seems like a lightmap resolution problem, but isn't...?

Hey everybody, so I just changed my lights over to completely static in the scene I’m working on: I find I’m getting much nicer bounces and everything, so I’d like to keep it that way. But my directional light is acting really weird. I’m trouble-shooting it on these two tiny posters, which I’ve quadruple-checked the UV’s on and everything; they should be good. The one on the left has a lightmap of 64, and the one on the right is cranked all the way up to 2048, if you can believe it. Obviously there’s some difference between them, but not enough to explain why the one on the right is still jacked at a ridiculous resolution like that.

And then, if you look at the one on the right much closer, you can see something weird is going on.

Are there settings besides the lightmap resolution (maybe in the directional light itself…?) that could/would effect this kind of weirdness? Thanks!

What quality setting did you build the lighting?

Medium quality, and as you can see, my lightmass settings are cranked up a little (could any of this be causing an issue?)

And the light is just a normal directional:

(the GI is cranked up in the post, as well, but the striations are still visible with it off)

Try rendering with production quality–might try reducing the Indirect Lighting Quality when doing that or you’ll get some pretty high build times.

Thanks - someone else suggested a similar brute-force angle (crank the lightmass scale down to 0.1 - yikes), but it’s a pretty simple scene. What I think it is, actually, is this effect wherein directional (or all…?) shadows soften when they get away from the caster, and since the caster in this case is on the far wall, it makes sense, actually. Is it possible to alter/disable this effect?

If you adjust the Light Source Angle in the Lightmass settings for the light that will adjust that effect.

Perfect…! Thanks so much, worked like a charm. :slight_smile:

Hi there, i am new to unreal engine, I’ve been working with unity engine for awhile, and i decided to switch to unreal engine. I’ve got some assets from unity store that i like to keep. however when i try to import them into unreal engine, importing seems fine, however, after i place it to the level, the shadow appears to be ok at first, but when i build the lighting, it displays incorrect wavy shadows. (as shown in the image). I’ve attached the properties on how i imported them. I don’t know where to post it, and didnt find much help with lightmap resolution. I even try up to 1024 light map resolution of the static meshes, but none work out.
All the global settings are default as provided by the engine.(e.g. properties of direct light source)
please let me know why is this causing. Thank you! :slight_smile:

aa4180df98312b49a2c0ec0718f1953a35397ea0.jpeg

Well that issue definitely is the lightmap resolution, if the mesh is BSP then you need to lower the number since it’s not the actual lightmap dimensions but rather tied to the number of texels per unit.

thank you for your reply.
ok, so i tried lowering the LightMap Resolution(LMR) of both mesh and geometry.
It seems to work if the layer that the shadow cast is BSP (for e.g. in the middle case, where floor [bsp] lightmap resolution is set to 4).
In First situation, floor [staticmeshactor] settings are default, except for LMR. And lowering the “overridden_Light_Map_Reso” to 4 get rid of the shadow completely, but setting to like 1024 cast almost ‘proper’ shadow as seen in the picture.
There is still a problem. When i create landscape, as seen in third situation, where the LMR is set to default value 1. Lowering to like 0.5 cast incorrect shadow, increasing it even to 2 make the scene really expensive, baking time too long and still cast incorrect shadow.
So my first issue is, how do i fix it for Third case that involve Landscape?
second issue is, will increasing LMR of Staticmeshactor make the scene expensive. i.e. open world situation
And third concern is, Increasin LMR of Staticmeshactor and Decreasing LMR of BSP really a mean to solve this problem?
thanks.
btw my engine scalability settings are set to Epic.
I’ve also attached the Project file
https://onedrive.live.com/redir?resid=A9E8ABB996B8802E!1209&authkey=!APNgWlI3Rg3l6n8&ithint=file%2Czip

ok landscape,

in landscape details panel, lighting, static lighting level of detail set to 2 and set static lighting resolution to 20, and check static shadow. you can start with a 1 and 10 setting instead of 2 and 20 to start seeing a difference on landscape shadows.

YES this will take forever… better system the less time. hope this helps some. may not be final or best but I did obsess on lighting originally and gone thru the stuff you seem to have…

I’ve been told if at all possible just use dynamic lighting you’ll get better over all shadows. but… preferences. go figure.

thanks for the solution, so i was able to resolve all the issues using dynamic lighting (directional), without having to change the lightmap resolution of anything. But using ‘Stationary light’ and for Landscape, changing the LOD to 1 and Static Lighting to 50 also solved my problem (baking time dramatically increased).
So I am just wondering which one is more cost-effective or efficient sort of for the player and the developer?
also if there are any other ways please let me know :slight_smile:

Static Lighting will always be better performance wise as you are not calculating anything in game. Dynamic Lighting is the opposite as it’s a constant calculation.

Dynamic might be very seductive at first as you develop because you don’t need to build lighting, but expect to be surprised when your game start to grow as dynamic lighting will start to eat your fps.

I will be honest with you, there isn’t any game that I care if the shadows look amazing or not as long as it’s not a stealth game where the shadows actually matter. If you look at even AAA games, you will see shadows flickering twisting around.

I would trade a better-fps gameplay to better looking shadows anyday. Make sure your shadows look okay, but don’t die on it. Static Lighting is, no matter how long does it takes to build, its a good performance improvement in the end.

OK what I see is a default material that the build lighting does not know what to do with it. (All values are zero)

Unreal 4 uses a real world lighting model so the type of material you assigned to it determines the outputted result.

A material is like making a chocolate cake. You have to have chocolate, flower, milk, and eggs and if you omit “any” of the required ingredients you won’t get a chocolate cake.

The same goes for material construction as for a material applied to an object has to “have” required ingredients so that when you build (aka bake) the lighting the real world lighting model will know what to do with the lighting energy coming off the object as part of the set number of light bounces.

I mention this as I see the use of what I would call a non-material as in that although it renderers it’s usually a material used to indicate that there is no material applied so when baked in that condition unusually results should be expected.