Stratos
- By
Client-sided cloud & atmospheric mod allowing for performant shader-like visuals.
Stratos
Clouds for the Atmosphera suite on Minecraft Forge 1.20.1: weather-driven, volumetric clouds that look like a shaderpack's, at about the cost of vanilla's, without a shaderpack. Later releases add the sky itself (see the roadmap).
Client-only. Never required on a server, never blocks joining one. Off while a shaderpack is active (packs draw their own clouds) and under Fabulous graphics.
What it does (0.1.0)
- Three cloud decks. A volumetric low deck of fair-weather cumulus; thin altocumulus above it; high, wispy cirrus that the faster wind aloft drags sideways.
- Weather. Rain turns the sky into a low grey sheet, thunder builds towering storm clouds, dry biomes have fewer clouds and cold ones flatter ones. Clouds drift with the shared wind (Gale's, when installed).
- Light. A silver lining towards the sun, dark storm bases, clouds glowing after sunset, moonlight at night, haze with distance, and a curved layer that sinks to the horizon.
- Distant terrain. NeoVoxy and Voxy LODs hide the clouds behind them; Distant Horizons too (not yet tested in game).
- Works with Lumis. Lumis draws no clear-sky light rays or lens flare through Stratos's clouds.
- Styles: STRATOS (realistic, default), SOFT, BLOCKY (vanilla-like cells). Resource packs can replace them
(
assets/stratos/styles/*.json).
Cost
One post pass at a fraction of the screen's resolution, smoothed over frames.
| Quality | Resolution | Target GPU time (1440p) |
|---|---|---|
| LOW | 1/4, no history | ≤ 0.05 ms |
| MEDIUM (default) | 1/4, temporal | ≤ 0.15 ms |
| HIGH | 1/2, temporal | ≤ 0.25 ms |
These are targets; they are not yet measured. Only AMD hardware has been tested.
Install
- Forge 1.20.1 (47.x) and AtmospheraLib 0.7.0 or newer.
- Put the Stratos jar in
mods/. - Options are on the "Stratos (clouds)" page in Video Settings (with Xenon or Embeddium), and in
config/Atmosphera/stratos-client.toml.
Roadmap
| Release | Theme |
|---|---|
| 0.1.0 "Deck" | Clouds (this release) |
| 0.2.0 "Shade" | Cloud shadows on the ground and light beams through cloud breaks (with Lumis) |
| 0.3.0 "Firmament" | Stratos's own sky: scattering, sun and moon, stars, twilight |
| 0.4.0 "Mirror" | Clouds in Torrente's water reflections |
| 0.5.0 "Storm" | Anvils, rain shafts, lightning inside clouds, clouds on mountains |
| 0.6.0 "Air" | Biome fog and haze |
| 0.7.0 "Optics" | Halos, sun dogs, rainbows, the green flash |
| 0.8.0 "Night" | Aurora, noctilucent clouds, meteors |
Details: docs/roadmap/STRATOS-ROADMAP.md and docs/STRATOS-DESIGN.md in the Atmosphera repository.
Licence
All Rights Reserved. Copyright (C) 2026 SolarBiscuit. The source is public so it can be read. Unmodified jars may be
included in modpacks with credit; everything else needs permission. See LICENSE. Stratos needs
AtmospheraLib, which is a separate GPL-3.0 work.
Stratos is an independent project, not affiliated with Mojang Studios, Microsoft, Minecraft Forge, or the authors of any mod, resource pack or shaderpack it works with.
Stratos Team
