Large Open World Environments, Lighting, Shadowing, and VR

Once 4.8 is released, I have plans to create a fairly big environment. Included in this is a day/night cycle. I know that you can do a day/night cycle using static lighting and lightmaps, however, I do not exactly have a render farm to build the lighting, and the lightmaps would be way to big IMO. So, my other option is to use dynamic lighting, however, the overhead on this from what I have been hearing about is pretty bad. Is there a “best of both worlds” in regards to outdoor lighting?

One last thing, if OVR releases an updated SDK before 4.8 is released, would that updated SDK be included in 4.8, or would it be the current SDK version? I ask this due to my prediction that SDK rollouts are going to be growing in the next few months, and I suspect we will see an SDK 1.0 in the Fall/Winter time frame.

SaviorNT, some people have done testing with lighting for VR, My understanding is that with a moveable directional light for a day/night cycle, building lighting is quick as there isn’t any static shadows. But don’t count me on that, but I am wondering the same as I want to add a day/night cycle with my VR game.

That is the entire thing. Since the scene is has dynamic lighting and shadowing, it gives a significant decrease in performance. However, while lightmaps give an increase in performance, they also take up space on the user’s HDD (and the lightmap must be loaded into memory when called), for large scenes… I’m curious as to the tradeoffs.

I’m thinking that on smaller objects, use either no shadows, or create a “false shadow” as Epic described one of their talks; basically using a 2D plane that is Z-clamped to the environment. This is most definitely not realistic, but the performance using this method seems to be pretty good. On larger objects, shadows would need to be dynamic.

As the saying goes, discovery requires experimentation. 4.8 needs to be released ASAP.

I was running into issues trying to build lightmass for large terrain and lots of foliage…its just not doable. swtiching to dynamic lighting made everything work great…no more build times! plus if youre using a lot of grass and foliage, it looks way way better.

I’ve used a dynamic light on a large (5kmx5km) terrain and the performance was pretty good. If you want to do TOD then the amount of lightmap baking you can do is sort of limited anyway because it will be outdated once you move the sunlamp.

Modern “seamless open world” games such as Bloodborne use only a directional light and a skylight. If you look at some interiors there aren’t any shadows at all, on anything.

SavoirNT, there is a way to do a day/night cycle that may help with performance. From a quick look, some are using matinee to make the day/night cycle. here is the tutorial