orhun/ratty

Ratty: A GPU-rendered terminal emulator with inline 3D graphics 🧀
^{Inspired by TempleOS | Built with Rust & Ratatui}

"Rodent-obsessed developer creates Ratty to bring 3D graphics to the command line" - The Register
"This New Terminal is Absurd (But Totally Fun)" - It's FOSS
"10 weird OSS projects you need right now... " - Fireship
"Your terminal can render in 3D now, and Rust made it surprisingly usable" - MakeUseOf

Features

• Spinning rat cursor (customizable)
• Traditional 2D and new 3D mode!
• Inline 3D objects
• GPU-backed text rendering
• Image support (via Kitty Graphics Protocol >:()

▶️ Watch the demo video here!
📚 Read the behind the scenes blog post here!

3D mode

Ever wondered what's behind the terminal? Press Ctrl+Alt+Enter!

Installation

Requirements:

• A GPU / graphics stack supported by Bevy and wgpu
• Melted cheese (optional but recommended)

crates.io

cargo install ratty

Arch Linux

sudo pacman -S ratty

Nix

See the Nix packaging docs for flake, NixOS, and Home Manager usage.

nix run github:orhun/ratty

Binary releases

Prebuilt binaries are available on the GitHub releases page for direct download.

From Git

Requirements:

• Rust toolchain with Cargo
• on Bazzite / Bluefin: sudo rpm-ostree install gcc fontconfig-devel wayland-devel (then reboot)
• on Debian / Ubuntu: sudo apt-get update ; sudo apt-get install gcc pkgconf libfontconfig-dev libwayland-dev
• on Fedora: sudo dnf install gcc fontconfig-devel wayland-devel

cargo install --git https://github.com/orhun/ratty

Configuration

The default configuration file is available in config/ratty.toml.

You can copy this file to $HOME/.config/ratty/ratty.toml and customize it.

Changing the cursor

[cursor.model]
path = "CairoSpinyMouse.obj"
scale_factor = 6.0
brightness = 0.5
x_offset = 0.5
plane_offset = 18.0
visible = true

[cursor.animation]
spin_speed = 1.4
bob_speed = 2.2
bob_amplitude = 0.08

For cursor.model.path, Ratty supports both .obj, .glb, and .stl assets.

Other useful cursor fields are:

• scale_factor: scales the model relative to the terminal cell size
• brightness: adjusts the cursor material brightness
• x_offset: shifts the cursor model horizontally inside the cell
• plane_offset: pushes the cursor away from the warped terminal surface in 3D mode
• visible: show the custom 3D cursor model instead of only the terminal cursor

Key Bindings

Key	Action
Ctrl+Alt+C	Copy selection
Ctrl+Alt+V	Paste clipboard
Ctrl+Alt+Enter	Toggle 2D / 3D mode
Ctrl+Alt+M	Toggle Mobius mode
Ctrl+Alt+Up	Increase warp
Ctrl+Alt+Down	Decrease warp
Alt+PageUp	Scroll one page up
Alt+PageDown	Scroll one page down
Alt+Up	Scroll one line up
Alt+Down	Scroll one line down
Ctrl+=	Increase font size
Ctrl+-	Decrease font size
Ctrl+Alt+0	Reset font size

Inline 3D objects

Ratty uses its own protocol, the Ratty Graphics Protocol, to place inline 3D objects in terminal space.

RGP supports:

• registering .obj, .glb, and .stl assets by path
• placing them at terminal cell anchors
• animation, scale, color, depth and other attributes

There is a Ratatui widget called ratatui-rgp available in widget/ if you want to build your own terminal applications that involve inline 3D objects.

Examples

Big rat

Places a single oversized rat directly in your terminal:

Document

TempleOS-inspired document demo with editable text and embedded inline 3D objects:

Draw

Split-pane drawing demo with a 2D canvas on the left and a live 3D preview on the right:

Rubik's cube

Interactive 3D Rubik's cube demo:

Mobius Chess

A Mobius-strip chess demo:

Apps

Here are some applications explicitly built around Ratty's Graphics Protocol:

Ratscad

Terminal CAD:

Ratty-runner

Endless runner built for Ratty:

ComChan

A blazingly fast serial monitor with plotter TUI and 3D telemetry

Architecture

Rendering pipeline

The terminal surface currently uses ratatui for the UI buffer, parley_ratatui for text shaping/rendering and Bevy for scene presentation.

Current workflow:

1. PTY output is parsed by vt100 and drawn into a Ratatui buffer on CPU
2. parley_ratatui shapes the buffer with Parley and records it as a Vello scene
3. The scene is handed to Bevy's render world through a double-buffered exchange (scenes are recycled between frames, never cloned or re-recorded)
4. Vello renders the scene on Bevy's render-world device into a plain Rgba8Unorm storage texture, with no CPU readback in between
5. That storage texture is copied into an Rgba8UnormSrgb present texture (sampled through an sRGB view, so Vello's sRGB-encoded output is decoded on sample instead of re-encoded), which Bevy presents in the 2D and 3D scenes

The terminal image is fully GPU-resident: the only data crossing from the main world to the render world each frame is the recorded scene, not pixels.

Endorsements

• "This is like a legitimately cool project but also I just spent like 20 minutes adjusting the config for the rat spinning to see him spin faster and more erratically and it cracked me up" - @vimlena.com

• "These kinds of experiments are where creativity is born." - @Coko7

• "No comments. Just support." - @Raphamorim (creator of Rio terminal)

• "tetro-tui running in Ratty" - @Strophox

License

All code is licensed under The MIT License.

^{🦀 ノ( º \_ º ノ) - respect crables!}

Credits

Ratty logo designed by @Strophox & @Harunocaksiz

Copyright

Copyright © 2026, Orhun Parmaksız

^{The author does not have a rat under the hat!}