Rethinking Voxels
by gri573
A voxel-based global illumination shader that uses voxelized scene data for accurate light bouncing. Produces colored lighting and realistic indirect illumination.
About Rethinking Voxels
Most shaders compute light from what is already on the screen, which is fast and breaks the moment something important is off-camera. Rethinking Voxels takes the other route: gri573 samples the world into a voxel grid and traces light through that grid, so what is around the corner still counts.
The practical difference is that light turns corners. A torch out of sight still lights the corridor leading to it, colour bleeds from a coloured block onto the stone beside it, and a room keeps its character when you turn your back on the window. Coloured shadows come out of the same system, so light through stained glass arrives tinted rather than grey.
Storing that voxel data costs video memory, which is why the requirement is an RTX 3060 or RX 6700 XT with 6 GB of VRAM rather than raw compute. It is Iris only on Minecraft 1.19 up through 1.21.10, it can be unstable, and it is built to take advantage of a PBR resource pack underneath even though it does not require one.
Rethinking Voxels effects, shown
The first two tiles are one idea seen from two angles. Sampling the world into voxels is what lets light turn a corner, and colouring each light source is what makes that visible: a torch you cannot see still lights the corridor leading to it, in its own hue. Everything else in this list is conventional, and it is there so the voxel work has an ordinary world to sit inside.
Rethinking Voxels ships 8 headline effects. The images here come from the pack itself. 8 of 8 are crops from Rethinking Voxels' own published screenshots, found by working through the gallery effect by effect, picking the frame where each one reads most clearly and cutting out the region where it is happening. The full frame at the top of this page is from the same gallery, so any crop can be traced back to its scene.
Voxel-based GI
The world is sampled into a voxel grid and light is traced through it, so what is around a corner still counts. That is the whole argument for the pack.
Colored lighting
Every light source carries its own colour into the voxel model, so a torch out of sight still lights the corridor leading to it in its own hue.
Volumetric clouds
Clouds carry real depth and, because the lighting is voxel-aware, the shade they throw reaches the terrain rather than stopping at the cloud layer.
PBR
A PBR resource pack is not required but changes more here than under most shaders, since voxel-traced light has genuinely different materials to bounce off.
Reflections
Reflective surfaces return the world above them, filling in the everyday mirroring that the voxel lighting is not the right tool for.
Bloom
A glow around bright sources, kept measured so it does not wash out the subtle indirect light the voxel model is working to produce.
Depth of field
The subject stays sharp while the background falls away, which suits a pack whose lighting rewards stopping and looking rather than running past.
Custom sky
A redrawn sky feeding the voxel lighting a plausible primary light source, so the traced result agrees with what the sky is showing.
How Rethinking Voxels changes Minecraft
Rethinking Voxels changes how light is computed rather than how blocks are drawn, and it starts by sampling the world into a grid. Everything after the first two entries exists so that those two have a world to sit in:
- Voxel-based GI: the world is sampled as voxels and light traced through that grid, so what is around a corner still counts toward the result.
- Colored lighting: every light source carries its own colour into the voxel model, so a torch out of sight still tints the corridor leading to it.
- Volumetric clouds: clouds carry real depth, and because the lighting is voxel-aware their shade reaches the terrain rather than stopping at the layer.
- PBR: a matching resource pack is not required but changes more here than under most shaders, since voxel light has real materials to bounce off.
- Reflections: reflective surfaces return the world above them, covering the everyday mirroring that voxel lighting is not the right tool for.
- Bloom: a glow around bright sources, kept measured so it does not wash out the subtle indirect light the voxel model works to produce.
- Overall direction: one of the most advanced free shaders available, demanding on memory rather than on compute, and still under active development.
Loaders Rethinking Voxels runs on
Rethinking Voxels system requirements
Baseline card: RTX 3060 / RX 6700 XT. Meters are scaled against a 12 GB VRAM / 32 GB RAM reference build.
