UPDATE/ Tim’s solution works partially. Still have a problem with pipes. Unfortunatelly, those settings doesn’t affect pipes at all 
Hi!
English isn’t my motherlanguage so I’ll try to explain it as simple as I can.
I’m building an modular enviroment in UE 4.8 and the pieces seem to be randomly rendered little darker or lighter than others. Just take a look at those screenshots (especially flooring, wall with windows and pipes) :
As you can see in some places they’re tiling nicely, in the others - they’re not. Last screenshot shows a new scene with the same assets as in main scene and lights from UE default scene - it works.
As regards to the pipes, they’re the biggest problem. Whole pipe system is a blueprint based on tutorial below and I don’t know why it renders that bad (few of them are like overexposed, the others underexposed and it happens randomly apart from lights position).
I’ve doubled checked that every asset stays on the grid, I’ve tried to enlarge lightmaps (even to some horrifying resolution like 512 for a simple wall piece), bake lights in different quality and I have run out of the ideas what’s wrong.
Scene is lighten with 17 static point lights (they’re placed in every lamp). Every one of them cast shadows and affects world. Except lights and static meshes there’re:
- 9 Screen Reflection Capture
- Sky Light
- few bsp boxes for ceiling
- Sky Sphere
- Atmospheric Fog
- Splines
Please, someone help me.
Hi Psuja,
Have a look at this thread on the forums: Modular Asset Lighting Problem - Rendering - Epic Developer Community Forums
When lighting is built the assets are will be using different threads for the lighting calculations that can cause the difference in shading between modular pieces like this.
Using the thread above you can see how to reduce this artifact of indirect lighting.
Ideally as well, overly using modular pieces is not generally the best approach. You would want to break the rooms up into larger pieces rather than a bunch of smaller ones that have to be loaded each time. This can help reduce draw call count as well.
I hope this helps.
Tim
It successfully minimize the effect on walls and floor, but I still have problem with pipes. Those lighting settings doesn’t affect their look at all. I don’t know what’s wrong… Any ideas?
BTW My settings were:
- Light Build Quality: Production
- Static Lighting Level Scale = 1.0
- Indirect Lighting Quality = 2.0
- Indirect Lighting Smoothness = 0.6
- Environment Color = 0.1;0.1;0.1;1.0
That solution is not going to work in all cases, so this is largely expected. The problem right now is how indirect lighting is handled on different threads for different objects in the scene, so ideally you would be able to set groups of meshes that get calculated together or other ways so that this can be handled in UE4. This may be improved in the future, but it’s not something that I see being handled in the short term really.
This can be minimized further by snapping hard edges to a grid spacing setup in your UV Channel 1 in your modeling program when you are creating the UV.
For instance, If you have a wall with the 4 hard edges for a single face. You would first setup a grid with a target lightmap resolution. So if you target 128 you would do the calculation 1 / n = grid spacing or in this example 1 / 128 = 0.0078125. You would then take the 4 edges and snap to the grid with a 2 spacing between either UV island to limit light bleed.
Even still, this doesn’t guarantee it will get rid of the seams. This is where other geometry comes in to mask the artifact. It’s just a matter or working around what you’ve got to work with this.
