Can't get my lighting right.

I’ve got unreal engine 4, wanted to try it out and see if it will do a better job than unity when it comes to the lighting i need. Unfortunately it has almost same issues. It does look better but I can’t tweak the settings right to make what i need. The lighting needs to suit a open world game, so a huge map with buildings and interiors but with time of day (aka day/night cycle). The idea is for the interiors to look dark but not too dark, while having the outsides look nice too. But how do i get all to work? I’ve seen this game called Player Unknown’s Battlegrounds, and it has exactly the kind of lighting i need for my project, that’s exactly what i’m looking for but i always fail and spend many hours tweaking settings that keep breaking different aspects while kind of fixing other aspects. Is there an example scene, a tutorial, anything at all that can put me in the right direction of how to achieve such lighting? Thanks in advance.

I could be wrong, but this all sounds like stuff to mess with in the auto-exposure tab within the post processing setting.

Use a directional light + a skylight, you have to use dynamic lights if the map is large or has a time of day. Though that gives you not as good of lighting for the interior, you just need some amount of interior illumination though.

I tried that before and the global illumination (or whatever it’s called in unreal) makes these shadows bleed, it just looks horrible. Maybe i needed to rebuild lighting after adding the effect though? I didn’t try that.

Yeah I’ve been using those 2 and tweaking settings. I kept directional light at moveable of course. But the skylight i tried all states and it either makes the interiors too dark or too bright. Other effects that force the light to be brighter inside actually make stuff bleed out like I said, so I don’t know what’s going on. I’ll be screenshoting different sets of settings and show you what’s on screen. I personally think the problem lays behind light bounciness when skylight is added. Because the walls have a bright texture but still the light doesn’t seem to pass through. And also, you said dynamic lights. What would you consider dynamic lights in unreal?

Sounds like you want to paint the entire scene with a single light level solution, aka Global Illumination ? By the way auto-exposure is not GI but a means to create real world eye adaptation and not used as a means in the same manner as a brightness control and why you have a lot of bleeding going on.

What you need is a way to effect the indirect lighting levels with out effecting direct lighting levels in the same manner as a brightness control does.

Luck would have it UE4 has this ability of using an HDR map as an ambient cube map available in the post processing volume.

As you see you can then increase or decrease the ambient fill with out blowing out the direct lighting. A bit of a cheat but somethings one needs a bit of help turning the dial to 11. :wink:

Hmm I’ll try that. And yes i’m trying to get everything in one pack so i can just move on from this. I’m surprised there isn’t an easy solution for this in unreal or unity without hackish ways. Thanks anyways.


I tried your method but it’s not good enough.


1 - FrankieV’s solution: Ambient intensity with custom cubemap, skylight on static.
2 - Just skylight on static.
3 - Just skylight on moveable.

EDIT: As you can see the light doesn’t realistically bounce. The hallway is quite long and that source of light should not be that strong to bounce all the way to the end of the hallway right?

If we use this HDR Ambient Light Cube Map, will it hurt the engine if we put this post processing volume over the entire level?
(outdoors level) Because that hdr tip has now fixed the dark lighting in my city map.

No need. In the volume settings uncheck “unbound” and it affects the entire scene. You don’t need to stretch it over the entire map. :slight_smile:

Well you do need a few lights to create an ambient fill from in the first place. As well there are more than one type of HDR map that you can try as well. I just used the Epic court yard as it comes with every project file but do an Internet search there are all sorts of HDR’s that you can download for free.

I mean it doesn’t matter what HDR map i use, it’s still going to equally light all places instead of giving the right effect. As i said that hallway should be pretty bright at the entrance since that’s where the light source is, and it should get darker and darker the further you look. Your method just equally lits everything, and it depends on the intensity i put it at, that’s how bright it’s gonna be, there’s nothing more to it than that.
And what do i set as mobility of my skylight anyways?

Well if you could show some examples of what you are after then I could make a few suggestions as there are tricks and tips and as to some common problems.

For example default lighting elements have their shadowing effect set to inverse so to get any kind of roll off you would have to do a lot of playing with the values by unchecking inverse as well as cast shadows you can increase the effect with out using unreasonable values. For that matter it’s a common trick to make use of two light elements once to control the local effect and the other to effect the total area you wish to effect.

Since when it comes to lighting there are 101 different ways to produce a single result what would be best is if you could supply a sample project file free from any lighting elements and a sample of what you expect as the desired effect and do a content jam kind of thing as to the different possibilities.

