How we plan to make lightmaps in UE4

[ICO_hr]

@Brian Karis;126907

Are there specific ones you want? Many of the settings folks have posted as the high quality set don’t really have an impact. If all you are looking for is to dial it to 11 we can add that.

I’m not sure what most of the settings are doing but i think if make any sence at all, some of the important that can give us better results can be exposed in the editor.I understand you dont want to clutter the interface but this is going to be helpfull for some people who are not scared of waiting and burning their CPU’s for better lightmaps.

[anonymous_user_389e656c]

The auto lightmap UV code I wrote only lays out some existing UVs. If the existing UVs don’t align with edges (they mostly will) you can modify the input UVs to help it. Right now the only option is to use UV channel 0 as input. There is no need for that restriction. I’m going to allow you to specify the input and output UV channel meaning if you want to make a tweak to existing UVs to input to the auto UV layout code which does the rest of the work you can. So for example, you have your normal texture UVs in channel 0. You want to make some tweak to those UVs to use as input for lightmap UVs, do that and put them in UV 1. Then during import say that auto lightmap UV source channel is 1 and destination channel is 1. It will then uniquely lay out your tweaked UVs and use them for lightmaps.

Good! This should give us all the flexibility we need. Do you see in the future some development that could release this need of having only straight edges on the lightmaps’ UVs? e.g. straighten them in the re-layout of the existing UVs or adding more resolution to the lightmaps automatically close to the edges that need it?

In any case your work and all the improvements in the lightmaps field are greatly appreciated and are very good news!!

[jonimake]

The mesh intersection/border lightmap texel smoothing would be a god-sent. I’ve been drooling over that tech since I read that very same PDF months ago. Nice to hear it’s on the backlog

[BrianKaris]

@devel.bmad;128209

adding more resolution to the lightmaps automatically close to the edges that need it?

Nothing planned but definitely on the radar. This was a great talk on that subject http://schedule2013.gdconf.com/session-id/822381

[Ulrezaj]

Thanks for the update! The pain of lightmap UVs has been driving me consider fully dynamic lighting solutions, but the enhancement you talked about are definitely a great step towards that becoming a nonissue.

[The_Distiller]

news Brian, can’t wait to see the new method in action!

[Jambax]

As cool as this is, I’d like to see Lightmass itself get some love. There’s a lot of issues with it right now that lightmaps have no part of, like creating seams because of the way Multi-Threading is done etc. Things like that should IMO be higher priority, as all this stuff listed seems possible if artists make the effort.

[DerCrow]

I’m excited to see where this goes!

Coming from Unity, I have greatly missed the “Generate Lightmap UVs” option that Unity’s importer has. It produced some pretty solid results.

[anonymous_user_f2b8b290]

Is there any chance if maybe we can get in World Setting under Lightmass something like Advanced tab which expose some of the parameters from BaseLightmass.ini that can be tweaked and maybe to apply only for Production settings?Personally i dont have problem editing .ini files but is way more convenient if we have this in the editor.

I think what you want is already there - IndirectLightingQuality and IndirectLightingSmoothness. You can jack up the quality a huge amount (if you don’t care about build time) and it will pretty much get rid of any solver artifacts like splotchiness. Texture based artifacts are not affected.

Btw is there a limit to how far the secondary bounces travel?I’m asking because i’ve tried this tehnique with the reflectors from the ArchViz thread but using one really big plane that is lit by spot light but after the bake it didnt have any effect on my scene which i guess have something to do with the range of the bounce light affecting the world, if there is such thing like range of course.

There is a maximum transfer distance, it’s typically the diameter of the bounding sphere of the importance volume.

[anonymous_user_0051caf4]

Hi DanielW,
In general, how do you think lightmass compares with Beast - integrated into Unity engine. I have alot of experience with Beast and I’m moving to Unreal now. Any thoughts are appreciated.

[bigzer]

This is absolute great news thank you, we have tons of meshes in each level and the secondary UV requirement is eating artists work time.

