers, and lighting passes read in the per-pixel material properties and perform lighting with them. Therefore, having the lighting volume (assuming you are talking about lightmass importance volume) attached to the player will not have any visual effect on the lighting while playing.
Let me know if you have any other questions or need further assistance.
Thank you,