Based on the sample you provided I can see a few ways of doing it in theory but the result is the sum total of what is necessary as to the result that can not be done using a single lighting solution.

Come to think of it something we use to do over at 3d Buzz are challenges of setting up the situation and the challenge others to come up with possible solutions to the problem.

So in this case I’ll go first with the light the hallway challenge and see if someone else can do me one better?

Who’s in? :smiley:

I don’t really understand what you mean by using 2 different lighting elements. Do you mean use a directional light for what you called “total area you wish to effect” + a spotlight or something like that, rotated vertically to shine through the windows or something (for what you called “local effect”)? (Sorry if that’s wrong i’m really bad at this)

Okay here’s an example of what i need:

But keep in mind the lighting still has to have a functionality for day/night cycle. Directional light helps with the outside but it doesn’t magically light up interiors how i want it to do so like in the image example and that’s where i’m stuck. If this is too heavy or impossible to achieve in unreal (which i doubt it’s impossible), I will sacrifice that realistic aspect of interior lighting and just use something like your method. Maybe i don’t really know what i exactly am talking about, but really what i want is exact or close to the lighting that game PlayerUnknown’s Battlegrounds has (only difference is that they don’t have day/night cycle. I understand how that difference might be huge in terms of technicality and performance though). They have well lit exteriors and interiors of a quite big map and since i’m not an artist, i can’t really explain what i see there that makes it that perfect for what i want. I cannot extract that information from it but maybe someone else can break it down and tell me?

And I don’t think there’s a need to export my project since it’s already big, full of free packs and what not. And there’s really nothing to it, it’s just a set up scene ( a room with some furniture and windows. Also a room completely isolated from light next to it, used to test if it will get lit without a light source reaching it at all. And also there’s that hallway i showed in screenshots before. It’s a long hallway that’s open at the start and closed at the end.)

EDIT: Once again. Keep in mind this has to have a functionality for day/night cycle and also work with the outside world of the map, keeping it nicely lit. I can’t focus on one point, for example that hallway and make that work ( Even though in my case i can’t even do that without baking lights) while other aspects remain abandoned.

Btw. I think if we solve this here on the forums, it might help other people as well, as this is a pretty complex design of lighting and if we can make this, we can make pretty much most of the other designs come to life as well.

Ahhhh OK yeah I know that sample. The same trick you can us in 3ds Max of using an omni-light in as an ambient fill is whats happening here.

Easier to show whats going on than to write it out.

Player unknown battlegrounds uses LPV as far as I know…so they get real-time GI from sun only. Also…the LPV occludes the skylight in Interiors, which is why they are dark. Try those!

Otherwise you will have a hard time since what you want is not really doable without dynamic GI. Unity is actually slightly better suited for this since they have Enlighten…but that’s a totally different beast to tackle^^

That’s good, yes I forgot about unbound. It reminds me of Red Editor, where in Red Faction Engine we just had to drag in a Light Object and resize the sphere it to affect how much area of ambient light color to put into it. and just change the color and intensity, ect.

Only thing was you had to put quite a few of these light ambients spheres in the map to get decent lighting and to keep the map
areas lighted.

Can Unreal Engine also do cloud Nebulas that you can fly your ship through like in Freelancer?

I’ve achieved something I like using the forward render without the auto exposure…


Okay first of all thanks for putting together a video explaination. I couldn’t catch some free time to really sit down and try to understand this yesterday but today i did. So basically what you’re saying is this: Light elements such as point lights or spotlights can be used to fake the ambient fill, so basically fake the bouncing of light that comes from the source? I mean i can see how it’s a good solution but it seems like a solution that’s better for bake lighting… Can it really work with dynamic lighting (day night cycles) ? Example at night these ambient lights would still shine while the source is not even there anymore. In unity 5, honestly i at least had light bounce from source just fine. While other things are nicer in unreal when it comes to visuals, lighting seems to not be a cup of tea for my particular project in this case, as @Daedalus51 said. I guess i could control these illusion light elements through a script based on what time of day it is, but wouldn’t that be too much of a hassle and/or performance heavy?
Other than that I have to say i’m kind of disappointed with unreal’s lighting… No proper light bounce at all… Like look at this:
Moveable directional light + station skylight

So I don’t know what to do at this point.

@Daedalus51 I’ll check out what LPV is, thanks.