I also I agree with TheJamsh, its time to solve the neighboring mesh color tone difference, this issue is making many areas of all our maps look like chessboards.
I am surprised to still see this huge elephant in the room after so many months, pretty much everyone is affected and its ruining the hard work done on the render engine to achieve eye candy results.

Personally I would not mind having a ‘final build’ option for slow but proper bakes.

Finally thank you for sharing this kind of info, not only its reassuring and allows us to tell what our problems or our priorities are but its also very helpful, for instance starting monday our artists will stop spending time on secondary UVs, one of them just happens to be doing hundreds of them from a list, I think he’s going to love you for that ^^.

[Ixiguis]

Ohhh my, great news Brian!!

I totally agree with you that unwrapping UVs for lightmaps are a pain and very time consuming, furthermore results aren’t always good unless you dedicate a lot of time for them.

I am eager to see this whole process fully automated! It’ll be a huge workflow improvement.

[HavocX]

@bigzer;129769

Personally I would not mind having a ‘final build’ option for slow but proper bakes.

I second this!

[anonymous_user_f2b8b290]

In general, how do you think lightmass compares with Beast - integrated into Unity engine.

The last time i used Beast was so long ago…it’s not really relevant experience anymore. They are using Geomerics Enlighten now. Honestly I have barely used it, just due to lack of time. I would love to see the results if someone did a comparison in quality and performance. It’s not apples to apples because AFAIK Enlighten supports dynamic light updates (but not geometry updates) while Lightmass GI is fully static.

I also I agree with TheJamsh, its time to solve the neighboring mesh color tone difference, this issue is making many areas of all our maps look like chessboards.

It’s on our minds, hopefully we can address it soon.

Thanks for the feedback guys

[VoxyGon]

You guys are

[lmetreveli]

I spent whole week making second set of UVs on meshes and time to time I was dreaming about solution - import mesh and never think about lightmaps, second UVs and etc etc. Then I saw this thread and almost cried

Shell we see some new features in 4.5 ?

[KVogler]

Hi,

Hmm, I must definitely be doing something wrong…
When I add a second, non overlapping, set of UV coordinates for static lighting, it takes me in most cases about 10 seconds.
I once had a case where I had to spend 15 seconds and one where it even took almost half a minute.

Im honestly puzzled about the difficulty the people have with it…
Just out of curiousity, could someone share a model with me that is “difficult” in terms of lightmap UVs?
Maybe the models Im using are too trivial for unwrapping becoming a serious issue…

Cheers,

[anonymous_user_138c2332]

@KVogler;136028

Im honestly puzzled about the difficulty the people have with it…

Yeah it’s puzzling why EPIC is spending precious time for not important things like this when there are other important features missing.

[Ixiguis]

In my next project (archviz), I might have to import thousands (3-4k) of models. Can you imagine the pain of having to click on each one and unwrap UVs for lightmaps? That’s simply unfeasible. (and no I can’t merge them, need them as separate objects, as they are in the source file)

Not only that, but as the source model changes, I’ll have to reimport it to UE4 (and recreate lightmaps).

So it’s not a matter of unwrapping UVs when you import a few models each day, but when you have to import hundreds or thousands per day.

Plus, I am hoping Epic’s unwrapper will yield better results than 3d studio’s Flatten Mapping (which is what I use currently).

So at least for me this feature is extremely important. And for newcomers too, the forums and answerhub are full of questions about “weird shadows on my model after build”.

[lmetreveli]

@KVogler;136028

Hi,

Hmm, I must definitely be doing something wrong…
When I add a second, non overlapping, set of UV coordinates for static lighting, it takes me in most cases about 10 seconds.
I once had a case where I had to spend 15 seconds and one where it even took almost half a minute.

Im honestly puzzled about the difficulty the people have with it…
Just out of curiousity, could someone share a model with me that is “difficult” in terms of lightmap UVs?
Maybe the models Im using are too trivial for unwrapping becoming a serious issue…

Cheers,

Time consuming. For perfect shadowing shells on second UV should be evenly spaced. So, yes, it would be great if I spend more time on modelling than on spacing shells :3