Demystifying the Skylight [Unreal Engine 4 & 5]

Hi everyone, welcome back. It's great to see you again. It gets a little bit lonely in this void here.

The topic of today's video concerns the Skylight Actor. So the Skylight is one of the most powerful, but most misunderstood and misused lighting tools in the Unreal Engine.

So most of what we're talking about today has already been covered in last week's livestream right here.

But I wanted to make a dedicated video about this because I totally understand that not everyone has the time to listen to a two-hour livestream.

that being said this was less of a two hour live stream and

more of a two hour live course i was going ahead and

talking about the skylight talking about my workflow when

it comes to lighting exteriors it was a really good time and not

just because you know i was talking for two hours but you

guys the community was one of the best parts of this live stream you guys ask questions you answer your own questions as well as well as offering other tips and tricks that even I didn't even know about.

I've been using Unreal for, what, 10, 12 years now? And I'm the first to admit that I'm still learning new things every single day.

I am an eternal student, and there's so much to learn. So if you want the length of that live stream, you can find it right there. Right there.

It's hidden, but it's there. And I encourage you to either go watch it and to come join us in the next live stream. We'll be happy to have you.

So I'm fully aware that I've been talking for way too long now. You want the juicy tidbits of information. So let's get started.

All right, so now that we're in Unreal, the first thing I always do before even placing any light is to create a Chrome ball.

Okay, so we're going to go ahead and add a sphere here.

I'm going to drop it in here, and I'm going to add a Chrome material to it.

and you'll see the chrome material is very simple it's just a base color of 0.8 or can be one

one or the other having the metallic set to one and the

roughness at the zero okay so this is going to give you a perfectly reflective

surface now the reason i create a chrome ball here is because it's

going to give me a better visualization of what exactly is

being reflected in my scene okay so you're going to understand how this works real soon so bear with me now that we've created our

Chromeball here I'm going to go ahead and add in the lights panel up here I'm going

to go add the skylight now

look at the boring part out of the way one of the main thing that the skylight

is used for is for HDRI so

if you will have an HDRI that you got online and you want to use that

you apply that with the skylight so if you have

an HDRI that you found online you want to use that for your lighting

you apply it to your skylight so in order to do that you need to go into the details panel and in source type right here we're going to go click on SLS specified cube map.

Okay. So once that's done, you can choose your cube map right here.

And we're going to go just use one of these, for example, and you'll see right away we have,

we can kind of see our trees and our HDRI showing up in the reflection of our Chrome ball.

This is why the Chrome ball is so useful because it really shows you what's being lit in your scene. All right.

So now that we've covered how to use an HDRI, let's get into the fun part and why the skylight is such a powerful tool. Okay.

So I'm going to reset this right here. I'm just going to leave it to captured scene. And now it's where things get a little bit interesting.

So what I'm going to do first and foremost is I'm going to disable ray tracing because I don't want any ray trace reflections affecting my Chrome ball.

I want to make sure that the Chrome ball is only showing what the skylight is doing to it.

Okay, so I'm going to use a console command and turn off ray tracing.

And so you'll see now we've got no more ray trace reflections on our Chrome ball here.

Just we just have the sky and the big black bottom of the sphere here.

Now the first thing I like to do when using the skylight is I like to set it to movable right here.

The reason for that is if you have distance fields enabled in your project, so distance field, ambient occlusion, you're going to get much better shadowing with the movable skylight.

If you're using ray tracing, you don't need to worry about that. You're going to get proper ray traced shadows if you choose the checkbox.

Obviously if you're baking the light doesn't have another topic entirely. But for now we're going with dynamic lighting, set it to movable.

Now the skylight by default has a myriad of settings that are pretty self explanatory, like intensity scale.

You know, we can choose the brightness of our, of our skylight here.

We can choose the light color, add a tint to it like this, whatever you want. That's pretty straightforward.

I think everyone understands this effects worlds and effect world is kind of an

important one because as you probably notice, if you hide the skylight in the outliner right here,

you'll notice it's still affecting our scene. It doesn't actually hide anything.

So in order to hide the skylight, you need to disable effect world like this. Okay.

Now, the next thing I like to do is if you scroll down, notice how the bottom of the chrome ball here is totally black.