Screenshot 1 of 5. Village scene with a pink-stone well, orange-roofed houses and hay bales under a cloudy sky, rendered with Principal.
What Principal works with.
| Platform | Java Edition |
|---|---|
| Loaders | Iris, OptiFine |
| Minecraft versions | 1.16, 1.16.5, 1.17.1, 1.18.2, 1.19.4, 1.20.6, 1.21.11, 26.1.2, 26.2 |
Principal, titled La Flòr Principal on its own page, is an atmospheric shader pack for Minecraft Java on Iris and OptiFine. It sits between semi-realistic and vanilla-like, with cinematic skies, volumetric clouds, PBR lighting and weather-reactive fog. It installs on the player's own machine only and is built for mid-range GPUs.
Shader loaders and versions
- Iris and OptiFine: Minecraft 1.16 to 26.2.
Sky, clouds and weather
The sky follows a Rayleigh-style scattering model. Midday gives a cerulean dome, while dawn and dusk pass through amber and violet into the horizon fog, with a tuned golden-hour window around 6:00 AM and 6:00 PM. At night a procedural star field fades out near the horizon.
Clouds use domain-warped fractional Brownian motion, which avoids the repeating grid seen in simpler packs. They drift with a wind vector, darken and cool on the underside, and pick up orange-red edges at sunset. Fog changes colour with the sky, and rain raises its density by up to roughly four times.
Lighting and PBR
- Terrain, entities and held items share one PBR pipeline that reads normal and specular maps from LabPBR-compliant resource packs.
- Without a PBR pack you still get directional sun and moon light, specular highlights and a time-of-day ambient tint, from lavender-pink mornings to blue-violet midnights.
- Torches cast a warm amber point light with a directional bias, so caves feel lit rather than just brightened.
- An underwater pass adds blue-green volume with depth-based darkening.
Installing Principal
- 1.Install Iris (on Fabric or NeoForge) or OptiFine. Principal needs no other dependency.
- 2.Put the pack's .zip in the shaderpacks folder. The shader install guide covers the steps for each loader.
- 3.Open Video Settings, then Shader Packs, and select Principal. If it fails to load, try the shader troubleshooting guide.
Questions about Principal.
3 questions
How do I install Principal?
Install Iris or OptiFine first, then place the Principal .zip in your shaderpacks folder. Launch Minecraft, open Video Settings, choose Shader Packs and select Principal from the list. It has no further dependencies, and it only runs on Java.
Does Principal work with Iris and OptiFine?
Yes. Both loaders have releases for it, and it needs nothing beyond the loader itself. On Iris you select it under Video Settings, Shader Packs, the same menu path used for other shader packs.
Does Principal need a PBR resource pack?
No. It improves lighting, specular highlights and ambient tint on its own. A LabPBR-compliant resource pack adds real specular reflections and surface depth through its normal and specular maps.
