Hello, i just want to know purpose of skylight is itend to be used with dynamic lighting or it improves lightmass baking? I just thinked myself not using skylight and just bounce “REAL” lights like direct sun light and artificial lights inside buildind is more realistic way to approach it? am i correct or skylight is must use? or which one will give me better results? and again my goal is achieving most realistic shadow-light scenario, great build times are not a concern. thank you.
Hello alperenozgur,
Realism is achieved by a number of different systems working together. I believe what you are trying to achieve is a greater number of indirect light bounces without utilizing the sky light. A sky light is an excellent way to achieve indirect lighting and ambient fill lighting without a heavy strain on performance. Many lights inside of your building will often result in the influence of of lights overlapping each other.
To that end, as far as lights are concerned, sky lights are the way to go.
I am linking you our documentation on Lighting the Environment. In this section you can research how others have combined various techniques and practices to achieve realism. I am also linking you to our section on realistic rendering. Which shows an example that uses materials, lights, reflections, and maps to achieve different stages of lighting throughout the day.
https://docs.unrealengine./latest/INT/Engine/Rendering/LightingAndShadows/index.html
https://docs.unrealengine./latest/INT/Resources/Showcases/RealisticRendering/index.html
thank you so much. i looked at realistic lighingt link and setups at documentation are not using skylight if i understood correct; but you saying it is way to go. still litbit confused. btw after 4.11 release we will have light portals like vray and skylight will be less needed i think… or i am really not getting the point you trying to explain me. maybe i just have that prejudgement from the past experiences with cgi which is “fill lights or ambient lights are bad because they are artificial and making the scene look litbit DULL”.
Hey alperenozgur. I just wanted to put in two cents here. You are correct in that the old way of thinking of using fill lights or area lights are bad because they do not properly simulate light bounce and distance falloff. Cg programs like blender cycles engine has bounce lighting that makes fill light obsolete. Unreal engine isn’t there quite yet because it is a Physically Based Render engine. It takes light reflectance values of materials to properly simulate surfaces like the difference between rock or metal or plastic and can generate shadows cast from objects in the 3d world but we have to cheat some to achieve realistic light for now using lightmass importance volumes which precompute bounce light in the volume. Fill lights play a huge role in lighting the darkest areas slightly to simulate the distance falloff so that in an interior scene there isn’t a high contrast between areas in deep shadow and areas in direct light. The link that included is an excellent way to see how all the little pieces fit together to make good interior light. I also would say to look at the Berlin flat example project for a physical look at how interior lighting can be achieved.
Checkout these tutorials:
http://rag3dviz./tutorial/hdri-lighting-in-unreal-engine/
https://ue4arch./ue4archs-unreal-engine-4-lighting-workflow-part-1/
I’m currently trying to use a combination of skylight and directional light (the skylight component appears to be very dim in internals, though, and I’m not sure if it still uses only 2 bounces)