Exterior Light Studies

Hello, guys.

I’ve been playing around with my old projects trying improve exterior lighting. I never liked too much PP in my scenes, but I always use “ideal” light positions and slight high exposures and contrast to make things popup. At this time I went for a more natural and mundane look. Less contrast, less saturation, a bit of underexposure… Almost like if I was taking the raw files straight from my DSLR.

The lighting setup is basic. Sunlight (almost white, intensity 5) + skylight (intensity 1). A huge sphere with EXR texture for the sky (the skylight is capturing colors from this). Lightmass at “Medium” settings with quality 3 and scale 0.8. The building (a tweaked version of Evermotion’s Archexterior V2) and the landscape is static. All the foliage is dynamic (90% of them created by me in SpeedTree, 10% from kite demo). It takes about 30min to build.

There is no custom LUT in the PPV. I’ve increased the contrast and tweaked “Crush Shadows” and “Dynamic Range” to avoid pitch black shadows or exploded whites. Speaking of shadows, they are Cascaded Shadows (distance 6000) and Distance Field Shadows (distance 150000). I need the Distance Field Shadows here because all my foliage is dynamic and won’t cast static shadows where the Cascaded Shadows end.

I don’t care too much about performance in my projects because they are meant to be played only in my machine. With that in mind, I’m getting 35~55fps at 1080p on a GTX 980Ti. The main performance hit comes from dynamic shadows on foliage.

The grass is scattered all over the place with grass tool (foliage types associated to landscape materials). I’m not selling any of my assets by now and I don’t plan to do so. They are all made in SpeedTree and I’m not allowed to sell assets made in this software. I have some tutorials coming though. I had to pause them for a while for personal reasons but I’ll get back to it soon. Meanwhile, most of my techniques related to foliage are described in my other topics:

C&C are welcome and feel free to ask anything. :slight_smile:
This is also in my Behanceand Artstationpages in slight higher resolutions

This looks really awesome. Is there a possibility to download this testscene, or are there paid assets in it?

So nice !

I have some few questions :slight_smile:
(I’m new with UE)

You’re using a static skysphere with hdri on it. How huge is the sphere ? Do you manually set your directional light to match with the sun on your hdri ?
Can you show us how is the material for that skysphere ?

About your trees. You say that they are dynamic. Where did setup that ? In the foliage tab, Affect Dynamic Indirect ?

Next question, where do you tweak the “Crush Shadows” and “Dynamic Range” ?
The cascade shadow is on the directionnal light but I didn’t found the two others.

And my last question. I have an old i7 2600k - 16gb ram - and an old gforce GTX460. I know that my cg is too old but what do you think about the cpu. Is it enough ?

your cpu is still very good. Change your gpu :wink:

It’s half the size of BP_Sky_Sphere. A basic Sphere mesh with 15000 units of diameter.

Yes. Then I attach the directional light to the Sphere so I can rotate de sky and the Sun will keep its position relatively to the sky texture.


In the Foliage Tab when you select one or more instances you have there, you’ll see a lot of settings related to that instance. In those settings, look for “Instance Settings” group and set “Mobility” to “Movable”. Than disable “Cast Static Shadow” and enable “Affect Distance Field Lighting”. This last one is necessary for Distance Field Shadows to work.

In the Post Process Volume details tab. You need to have a Post Process Volume in your scene.


Distance Field Shadows options are right above Cascaded Shadow Maps in the directional properties:


You must activate Mesh Distance Field in your project to be able to use it though.
Edit->Project Settings->Rendering->Generate Mesh Distance Fields (you’ll need to restart the editor).

Static Shadows are default. They’ll be replaced by Distance Field Shadows as soon as you activate it.

That CPU is fine. The GPU depends on what you’re trying to do with UE4… If you are just learning and playing around with some tutorials, you should be fine. But it also depends on what you’re trying to learn. It certainly won’t handle large scenarios with lots of foliage or high res textures and lightmaps. You are the best person to tell if it’s enough really. If you’re struggling with slow viewports on your projects then it’s not enough :slight_smile:

Hi Rabellogp,

Thanks for your answers. Very Usefull.

About your hdri material, the 3 nodes Hueshift, Desaturation and Brightness are Constant node ?
Also, you use only exr files ? When I’m using an .hdr files, the TextureSampleParameter2D node has an error (Param2D>Requires Texture 2D).
Another issue I get with hdr or exr file, the sun in the file looks wierd. Did you ever have that kind of thing ?

Once again, very amazing work !

rabellogp punches with some heavy KO’s comming from his grass again. :smiley:

Great work as usuall, and keep posting - it is inspiring! Can’t wait that tutorials though. 8)

Yes, I’m using EXR files because HDR won’t work fine as a texture to place in objects (I don’t know why and don’t know if there is a way to fix that). So I convert the HDR files to EXR in Photoshop.

You are getting weird visuals because you’re trying to tweak the texture via its own parameters (like the Brightness that you changed to 0.2). Don’t do that, it won’t work fine for HDR and EXR files. Instead, use those nodes in the material like I did. They are parameters so I change them in real time until I get the results I want.

Thanks, man. :slight_smile:
I’ll do my best to finish the tutorials soon. I’ll post on all of my threads when they get ready.

I love your stuff, can’t wait for the tutorials! I actually have money set aside to start my SpeedTree subscription but I think I’ll wait till you release your tutorials so that I can get maximum benefit :smiley:

these are great! I always followed your work, keep em coming :]

i would love to see that tutorials too <3 written? videos ?

great job anyway !

Those are great ! Well done.
When it comes to quality, did you see an improvement using distance field soft shadows ?
I’ve read the very technical wiki page about the subject a number of times but I have a hard time grasping the concept.
Does it improve the quality of the image when we are not using moving lights?

written tutorials mainly because I can work on them gradually when I have some time to spare…

On the contrary. They rely on distance field meshes and those are essentially a rough approximation of the original mesh. So I consider them impracticable for any detailed object near camera. And it causes aberrations on thin objects. The best approach is to use Cascaded Shadows near the camera and Distance Field Shadows far from camera.

any estimation date for the tutorials please ?

Nothing short of amazing! Just as I feel I’m improving, you come along and do this to me :smiley: Those Ficus trees are still blowing my face off.

Keep it up. Look forward to the tutorials

I don’t want to promise anything because who knows :stuck_out_tongue: But I really hope I can finish them before July

i hope that too :slight_smile: and even before that :stuck_out_tongue:

thanks and good luck anyway !


nice work!

do you use lightmass for all of this scene or just the building?

Thanks, man. Only buildings and landscape (the landscape mesh, not the foliage scattered over it).