BP sky sphere doesn't contribute to scene's lighting :(

Development Rendering
1

I used FPS BP template and I am trying to clean it up to be as simple as possible (for a mobile platform). BP Sky Sphere was crazy complex, so I deleted it and created a very basic one following this tutorial: Unreal Engine 4 Tutorial: Space Skybox Creation - YouTube

However, while I did get simple sky sphere, I can’t get it to contribute to scene’s lighting like original Epic’s sky sphere did :confused:

If I use SLS Capture Scene for skylight, I get this: http://s7.postimg.org/kcktdq63t/skysphere_noindirect_lighting.png no indirect lighting at all, or rather, it’s grayscale, which isn’t the color of the sky sphere.

If I use SLS Specified Cubemap, I get this: http://s7.postimg.org/u8lwddbvt/skysphere_indirect_lighting.png which is what I excepted with SLS Capture Scene.

Any idea what I am doing wrong ? Thanks.

2

Make sure your custom sky sphere is larger than the “Sky Distance Threshold” in your skylight or it won’t be picked up.

Also: are you using a Quake background in the Unreal engine, you blasphemer :wink:

3

Should I alternatively make Sky distance threshold smaller than the sky sphere ? (I have it at 15k units currently)

It’s just easier for me to test lighting and stuff in UE4 with actual level model, without building one from scratch :slight_smile: Technically it’s half of stereo VR pano I rendered from Arcane Dimensions mod https://drive.google.com/drive/folders/0BwE6dxM0O2PsWUdtTmNxdXQzaUU :slight_smile: I wish I could set up stereo sky sphere in UE4 (one per eye). Any ideas if it’s possible ?

4

That should have the same results indeed. You probably want it pretty far anyway for VR, to prevent it from feeling like a cramped volume.

Wouldn’t a stereo sky sphere fail as soon as you turn your head as the individual orientation of the eyes varies from the orientation you baked the panorama from? Regardless I haven’t done much VR stuff yet, so I can’t immediately say how to achieve that.

5

I just wonder if the size of the sky sphere would affect performance in VR (draw distance should not be too far, or at least that’s my understanding of it)

You can try viewing those if you have Gear VR or Rift or even Cardboard. If you just look around like a normal person would, and not look for a way to break stereo effect (by tilting your head left or right), the stereo effect won’t break. Even if you tilt your head and not focus on “let me see if stereo effect on skybox is broken” (by simply playing the game), you won’t notice breakage.

6

Ok, so I decreased threshold and I got SLS Capture scene contributing to lighting in my modified FPS template with those gray blocks.

However, I still get problems with my static mesh map: ss2 dev stream - YouTube (some polygons are almost pitch black no matter what I do)

I am not sure what it could be :frowning: Starting to think maybe UV1 (lightmap) issues, since UE4 autogenerated it. Any ideas?

Thanks

7

Yep, seems like it was UV1 issue. I created second UV map in Blender, and on import into UE4 I checked off option that tells UE4 to generate lightmaps UV. Seems like it’s all good now.

8

Something was not set up correctly as a skysphere would normally be unlit and not need lightmap UVs at all.

This might not be relevant in your case, but another thing that might cause this is forgetting to disable shadow casting on the skysphere itself.

9

Nah, sky sphere was untouched since I created it. What you see in that video is a model of the map, which is exactly the same thing as in the cubemap :slight_smile:

I am certain the issue was with UE4 improperly generating second UV map for lightmaps. That’s the only different between previous attempt and the last one.