Exterior Light Studies

@rabellogp can you post grass shader!
and if u are not using DFAO or DFGI then are you baking the whole scene!

Hey man, incredible outdoor scene - you’ve achieved what many of us have, and still spend countless hours trying to reach.

If you could share any more info regarding the creation of this masterpiece, it would be hugely appreciated! For example what lightmass settings did you use? and what lightmass density? could you go through your grass mesh & shader setup? Please sell these assets or a tutorial!

Thanks, man.

I’m planing to release tutorials about exteriors in UE4 for months… I haven’t managed to finish anything yet cause I’m waaay overworked with other projects. But I’ll get there [eventually :D]. Selling assets on marketplace has lower priority in my list. I think that nice tutorials are the best way to contribute with the community.

About the lightmass settings… I couldn’t care less about that on my exterior scenes:D. I mean 99% of my foliage is movable. Only the buildings and the asphalt are baked. I usually place a Lightmass Importance Volume around the main building in the scene, set lightmass quality to 3, scale to 0.7, 9 bounces and hit “Build Light” on medium or high settings. That’s it.

The “secret” to get a good looking exterior with daylight setup is to find the balance between shadows and light. A rough rule is “the more contrast the better”. AO has great importance when dealing with dynamic foliage as well. I usually plug a scalar parameter on AO input of my foliage master material. Then I tweak each material instance manually for each kind of tree/grass in the scene trying to achieve even shadow/light ratio. If you don’t do that, some plants will probably look “brighter” than others under shadows.

If you use SpeedTree to create your foliage as I do, you can also bake AO into vertex color and use that to give more depth to dynamic foliage in UE4. Another great tip is to use that same AO baked into vertex color as a mask to reduce specular in the inner/denser parts of the trees. 0.5 (default) specular should be physically correct in UE4, but for some reason it won’t look right on some dynamic foliage.

My default grass asset is a “3-materials” “plane-cluster” created in SpeedTree. The first material (~60% of the planes) is for the green grass. The second ( ~30%) is for dry grass. The third (10%) for miscellaneous stuff (broken twigs, herbs, clovers, etc). In UE4 I have a master material with a parameter (+ some nodes) plugged into World Position Offset so I can control grass height (same way Epic did in Kite Demo grass). The secret for grass is to add variation… You can be creative on that. Combine slight different grass assets in the Foliage Tool, use masks to slight change color of different regions, etc.

A last nice tip is to pay attention on your sky material brightness and overall foliage color. It’s easy to get it brighter or darker than it should be without real references… Get some real pictures of similar landscapes of what you’re trying to achieve and match sky/foliage brightness to that.

I hope those will help you somehow until I finish the tutorials. Good luck! :wink:

Alright. I shat. Beautiful work! Love it. Can you list the programs you used. Thank you.

never done a exterior scene for the lack of knowledge in how to get beautiful grass or tress.

His first post links to the various threads where he describes his techniques. Read them all - they’re a goldmine.

This looks really awesome, it doesn’t need any kind of changes

Great work. Thanks for sharing! +1 for tutorials!

For your skylight setup and the EXR sphere, what is the skylight setup?

Distance threshold?
Indirect lighting intensity?
SLS capture scene?

“Distance threshold?”
Any value larger than your sky sphere’s size (if you want to grab color of it)

“Indirect lighting intensity?”

  1. But sometimes I experiment with a bit higher value if I’m not getting enough bouncing in the interiors. Never went higher than 2.

“SLS capture scene?”
Yes otherwise you won’t be grabbing color from the EXR sphere

Thanks! Your work looks great, the foliage is very impressive.

hi @rabellogp :slight_smile:
i’m actually working on FPS

i have a GTX 1080 and my FPS are really less than yours (mine are like 20fps for an exterior scene)

  • how many triangles have your trees and grass in the LODS?
  • do you make LODs by yourself or do u use the UE4 smallprop?
  • do you use 2D trees/grass for the really far meshes?

Hi @coach

"how many triangles have your trees and grass in the LODS?"

It depends on the asset. The most important trees (the ones near the house) can have up to 200k tris on LOD0. The ones that are always kinda far from the player (inside forests and at the horizon) are simpler models that won’t have more than 50k on LOD0. All of them have something around 10k on the last geometrical LOD. The final LOD is a billboard for every tree.

All my grass is 2D. Denser clusters on LOD0 and less dense on LOD2. I put a lot of effort on trying to match the grass assets color with the actual ground texture so at the distance you won’t notice when the culling happens. That involves taking shadow into account because if your grass casts shadow it will be overall darker and at some distance it won’t match a ground color that was tweaked to match fully lit grass.

Also I try to minimize overdrawing as much as possible on all my foliage assets.

"do you make LODs by yourself or do u use the UE4 smallprop?"

I create all my foliage in SpeedTree and I use their LOD system to generate my LODs. It’s very convenient. For the non-foliage assets I use UE4 mesh optimization feature.

"do you use 2D trees/grass for the really far meshes?"

I use the billboards generated in SpeedTree for the far trees. I don’t use billboards for grass.

many thanks! i will try your tips!
man you are absolutly the best again thanks really

Hi i used same methode to make a sky the result its dark as show below please can you solve it

yor are awesome man, can you make a video on exterior video rendering?