themalingadingdong

Base24 color palette generator using Hellwig-Fairchild CAM16 color appearance model with APCA contrast validation. Outputs tinted-theming compatible schemes.

Features

• Perceptually uniform accents: Uses Hellwig-Fairchild CAM16 (JMh) for accurate color appearance
• APCA contrast validation: Ensures accessibility per WCAG 3.0 guidelines
• Helmholtz-Kohlrausch effect: Accounts for chromatic brightness perception
• Interactive TUI: Real-time preview with parameter adjustment
• Import/Export: Load existing Base16/Base24 schemes, output YAML or JSON

Installation

cargo install --path .

Usage

Generate a dark theme

themalingadingdong -b "#1d2021" -f "#ebdbb2" --name "gruvbox-dark"

Generate a light theme

themalingadingdong -b "#fbf1c7" -f "#3c3836" --name "gruvbox-light"

Interactive mode

themalingadingdong -b "#000000" -f "#ffffff" --name "my-theme" -i

Import and edit existing scheme

themalingadingdong --input scheme.yaml -i

Generate both variants

themalingadingdong -b "#1d2021" -f "#ebdbb2" --name "gruvbox" --variant both -o gruvbox

JSON output

themalingadingdong -b "#282828" -f "#ebdbb2" --name "theme" --format json

Color Input

Accepts any CSS color format via csscolorparser:

• Hex: #1d2021, 1d2021
• RGB: rgb(29, 32, 33), rgba(29, 32, 33, 1)
• HSL: hsl(195, 6%, 12%)
• OKLCH: oklch(0.25 0.01 240)
• Named: black, rebeccapurple

Configuration

Save/load TOML configuration files:

# Save current settings
themalingadingdong -b "#000" -f "#fff" --name "dark" --save-config dark.toml

# Load from config
themalingadingdong --config dark.toml

Accent Optimization

The solver optimizes accent colors (base08-base0F, base10-base17) for:

• Uniform lightness: All accents share similar perceived brightness
• Minimum contrast: Guaranteed APCA floor against background
• Maximum colorfulness: Vibrant colors within sRGB gamut

Key parameters:

Flag	Description	Default
--min-contrast	APCA floor for base08-base0F	45
--extended-min-contrast	APCA floor for base10-base17	60
--target-j	Target lightness (J')	65
--target-m	Target colorfulness (M)	40
--j-weight	Uniformity vs vibrancy (0-1)	0.5

Hue Overrides

Customize accent hues (in degrees):

themalingadingdong -b "#000" -f "#fff" --name "theme" \
  --hue-08 30 \   # Red
  --hue-0b 120    # Green

Default hues: Red=25, Orange=55, Yellow=90, Green=145, Cyan=180, Blue=250, Purple=285, Magenta=335

Shell Completions

themalingadingdong --completions bash > ~/.local/share/bash-completion/completions/themalingadingdong
themalingadingdong --completions zsh > ~/.zfunc/_themalingadingdong
themalingadingdong --completions fish > ~/.config/fish/completions/themalingadingdong.fish

Architecture

Input (CSS colors)
    |
    v
Hellwig-Fairchild CAM16 (JMh)  <-- Perceptually uniform color space
    |
    v
COBYLA Solver                   <-- Multi-objective optimization
    |                               (contrast, uniformity, colorfulness)
    v
APCA Validation                 <-- Accessibility verification
    |
    v
Base24 Scheme (YAML/JSON)       <-- tinted-theming compatible output

License

MIT