External Light Bake Workflow?

Hi guys, I would like to get some “light” in a different workflow that an artist called Alexander recently posted in his video “Unreal Engine 4 archviz - second test with simple post breakdown”. Here is the link: Unreal Engine 4 archviz - second test with simple post breakdown on Vimeo

He states that he bakes the lightmaps using Blender with cycles, avoiding to calcule lightmass lighting in UE4.
Since I don’t know anything involving Blender (Maya User), and just a little about lighting in UE4 (still learning), could please anyone clarify this new method?

Some questions that run around my brain are:

  • Do you need to create the same identical light in both scenes to match the shadows baked in the textures?
  • If so, can you export the blender light in any way, or you just replicate manually the light parameters?
  • Once in UE4, should you deactivate shadow casting in your lights to avoid duplicate them? (since I suppose you have them yet baked in your textures)


PD: Apologies for any english written language incongruence, spanish guy here :wink:

The guy said the directional light was from unreal…and since he doesn’t use lightmass…it must be dynamic. So, I think only his G.I is baked in blender, and then he import the scene in ue4, put a directionnal light where he wants. It’s probably better to match blender’s light position tho. Overall it doesn’t looks very realistic imo. But maybe it’s because of the scene and not the technique.

Lightmass is nice and all, but it would be great if there was an easy way to import lightmaps from another render. There are great GPU based renders that can achieve better lighting than lightmass and also faster…

I think Octane Render 3 will be able to do it. They have a ue4 plugin coming later this year but we don’t know much atm. But Otoy said it at GTC 2015…it’s meant to replace lightmass…it must mean something lol! We’ll see!