I made this quick tutorial to show up how it is to set up the new Volumetric Clouds feature that will be released when UE4.26 is launched (expected at October 2020). You can watch it and if you want to get hands dirty, you will need to download the engine source code and build it, specifically the Dev-Rendering branch and enable the volumetric plugin at the editor. I developed in 2017 a volumetric cloud system which is at the Marketplace (release 1.2) and is currently being reworked into a release 1.5 which will offer similar results, with ability to create also 3 layers of clouds, with weather effects: lightning, rain, snow, thunder, spherical rendering for planets, stylized examples, and a library of different noise functions which you can use to create volume textures to elaborate intricate cloud shapes . The expected release is around September, so keep your eyes on the marketplace forums for the release.
Thanks, but much of the work is on Epic. I just tried to replicate what they mentioned at their live stream with a slow pace and show that for a small sky you can accomplish a scene, with some creativity, in a very easy way. There is much more besides what I have shown. The key point for a world cloud system is the textures representing the mask (spots where clouds will appear and their extent and basic shape) and the noise texture (the volume one representing the cloud details), because when the scale grows the repetition is clear, and besides it looks ok from the ground, the aerial and space view is quite obvious repetitive, so you will want a way to generate the mask texture in a procedural way, with very low resolution, maybe even using the virtual texture option for this because it will be the cheapest, but I still need to test it and figure out how.
Anyway the performance is really appealing in my opinion with even old gpus for today’s standards.
By the way there is an example cloud material for the new system in the dev-rendering branch so you dont have to make your own if you dont want to. This commit should give enough clues about where it is to be found:
I have checked that. The material crashes with a noise shape > 64x64x64, like the one there with 128x128x128. It uses a weather texture to tell where to form clouds, but that is tilled and too repetitive, exactly what it should not be for a planetary scale, the result for that material is not pretty and thats why I didn’t showed in the tutorial. Currently I think there is still too much they didn’t pushed into GitHub and most of those are clearly not what we will get. Again, the key will be the ability for the people to author the textures (mainly the mask) for two purposes: local scene and planetary scene, being the last one given you the ability to move from ground view to space view and see a non-tiling cloudscape. The ways you can think about the material is not that much of a variance, but the textures definitely will need to be procedural generated for the planetary scene purpose.
If you watch the tutorial you will see that the volumetric cloud blueprint needs a proper material to show anything. A volume material type with 0 plugged at Extintion pin will produce a clean sky if the directional light and a sky is added at the scene.
Important: it might happen that some textures are not present on later previews/releases, so it is important to at least first download the engine source around August 8th 2020, save those textures and then you can use whatever 4.26+ preview or release available.
