ratatui-opentui-loader

KITT-style (Knight Rider) scanner/loader widget for ratatui.

Inspired by the opencode bottom-left spinner.

Demo

Features

Bidirectional scanner with color trail (■ active, ⬝ inactive)
Trail dissolves at edges — no hard bounce
Inactive dots "breathe" (fade in/out) during hold phases
Asymmetric timing: brief pause at right edge, longer rest at left
34 built-in themes matching opencode (Dracula, Gruvbox, Catppuccin, Nord, Tokyonight, etc.)
Custom accent color support
Invertible trail for light backgrounds
Implements ratatui::Widget
Also exposes into_line() for composing into larger widgets

Usage

use ratatui_opentui_loader::{KittLoader, Theme};

// Create a loader and tick it each frame (~40ms)
let mut loader = KittLoader::with_theme(Theme::Dracula);
loader.tick();

// As a Widget (auto-sizes to area)
frame.render_widget(&loader, area);

// As a Line (for composing)
let line = loader.into_line(20);

// With a custom color
let mut loader = KittLoader::with_color(Color::Rgb(236, 72, 153));

// Inverted trail for light backgrounds
let mut loader = KittLoader::with_theme(Theme::Github).inverted(true);

Themes

All opencode dark-mode themes are built in:

Opencode, Dracula, Gruvbox, Catppuccin, Catppuccin Frappe, Catppuccin Macchiato, Nord, Tokyonight, Solarized, Rosepine, Ayu, Monokai, One Dark, Kanagawa, Material, Everforest, Github, Amoled, Aura, Carbonfox, Cobalt2, Cursor, Flexoki, Matrix, Mercury, Nightowl, Palenight, Shades of Purple, Synthwave '84, Vesper, Zenburn, Vercel, Orng, Osaka Jade.

Run the example

cargo run --example demo

Use left/right arrows to page through all themes.

License