The Rethinking Voxels balance sheet
| Strength | Accurate voxel-based GI |
| Strength | Beautiful colored lighting |
| Strength | Cutting-edge technology |
| Strength | Great with PBR packs |
| Trade-off | Extremely demanding |
| Trade-off | Iris only |
| Trade-off | Can be unstable |
| Trade-off | High VRAM usage |
How to install Rethinking Voxels
- 1Install Fabric or Quilt plus the Iris Shaders mod. The voxel work here has no OptiFine equivalent, so Iris is a hard requirement.
- 2Download the Rethinking Voxels .zip from the official page above and keep it as an archive.
- 3Bring Minecraft up on the Iris profile, choose Options, then Video Settings, and Shader Packs is the screen you want.
- 4Open Shader Pack Folder will bring up the right directory. Put the archive inside without unpacking it.
- 5Select Rethinking Voxels and press Apply. Watch video memory rather than frame rate after the first load, because that is where this pack's limit sits. If it will not start at all, the memory figure rather than the card model is usually the reason.
This is an Iris-only pack, and the voxel work has no OptiFine equivalent, so that requirement is absolute. Check your card's memory rather than its model number before you start: 6 GB of VRAM is the figure that decides whether this runs, and a fast card with 4 GB will struggle where a slower one with 8 GB will not.
Rethinking Voxels performance notes
Rethinking Voxels is an ultra-impact pack, and the cost is dominated by memory rather than by raw compute. Sampling the world into a voxel grid means keeping that grid somewhere, and video memory is where it lives.
The requirement is an RTX 3060 or RX 6700 XT with 6 GB of graphics memory and 8 GB of system RAM. The VRAM figure is the one that actually bites: a card with plenty of compute but 4 GB of memory will struggle here in a way the compute numbers would not predict.
It targets Minecraft 1.19 up through 1.21.10 on Iris only, and there is no OptiFine equivalent for the voxel work it depends on. The narrow range follows from being built against current loader capabilities rather than ported onto them.
Voxel resolution and range are the settings that reclaim the most, well ahead of shadow quality. The pack can be unstable on some configurations, so a sudden collapse rather than a gradual sag usually points at drivers or a mod conflict rather than at load.
Tags
What to turn down first in Rethinking Voxels
The voxel model is the point of this pack, so the tuning order protects it and gives up other things first.
- 1
Render distance: the voxel model scales with it, so this is both the frame saving and the memory saving.
- 2
Depth of field: off for playing. It contributes nothing to the lighting you came here for.
- 3
Reflection quality: the last of the cheap savings before you start damaging the coloured light itself.
How many people run Rethinking Voxels?
Second in the ultra tier on downloads, but its follower count sits close to Photon's, so proportionally more of its users track it. That fits a pack whose voxel lighting changes noticeably between releases and is worth updating for.
| Downloads of Rethinking Voxels on Modrinth | 12,255,249 on the maker's page |
|---|---|
| People following Rethinking Voxels for updates | 4,388 |
| Last Rethinking Voxels release by the author | 19 June 2025 |
| Where Rethinking Voxels sits on this site | 8 of 26 packs we could count, see the full ranking |
The Rethinking Voxels figures above were counted on 21 August 2026. Modrinth is the only platform with an open counter for Rethinking Voxels, so anyone downloading it elsewhere is not in this number.
Where Rethinking Voxels sits in our shortlists
Voxel-lit and current, which is why it sits on the shortlist for the heaviest machines:
Ready to install Rethinking Voxels?
Iris is not optional here. Our walkthrough handles Fabric and the Iris mod for the Minecraft version you want to run.
Installation GuideSomewhere to run Rethinking Voxels
Rethinking Voxels lights a scene from a voxel model, so coloured light bends round corners in tunnels and rooms. It is a pack for places that were dug and built, not for the first night in a dirt hut.
Rethinking Voxels builds its voxel model on your machine while you play, never on the host. What the server provides is the dug out, lit up place where that model has something to solve.
Set up a world for Rethinking VoxelsCode GUIDE5 is ours, and it applies to a Rethinking Voxels world from the link above.Last updated . This page is rebuilt when its own figures change, not on every deploy.