Spark
€2.99/ month
Includes v19 · one version behind
- Previous versions of Prisma PTGI
- Each new release reaches Spark when the next one comes out
Shaderpack for Iris · Fabric + Sodium
PrismaPTGI
Light that really bounces. Voxel path tracing and ray tracing for Minecraft Java: exact shadows, colored light that spreads block by block, water that changes with the biome.
The light beam turns vanilla into Prisma · same spot, same moment
Vanilla vs Prisma
Drag the line. See what changes.
Every pair was captured from the same spot at the same time of day, switching the shaders off and on again. Vanilla Minecraft on the left, Prisma PTGI v20 on the HIGH profile on the right.
VANILLAPRISMA PTGI
VANILLAPRISMA PTGI
Ray tracing + path tracing
The sun comes in.
The sun comes in.
The room lights up.
The world around you is turned into voxels every frame. Rays travel through it to find out what the sun really reaches and where the light comes from.
- Ray traced shadows block by block near the player, with a shadow map out to 192 blocks for everything else.
- Path traced global illumination: the patch of sunlight on the floor brightens the walls and ceiling, while interiors stay dark where light can't reach.
- Doors and windows matter: open a door and the light comes in, close it and the room goes dark.
Reflections
Water that mirrors the real world
Reflections search the voxel world first, then the screen, then the sky and its clouds: islands show up in the water even when they are off screen, and the sun leaves a trail of light on the waves.
VANILLAPRISMA PTGI
Colored volumetric lighting
Every light has its own color.
Block light spreads through a colored 3D volume, block by block like Minecraft's own light, and path tracing adds the bounces. Faces turned toward a light get more of it, faces turned away stay in shadow.
Redstone
Lapis lazuli
Emerald
Soul torch
Torch
Redstone, lapis and emerald blocks glow by default. Diamond, gold, amethyst and ores can be switched on in the "Glowing Blocks" menu. A light held in your hand shines with the color of that item, in either hand.
One world, many skies
From cherry groves to snowy peaks.
A hand-tuned palette for the sky, sun and moon, volumetric clouds, and water that takes the color of its biome: turquoise in warm oceans, dark green in swamps.
Get Prisma PTGI
Pick your light.
Prisma PTGI is available through a Patreon membership. The plans differ only in which version you get: Spark has the previous versions, Prism always has the newest one. Spectrum is the same as Prism for those who want to support the project more.
Prism
€5.99/ month
Includes v20 · the latest version
- Always the newest version of Prisma PTGI
- All previous versions too
Spectrum
€12.99/ month
Includes v20 · the latest version
- The same as Prism
- For those who want to support the project more
Plans open the official MoonWalk Patreon in a new tab. Local taxes may be added at checkout. The license is included in every zip (LICENSE.txt): you can play, record and stream with it; re-uploading, sharing the file, modified versions and reuse in other shaders are not allowed.
v20LATEST · PRISM & SPECTRUM
Spark members get v19 (SHA-256 c9f14988dbde2ab509dd6dbeac3d58dfafdd1d83d6e6f0ac2c1d417b316808fa). Check the code of your file to be sure it's the official one.
How to install
- Download the zip from the release post on Patreon that matches your plan.
- Install Fabric, Sodium and Iris for your Minecraft version (the Iris installer sets up all three).
- Open the shaderpacks folder: in Minecraft go to Options → Video Settings → Shader Packs → Open Shader Pack Folder.
- Copy the zip into that folder. Do not unzip it.
- Select Prisma PTGI in the list and press Apply. Change quality with the Profile button (LOW to EXTREME).
Tip: press K in game to switch shaders off and on, the same way the comparisons on this page were made.
Versions
What changed, version by version.
The latest version is for Prism and Spectrum members, the previous one for Spark. Older versions are listed so you can see how the pack evolved.
v20 · Clear water
LATEST · PRISM & SPECTRUM- IMPROVEDWater has a color of its own even in the shallows, so it no longer looks like glass.
- IMPROVEDUnderwater redone: a clearer deep blue fog that lets you see about 20 blocks, softer light shafts.
- REMOVEDShoreline foam, the underwater view wobble and the extra underwater blur.
- NEWLicense file and copyright notice in every file of the pack.
v19 · Biome water & doors
SPARK- NEWBiome water: swamps murky green, warm oceans clear turquoise, cold oceans dark blue, also under water. New options for biome water and color intensity.
- NEWLight changes when you open or close doors, trapdoors and fence gates; fences no longer block light.
- IMPROVEDNew waves with sharper crests and ripples that calm down in the distance.
- IMPROVEDDirectional block light: faces turned toward a light get more of it, with a softer falloff. Stronger light bounces indoors.
- FIXEDA colored light held in the off hand turned white.
v18 · Light that spreads
ARCHIVED- NEWBlock light spreads block by block through a colored light volume, with path traced bounces on top.
- IMPROVEDRedstone, lapis, emerald, diamond, gold and amethyst blocks glow in much richer colors.
- FIXEDA dark square around torches and other light sources.
- FIXEDWater seemed to change depth depending on the viewing angle.
v17 · Glowing blocks
ARCHIVED- NEWGlowing blocks menu: redstone, lapis and emerald blocks on by default; diamond, gold, amethyst and ores optional.
- NEWThe light you hold takes the color of the item (soul torch blue, redstone torch red).
- IMPROVEDDarker interiors lit only by the light that comes in through windows and doors.
- FIXEDStairs, slabs, walls, beds and signs cast their real shape instead of full-block shadows.
- FIXEDDark lines along the edges of paths, farmland and slabs; black fire particles.
v16 · The Prisma palette
ARCHIVED- NEWHand-tuned Prisma color palette for sky, sunlight and moonlight; filmic tonemap.
- NEWNight sky with stars and the vanilla moon texture, phases included.
- IMPROVEDGolden sunsets, smaller and crisper cumulus clouds with grey bases, thin cirrus streaks.
- IMPROVEDDarker caves, nights and storms; warmer torches and cyan soul torches; sunlight through door and trapdoor windows.
v1–v15 · Early development
PRIVATE BUILDSPrivate test builds that were never released. They laid the groundwork: the voxel path tracer, ray traced sun and handheld light shadows, the colored light volume, volumetric clouds, water reflections and rain puddles.
Technical specs
Under the hood
| Requirements | Minecraft Java with Fabric, Sodium and Iris (compute shaders). Tested with Iris 1.11.4 on Minecraft 26.2. |
|---|---|
| Path tracing | Half resolution, 1 ray per pixel by default (up to 4), infinite bounces by reusing the previous frame, temporal + à-trous denoiser. |
| Voxel world | 128 × 96 × 128 blocks around the player, rebuilt every frame from the shadow pass. |
| Shadows | Ray traced near you (64 steps), 2048 shadow map out to 192 blocks. Stairs, slabs and doors cast their real shape. |
| Colored light | 3D RGBA volume with two propagation steps per frame, directional light, 18 light source types plus modded light blocks. |
| Sky | Physical atmosphere (Rayleigh, Mie, ozone) with the Prisma palette, volumetric cumulus, cirrus, stars and the vanilla moon with its phases. |
| Water | Crested waves, refraction, per-biome absorption, caustics, voxel + screen space reflections, puddles and ripples in the rain. |
| Profiles | LOW · MEDIUM · HIGH · ULTRA · EXTREME, plus a lighter mode without path tracing. |