Lets make Lightmass EPIC (and understandable)

[anonymous_user_35ba064a]

@;406660

No, of course not. The paper linked is for rendering engineers like myself who implement GI solvers. I will test out the scene monday-ish with the original settings and Rafa’s settings and see what I can find.

I for one am pretty bloody stoked to learn about your findings!
Loving this thread btw, will post my own findings soon.

[Enter_Reality]

Well, sells lots of scenes on his website, so there is no secret about that…also he made a tutorial on UE4 Architectural scene setup on Evermotion and also gives some advices around…also che Realistic rendering scene which comes with UE4 is a very good starting point…and the scene made by koola available on the marketplace…

There is no “Universal Lightmass solution” for every scene, otherwise there will be one parameter to set.

[juraj_talcik]

While working on the competition ( ), I experienced certain unpredictability of result depending on position of Lightmass Volume. The position seems obvious, it should encompass the scene. But how much ? By atleast 1 or 10perc. ? Seemingly miniscule movements of the volume, seemed to often drastically alter the splotchiness. It was so random I later didn’t touch it even if needed. I got the best result with the very smalled encompass I could get.

I also sort of don’t believe universal settings for perfection can be found with photons as secondary GI solver. MentalRay tried for years and it is what it is when it comes to complicated GI (of architectural spaces), requiring very unique treatment depending on scene. Which is also why other renderers brought more advanced secondary solvers (for example Vray’s LightCache, while also not perfect esp. when it comes to lightleaks, it’s far more evolved than photon mapping, and also has mode to work in world space and is often used for baking down scenes).

[mihanix]

My experiments:

Scene: MEGA

File BaseLightmass.ini: MEGA

change settings:

DirectPhotonDensity=100000000

And parameters koola:

[DevOptions.StaticLightingProductionQuality]
NumShadowRaysScale=32
NumPenumbraShadowRaysScale=64
ApproximateHighResTexelsPerMaxTransitionDistanceScale=9
MinDistanceFieldUpsampleFactor=7
NumHemisphereSamplesScale=64
NumImportanceSearchPhotonsScale=6
NumDirectPhotonsScale=32
; Decrease direct photon search distance so that we will have more accurate shadow transitions. This requires a higher density of direct photons.
DirectPhotonSearchDistanceScale=.5
NumIndirectPhotonPathsScale=32
; Need a lot of indirect photons since we have increased the number of first bounce photons to use for final gathering with NumImportanceSearchPhotonsScale
NumIndirectPhotonsScale=64
NumIndirectIrradiancePhotonsScale=32
; Decreasing the record radius results in more records, which increases quality
RecordRadiusScaleScale=.45
InterpolationMaxAngleScale=.75
IrradianceCacheSmoothFactor=.75
NumAdaptiveRefinementLevels=3
AdaptiveBrightnessThresholdScale=.25
AdaptiveFirstBouncePhotonConeAngleScale=2.5

Render time: 4 hours
On machine with i7 950 3.07 GHz RAM 24 Gb

I’m afraid to imagine what will happen to the big apartment!!!

I do not understand these parameters. Just do not have time to study the photon mapping. He began to study and my head was going to explode soon. It is a science. Examples would be the settings for daytime sunlight, cloudy, evening. Why not make the presets. How well do creative work, not to study the photon map. I really liked the graphics in Unreal Engin 4, but once started architectural visualization, faced with the mysterious file BaseLightmass.ini

[Enter_Reality]

@palak123;406807

I think you have missed the whole reason behind this thread. Its not targeting for specific values, but to understand Lightmass as whole.

As koola himself admitted that he has no idea of the setting he changed in baselightmass.ini, so using his values without knowing what they are doing exactly is of no use.

rafaries tutorial on evermotion is not even scratching the surface of lightmass, leave the usefulness of it. One of my friend had bought a scene(Rivera house) from his site and luckily I got a chance to have a look over it and I found that there was no baselightmass.ini provided with the scene but, I am yet to rebuild his scene and I extremely doubt that the scene quality will be the same as provided.

I can’t believe that koola is the only one in the entire comunity which spent 1-2 days messing around with the baselightmass.ini settings…and as seen even if he didn’t understand everything the results speak for themself.

Regarding each single parameter on the .ini file, well if DanieW is willing to share some knowledge would be great.

[koola]

I did some quick tests too.

(to speed up the testing I use lowres lightmaps)

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”.

And stop using my old BaseLightmass.ini, like I already say, it’s roughtly just random values^^.
You don’t need to boost all the values if you just light your scene with a skylight.

With the spot/reflector technique (that simulate a skylight with more than 2 bounces) you need more tweaks (and more render time) to have a good quality.

[Robbie222 (Roberto Filip)]

Great finding Koola!

[anonymous_user_6096f04f]

Thanks for the info Koola. I would like to hear chime in on this before we all take it as the gospel.

"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”.

[Raghu]

@koola;406830

I did some quick tests too.

(to speed up the testing I use lowres lightmaps)

https://hkgame.files.wordpress.com/2015/10/testsky_0000_layer-31.jpg

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”.

https://hkgame.files.wordpress.com/2015/10/testsky_0002_layer-1.jpg

https://hkgame.files.wordpress.com/2015/10/testsky_0001_layer-2.jpg

And stop using my old BaseLightmass.ini, like I already say, it’s roughtly just random values^^.
You don’t need to boost all the values if you just light your scene with a skylight.

With the spot/reflector technique (that simulate a skylight with more than 2 bounces) you need more tweaks (and more render time) to have a good quality.

@Koola - What a perfect timing, Now we got all the fuel we required to boost Lightmass learning. If possible kindly have a look on the level with spot lights for the light leak errors.

I have to confess that I am already using NumHemisphereSamplesScale=64 Value on all of my latest projects without touching other values much (I found this during my experiments that this value is greatly improving the results). But again all I know was this value is improving my results but how? and why? are the questions which still need answers. Light leaks are still unresolved on .1 Value in Static Lighting Level Scale.

@ - I am becoming desperate to know your findings. My hopes are super high. Kindly provide explanation behind all this.

Looking Forward.

[heartlessphil]

*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*

Is this even possible to use those in a real scene and without a huge renderfarm tho? :-S

[meijervis]

@;406875

*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*

Is this even possible to use those in a real scene and without a huge renderfarm tho? :-S

Im wondering about this as well, especially cranking up the Indirect Lighting Quality adds sooo much render time.
And I actually found that a value of 2-3 gives me a much cleaner result than anything over that.

[heartlessphil]

@sandermer;406917

Im wondering about this as well, especially cranking up the Indirect Lighting Quality adds sooo much render time.
And I actually found that a value of 2-3 gives me a much cleaner result than anything over that.

I’ve done scenes with .9, 100, 10, .66 and it took round 7 hours on 2 machines. Not too bad! Under 10 hours is ok-ish but over 10 hours it’s a bit long. Koola might use a bigger renderfarm who knows!

[heartlessphil]

Most people serious about arch-viz probably have access to a decent render-farm. Even if it takes 10 hours for the final bake, this isn’t a big problem as long as it’s predictable in the end!

[anonymous_user_6096f04f]

:

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

[3DStephen1 (3DStephen)]

@;407391

:

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!

[Icchansan]

There you go!

[/QUOTE]

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

Thanks for sharing you guys.

[Morderkainer]

@koola;406830

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.

[anonymous_user_6096f04f]

There you go!

[/QUOTE]

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]

@ikifenix;407589

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.