Hello
My case is a 16K*x16K world, with a sun in directional movable light (sun + 360 rotation). This is done.
But my shadows are too dark. I read about GI in UE4. but it seems to be deprecated.
How to get similar result with lightmass and movable dynamic directional light. How Make interior of houses not completly dark without putting lights inside to simulate the sun coming through windows. Or the short answer is UE4 cannot make a game like Skyrim/GTA V/Watch Dogs. How Fable Legends are doing this? The tecnology of fable legends will be avaliable to subscribers? Or a realy missing something?
The resume of question is: “How to get indirect lighting actualiy on version 4.2, using day/night Cycle”
To use GI in UE4 you should disable Lightmass.
Find your ConsoleVariables.ini file, under the uncommented [Startup] section add this:
r.LightPropagationVolume=1
Open editor and Lionhead’s GI solution will be loaded.
To disable Lighmass; In Editor’s main window go to Edit > Project Settings…
Under Engine > Rendering section find the Lighting field and disable " Allow Static Lighting ".
UE may ask you to rebuild lighting and next time it runs the rebuild process, Lightmass will be disabled.
Add a PostProcessVolume to your scene and on its fields you should see a " Light Propagation Volume " section, adjust its settings at will. Done.
But this is not deprecated?
Nope, Lionhead is using it. I am using it, lots of devs are using it on 4.2.
And how to solve the leaking lights
?
This is not light ‘leaking’. To adjust shadow bias you can try to minimize this problem adjusting LPV’s “Light Injection Bias” and on your ‘sun’ (directional light) you can adjust “Shadow Bias” and “Self Shadowing Accuracy” to a point where the distance of shadow to its caster will fit the correct casting point for your map objects. Not perfect neither automatic, but I think this is way better than wasting time rebuilding static lights 
Well, I would take a look at CryEngine then. Because this IS Lionhead’s system, and we won’t get anything better in UE4 for a while.
If you design your assets with the current system’s limitations in mind (like Lionhead does) and adjust settings properly, you can pretty much get rid of the artifacts you have in your scene.
