README

An immutable, memory-efficient Color class for PHP with support for RGB and HSL color spaces, CSS color names, and WCAG accessibility features.

License | Changelog | Documentation

Description

This package provides a comprehensive Color class for working with colors in PHP. The class is designed to be:

Immutable - Color values cannot be changed after creation, ensuring predictability and thread safety
Memory-efficient - Colors are stored internally as a 4-byte binary string
Feature-rich - Supports RGB, HSL, hex strings, CSS color names, and accessibility calculations
CSS-compatible - Outputs to modern CSS color formats (hex, rgb, hsl)

Development and Quality Assurance / AI Disclosure

Claude Chat and Claude Code were used in the development of this package. The core classes were designed, coded, and commented primarily by the author, with Claude providing substantial assistance with code review, suggesting improvements, debugging, and generating tests and documentation. All code was thoroughly reviewed by the author, and validated using industry-standard tools including PHP_Codesniffer, PHPStan (to level 9), and PHPUnit to ensure full compliance with PSR-12 coding standards and comprehensive unit testing with 100% code coverage. This collaborative approach resulted in a high-quality, thoroughly-tested, and well-documented package delivered in significantly less time than traditional development methods.

Requirements

PHP ^8.4
ext-ctype
galaxon/core

Installation

composer require galaxon/color

Quick Start

use Galaxon\Color\Color;

// Create colors from various formats
$red = new Color('red');
$orange = new Color('#ff8000');
$purple = Color::fromRgba(128, 0, 255);
$green = Color::fromHsla(120, 1.0, 0.5);

// Access color properties
$color = new Color('#ff8040');
$color->red;         // 255
$color->hue;         // 20.0
$color->lightness;   // 0.625

// Modify colors (returns new instance)
$darkRed = $red->withLightness(0.3);
$transparent = $red->withAlpha(128);

// Color operations
$mixed = $red->mix($blue, 0.5);
$complement = $red->complement();

// Accessibility
$textColor = $background->bestTextColor();  // 'black' or 'white'
$ratio = $color1->contrastRatio($color2);

// Output formats
echo $color->toHex();        // '#ff8040ff'
echo $color->toRgbString();  // 'rgb(255 128 64 / 1)'
echo $color->toHslString();  // 'hsl(20deg 100% 62.5% / 1)'

Classes

Color

Immutable class for color manipulation with support for:

RGB and HSL color spaces with automatic conversion
CSS color names (147 standard names plus 'transparent')
Hex string parsing (3, 4, 6, or 8 digits)
Immutable modification methods (withRed, withHue, etc.)
Color mixing and complementary colors
WCAG accessibility calculations (contrast ratio, text color selection)
Multiple output formats (hex, rgb(), hsl())

Testing

The library includes comprehensive test coverage:

# Run all tests
vendor/bin/phpunit

# Run with coverage (generates HTML report and clover.xml)
composer test

License

MIT License - see LICENSE for details

Contributing

Contributions are welcome! Please:

Fork the repository
Create a feature branch
Add tests for new functionality
Ensure all tests pass
Submit a pull request

For questions or suggestions, please open an issue.

Support

Issues: https://github.com/mossy2100/Galaxon-PHP-Color/issues
Documentation: See docs/ directory for detailed class documentation
Examples: See test files for comprehensive usage examples

Changelog

See CHANGELOG.md for version history and changes.

galaxon / color

Maintainers

Details