Lightmass: multi-bounced sky lighting

You use those settings with production high or medium quality ?


Full settings described for that scene in #260

Hey guys,

First of all I would like to thank you and congratulate you for your awesome job on pushing UE’s lightmass further.

I am facing a dilemma : the project I am working on has a deadline next week. So UE4.18 full release + substance plugin update probably won’t be in time. Is it possible to use 4.18’s Lightmass on 4.17? Or is there some trick to make substance plugin on 4.18?

Just use the bounced lighting exe in this thread for 4.17. You’re not going to get all the 4.18 improvements, but it’s better than nothing.

The livestream talked about the new lightmass features here 4.18 Preview | Feature Highlight | Unreal Engine Livestream - YouTube

sounds like doors and other moveable objects will be much better integrated.

Hi everyone
I’m on 4.18 preview and i can’t achieved what u guys have. I tried to lit my scene with only HDRI but it seems to dark. Is it normal? Or do i need to add point lights?
My setting are in attachment.
Thank you for your help

You should be able to get enough light from that giant window. It looks to me like either your materials are too dark to reflect an adequate amount of light (meaning most of the light will be lost at each bounce), or your lightmass importance volume isn’t actually surrounding the area of interest.

Or your auto-exposure settings aren’t ideal for your scene.

Yea like ZacD said, definitely an exposure issue. Try playing with the exposure bias (with an unbound post processing volume of course).

Thanks a lot guys for your help. Like ZacD said it was my auto-exposure. Save me a headache.

Yea Daniel,

Adjusting the
VisibilityTangentOffsetSampleRadiusScale from 0.8 to 0.001 and
VisibilityNormalOffsetSampleRadiusScale from 0.5 to 3
I managed to eliminated almost all the dark edges on a huge internal archviz scene.

Thanks for the hint!

welcome back Raf :slight_smile:

actually wich settings do you use on 4.17?
ini and world

Daniel and Luoshuang, you guys did a great job improving the skylight in 4.18, something we desperately needed! Would be absolutely great if you could address that dark corners issue, it’s really noticeable in certain situations. Other than that multibounce skylight is fantastic, thanks!

Hi guys. there is any connection between num indirect Lighting bounces and Num Sky Lighting Bounces? i mean when you pute Num indirect Lighting Bounces to 0 skylight multi bounces will work?
its seems when you pute num indirect Lighting bounces to 0 skylight bounces will stop to working .( i mean when skylight is your only light source )
and i want to know there is a connection between roughness object and bounces? i mean an object with specular to 1 and roughness to 0 will have more bounces light?! ( i test it and its seems roughness of objects is not effect to bounces )

Nothing special. I achieved pretty good results with hight quality preset settings :slight_smile:

Here are some tests in 4.18.
The indirect lighting spreads beautiful. The settings I have used:

Static Lighting Level Scale = 0.15
Num Indirect Lighting Bounces = 7
Num Sky Lighting Bounces = 7

It is connected to Num indirect lighting bounces in world settings.

hi man :slight_smile:

i try your settings on “lightmass” scene. i have nice result with very fast building. but i get that error in

i get that errors:

  1. typical 4.18 shadows in the corners
  2. bounces on wall far from sourse light

how can i resolve for you? wich parameter have i to change to get off that bounces on wall?

Does this still work if you un-check lower hemisphere is black. As that is supposed to give you an extra bounce am i correct?

hi all
my point lights have low resolution { 4.18 preview 4 }
how can i solve it ?

Hi guys, I have installed the UnrealLighting Mass in UE4 4.18 but it doesn’t work.
Give to me this error

Entry point not found.
What I have to do to fix it?