Compatibility
Minecraft: Java Edition
1.21.x
1.20.5–1.20.6
Platforms
Tags
Creators
Details
Licensed GPL-3.0-only
Published 7 months ago
Alpha Piscium
High-quality realistic Minecraft shaderpack featuring global illumination, volumetric clouds, atmospheric scattering, and stunning visual effects.
Official Website link: https://alphapiscium.org/
Discord server link: https://discord.gg/E2Uq2MmHgq
Features
- Real-time Global Illumination
- Reservoir-based SpatioTemporal Importance Resampling (ReSTIR) based Screen-Space Global Illumination
- ReBLUR based denoising
- Realistic, real-time, and fast Atmospheric Scattering
- Real-time Volumetric Clouds
- High-quality adaptive Shadows
- Rectilinear Texture Warping (RTWSM)
Installation
- Download the Alpha Piscium shaders for Minecraft from Modrinth or GitHub Release.
- Install Iris shader loader.
- Open the Minecraft launcher and choose the Iris profile you just created with the version you're playing.
- Launch Minecraft.
- Go to Options → Video Settings → Shader Packs, then click Open Shader Pack Folder.
- Move the downloaded ZIP file into this folder (
.minecraft/shaderpacks). - In-game, select the newly installed pack from the shaders list. (If you select a shader pack using Iris, its filename will turn yellow.)
- Click Done or Apply and the shader will be loaded.
FAQ
- No lighting at night: Please use PBR resource packs. For vanilla style, SPBR is recommended. Otherwise, try Patrix.
- Can't load shaderpack: Please use Iris with version 1.7 or higher.
- Everything goes dark when turning back: This is due to the limitations of screenspace techniques. There isn't a perfect way to fix this.
- Intel GPU: Alpha Piscium uses cutting-edge graphics technology. Unfortunately, Intel doesn't maintain their OpenGL driver well, so Intel GPUs are not supported.
- AMD GPU: Check if your GPU driver is newer than 22.7.1. If older, please update your driver.
- Other loading errors: Press Ctrl+D in Iris's shaderpack selection screen, then reload the shaderpack. Make an issue with the error message and the relevant files in
.minecraft/patched_shadersas shown in the error message.
Roadmap
1.9 Specular GI
- Add specular GI
2.0 World Space Tracing
- Add voxelization and voxel tracing
2.1 DRT Update
- Release Skibidi DRT
- HDR mod support?
2.2 Volumetrics shadowing
- Add cloud shadowing to volumetrics
- Add screen space shadow to volumetrics
2.3 Local fog
- Add ground fog
2.4 Cloud shadow
- Add cloud shadow to terrain rendering
- Add cloud to reflection/GI
2.5 Cloud update part 1
Improve cloud lighting
- Add altocumulus
- Rewrite cirrus modeling
2.6 Cloud udpate part 2
- Rewrite cumulus modeling
- Add stratocumulus and nimbostratus
2.7 Upscaling???
- Add FSR 3.1 (no framegen)
2.8 Parallax mapping???
- Add steep/smooth parallax mapping
- Add parallax mapping shadow
License
Files under the scripts directory are licensed under the MIT License. All other files are licensed under the GNU General Public License v3.0.


