This is going to be huge. At the moment the painstaking task of manual lightmaps is a real setback for massive architectural projects and models due to just how long it takes. Especially since automatic unwrapping or flattening for lightmaps generally doesn’t work.
Is there an expected ETA on 4.5?
Cool. Thank you. Maybe its a dumb question, but will I be able to do so for existing meshes, like a button to generate a light-map inside the mesh editor.
Yes. Just change the property in the mesh’s build settings.
@Brian_Karis
Any ETA on 4.5?
Just popping in to say great work, thanks for taking the time to make our lives easier.
Thanks a lot.
Can’t wait for this!
Any ETA for 4.5?
Hey, did any of this get implemented into 4.5? I didn’t see anything in the latest documentation…
They did. You’ll see an option in import dialogue window to generate UV’s. You can also do that later on from static mesh editor Details panel, and it will create a second UV channel with no overlapping faces automatically.
I know this is not a place to post crash, but a heads up. The editor crushed when I try to create lightmap using lightmap source 1 (as oppose to 0).
Also, I notice (I made like 20 lightmaps in UE4 so far from my existing meshes), that what the UE4 does is just to blown up UV in the space. Is that whats it actually does. Not saying its not useful, its useful for meshes that share texture, if I use the channel 0 original UV as lightmap, I am wasting UV space, with the UV expand to cover full UV space (1,1), I get better lightmass using lower resolution.
Though, I was expecting UE4 to completely reasign UVs for optimum lightmap.
Hi Starseeker,
This has already been submitted as a bug report (TTP:348930) for the crash a couple of weeks ago.
There are still improvements being made with the auto-generated LMs.
If you have a specific need to have your LMs set up a certain way it’s probably best to manually create those. It’s good to remember that the LM is being generated based off the UV islands of the texture UV. So the layout will be organized based on those UV islands.
In regards to having a UV 1 when not needed. You will still be using a lightmap UV, but instead of it having a dedicated UV that is setup differently you it will use the Texture UV as the LM UV.
Thanks for the swift reply !
Ok, gonna try it today. Thx for the clarification. 
ps. Tested it, new Lightmap works really well. It let you do the lightmap on multiple LODs too. I was going to report that there were bugs in 4.4 that prevent you from using lightmap with LODs, but i guess this solve the whole issue.
Question, there’s this differeent min Lightmap resolutions in all LODs tab but there’s also actual Lightmap Resolution in Lightmap tab.
How exactly do these values work?
So, what’s the consensus? Is everyone still doing manual UV mapping for the lightmap or using the auto generation? I’ve found that doing it manually produces good results (by ensuring that the UV shells are spaced appropriately and snapped to the grid) but it is rather time consuming to UV map every mesh twice.
If UV auto unwrapping method could get any close to legendary Unfold3D’s algorithm this would be heaven.
My results with Unfold3D have been far from desirable, perhaps I’m doing it incorrectly. As a result, I’m still manually planar mapping, scaling, and stitching everything. Very time consuming.