Lets make Lightmass EPIC (and understandable)

[StephaBon]

Daniel:

Is it possible to give us something like this? In Modo for example if there is noise I know to increase the samples in the lights. So, for us non technical people can we get an over view like.
Blotchy try x, x and x
Light leaks, increase lightmap rez and x
Etc.

All this tech talk makes my head spin. Hahahaha

There you go!
https://wiki.unrealengine.com/Lighti...eshootingGuide

[Icchansan]

There you go!
https://wiki.unrealengine.com/Lighti...eshootingGuide

Oh! I'm going to check those at home, getting lots of weird issues in my level.

Thanks for sharing you guys.

[ikifenix]

I use this values in editor parameters :

Static Lighting Level Scale : 0.1
Num Indirect Lighting Bounces : 100
Indirect Lighting Quality : 10
Indirect Lighting Smoothness : 1

And in the BaseLightmass.ini :

NumHemisphereSamplesScale=100

In my tests, this is the only parameter you need to tweak in baselightmass.ini to remove the skylight "splotches".

You are my hero, I wasted 2 days searching for a solution.

[RI3DVIZ]

There you go!
https://wiki.unrealengine.com/Lighti...eshootingGuide

Cool, that helps thanks.

[serriffe]

alright! I've been waiting this for type of thread- now that we got the heavy hitters in the line up makes it even better. I will post my results as well.

[koola]

You are my hero, I wasted 2 days searching for a solution.

Again, I don't know what I'm doing
There is certainly a better and faster solution.

[heartlessphil]

You are my hero, I wasted 2 days searching for a solution.

I hope you have 56 000 cpu cores available or brace yourself!

[ikifenix]

Again, I don't know what I'm doing
There is certainly a better and faster solution.

I hope you have 56 000 cpu cores available or brace yourself!

Lol, for my scene I don't need super quality, just don't be full of splotches everywhere.

Screenshot of my scene before ini change:


Screenshot of my scene after:


Build lights 4 hours in a AMD fx6300.

Static Lighting Level Scale : 0.7
Num Indirect Lighting Bounces : 100
Indirect Lighting Quality : 10
Indirect Lighting Smoothness : 0.7
And in the BaseLightmass.ini :
NumHemisphereSamplesScale=100

I haven't more screenshot of before vs after, but had splotches like that everywhere, and now is a lot more clean, for me, this balance time vs quality is ok, I know isn't perfect, but good enough:

[RI3DVIZ]

I have a question. If the original value was 8 in the .ini for NumHemisphereSamplesScale why the jump to 100? Did you guys try 16, 32, 64 etc. first?

[Enter Reality]

I notice that, for really nice "contact shadows" see Raghu post for reference, check the second picture the indirect lighting smoothness needs to be around 0.4-0.7, it really depends on the scene ( I'm using bounce cards ), since that value can mess up the entire scene.

Do you use any alternative tricks to achieve those soft shadows?

[3darchstuffs]

Hi all here are my experiments.

The level with spot lights

Rendering time 2:45 Hr

On I7 2600 with 8 GB ram.

lightmass resolution of all the wall were 256 and roof/floor resolution were 1024 in both the scenes.

World Settings

Static lighting scale = .4
Num indirect lighting bounces = 100
Indirect lighting quality = 4 (also built the scene on 10 with all other setting remaining same and it didn't fixed the light leaks.)
Indirect lighting smoothness = .25

Changes in baselightmass.in were!!

NumShadowRays=128
NumPenumbraShadowRays=128
NumHemisphereSamplesScale=128









--------------------------------------------
The level with shadow splotches

Rendering time 26 minutes

World Settings

Static lighting scale = .1
Num indirect lighting bounces = 100
Indirect lighting quality = 4 (also built the scene on 10 with all other setting remaining same and and there was not a big difference in removal of shadow splotches.)
Indirect lighting smoothness = .25

Changes in baselightmass.in were!!

NumShadowRays=128
NumPenumbraShadowRays=128
NumHemisphereSamplesScale=128











CONCLUSION which I have came so far.

To render a large scene with more details or on live project as the same quality of contact shadows in the sample scene


Static lighting scale = .4
Num indirect lighting bounces = 100
indirect lighting quality = 4
Indirect lighting smoothness = .85

Changes in baselightmass.in were!!

NumShadowRays=128
NumPenumbraShadowRays=128
NumHemisphereSamplesScale=128

Along with all wall lightmass texture resolution to 256 not more than that and all the objects inside the scene to 128 and floor/roofs to 1024.

Still not able to remove the light leaks from spot lights. Doing further experiments to find it.

@ DanielW - Waiting for your result and full explanation of baselightmass.ini and painfully waiting to overcome these light leaks.

[feingeist88]

So, I am wondering. What is smarter. Light your scene with only a skylight and a directional light or use the bounce card + spotlight technique? Which gives better results?

[Enter Reality]

So, I am wondering. What is smarter. Light your scene with only a skylight and a directional light or use the bounce card + spotlight technique? Which gives better results?

From what I've seen if you're using only sunlight and skylight, in order to have proper indirect lighting inside an apartment for example, you should increase the Indirect light intensity on the light itself, but that for me seems to be the main problem with light leaks, so I usually stick with bounce cards.

The bounce card technique is used widely on Max/Maya/Vray/other renderer because it gives better results and you can control much better the indirect lighting on an area.
I also use a bit of boost on the lightmass settings to increase the overall brightness on the scene...but also using the post process Indirect lighting gives you good results ( in realtime, which is nice ).

[feingeist88]

Sounds good I will give it a try!

[heartlessphil]

Good findings Rafael!