Raffine

A high-performance, affine transformation library for Rust, inspired by Python's Affine package(https://github.com/rasterio/affine).

📦 Installation

Add this to your Cargo.toml:

[dependencies]
raffine = "0.2"

🎯 Quick Start

use raffine::Affine;

fn main() {
    // Create basic transformations
    let translation = Affine::translation(10.0, 20.0);
    let rotation = Affine::rotation(45.0, None);
    let scale = Affine::scale(2.0, Some(3.0));

    // Transform a point
    let point = (1.0, 1.0);
    let result = translation * point;
    println!("Translated point: {:?}", result); // (11.0, 21.0)

    // Transform an integer point
    let ipoint = (1isize, 1isize);
    let iresult = translation * ipoint;
    println!("Translated point: {:?}", iresult); // (11, 21)

    // Compose transformations (applied right to left)
    let composite = translation * rotation * scale;
    let transformed = composite * point;
  
    // Invert transformations
    let inverse = (!translation).unwrap();
    let original = inverse * result;
    assert_eq!(original, point);
}

🌍 GIS Integration

GDAL Compatibility

// Import from GDAL GeoTransform format
let gdal_params = [100.0, 1.0, 0.0, 200.0, 0.0, -1.0];
let transform = Affine::from_gdal(&gdal_params);

// Export to GDAL format
let (c, a, b, f, d, e) = transform.to_gdal();

⚙️ Configuration

Precision Control

use raffine::{set_epsilon, get_epsilon};

// Set global precision for floating-point comparisons
set_epsilon(1e-10);

// Custom precision for specific comparisons
let t1 = Affine::identity();
let t2 = Affine::translation(1e-11, 0.0);
assert!(t1.almost_equals(&t2, Some(1e-10)));

📄 License

MIT license (LICENSE or http://opensource.org/licenses/MIT)

🙏 Credits

This library is derived from Casey Duncan's Planar package and inspired by Python's Affine package.