I have Unreal Engine 4.5, I’m having a very hard time making a high quality/production quality sky for my level. I have two separate projects which both needs a sky/cubemap. I have looked at Epic Games Unreal Engine documentation on cubemaps and its not very helpful to me. I have check on the YouTube videos on making a space sky and the compression quality is awful (there’s not a lot of tutorials on making high quality sky-boxes from scratch in Unreal Engine 4). How did Epic Games make those high quality skies in their content examples and UT4 maps (CTF-Facing Worlds is a good example)?
Very much interested in this too. It was a big topic in the subreddit as well but no conclusion. This is so important for the immersion of a game.
If you just want six textures:
You could turn off compression.
You could use one grayscale alpha texture (which may compress better) and a separate colorization texture.
You could use a custom shader that measures brightness and then calculates color, to avoid compression problems.
However, I’ve also seen artists have very good success with sky boxes that are made of geometry – separate polygons for various “objects” in the sky. This lets you use more, smaller textures for a visually higher-resolution result.
Can you provide a example? I want to make a good choice of which method is the best. I wish Epic Games showed how they made their own cubemaps from scratch. They have some really good looking ones for Unreal Tournament 4.
EDIT:
Actually after looking at CTF-FacingWorlds WIP for Unreal Tournament (UT4) materials and static meshes. I actually like the method of sky boxes that are made of geometry better than the cubemap method better. It seems that Epic Games likes that method better as well.
One thing you can try, which we have been using in 3D projects (as well as some internal UE tests) is using Vue to generate your cloud/sky environment, and then rendering that using a spherical camera for your latlong HDR.
Yes… I have a headache because of (high quality cubemap/sky) 
And the following video made me disappointed
Unreal Engine 4 Tutorial: Skybox Creation
There is topic about sky and cubemaps: [VIDEO TUTORIAL] Creating High Resolution Space Scapes - Community Content, Tools and Tutorials - Unreal Engine Forums
Yes it is about stars, nebulas etc. sky, but if you have cloudy texture that can be turned into cubemap then watch tutorial in above link.
Few thigs that work for ue4 (and are not cleared in video):
- use Ogre setting to export those star textures
- AMD tools after you exported in ogre format are best for making cubemap, else you need photoshop for rotating some face textures
And
If you have crappy and very low level resolution on your sky, it is due to distance to sky dome and fact that mip map optimization kicks in.
So change your compression (or LOD) setting in that dropdown menu in properites of cubemap texture. I think one you want is “no mipmap”
PS. same cubemap trick with mapping it to sphere uv (but reversed) works wonders for planets, it almost eliminates ugly polar regions stretching.
Very useful info! I am doing a sci-fi space theme for my unreal tournament level.
Does anyone know how to make a high resolution environment cube map texture? I want to do the sky dome method of making the sky. Is there any good resources on getting sky dome textures? Is there a way to make a high resolution (4K) sky dome texture?
See above post for night/star skydome.
Recently i had idea for cloudy sky (it can be also done for dusk/dawn scenes).
make sky plain blueish color (or just white/grey)
add to this cubemap with gradient either linear around horizon or bit of circular for spot where sun is
you can use emmisive color or just multiply by light color ets to simulate time of day and sky color
So you should have nice background gradient.
Now we need clouds:
use flat black box and vector field to generate slowly moving clouds. Then camera capture to create grey (alpha mask) texture.
Then use that texture to overlay animated clouds on skydome.
Or just make huge vector field (big voxels, not huge number of them) and animate clouds with that field.
If you want plain 4k texture for sky you need to render it in your favorite 3d app. Look for tutorials about skydomes in maya, blender, max.
When you have texture use that amd tool to create cubemap. And be warned that 1024x1024 texture is 6 textures 1k by 1k. So 4k cubemap texture will be around 300mb uncompressed, if not more.
Ps. I did not made/tested that sky idea, so it may be hard to do or not working in unreal etc.
Thanks for the tip. I will look into it when I get a chance.
If you’re looking for help with this, sadly i would not bother.
The guidance is wrong and broken and has not been updated. The advice here is great but vague enough to be diffcult to follow, and it seems cube maps are really not a great to make high detailed sky’s anymore. It just seems clunky, over complicated and outdated.
Not sure what the solution is, but it does seem that UE likes to make these things more difficult than they need to be.