#grid #image-processing #halftone

rotated-grid

Rotated grid calculations for CMYK halftone dithering and more

2 releases

0.1.1 Jul 8, 2023
0.1.0 Jul 2, 2023
0.0.1 Jul 1, 2023

#638 in Images

EUPL-1.2

12KB
197 lines

Rotated grids in Rust

🎨 For halftone dithering and more.


This crate provides a generator for enumerating grid coordinates at a specified frequency along a rotated grid. This can come in useful e.g. when you want to create halftone dithering grids for CMYK processing:

CMYK grid examples

See e.g. my opencv-cartoon-effect repo for an almost-real-world usage example.

Usage example

use rotated_grid::{Angle, GridPositionIterator, GridCoordinate};

const WIDTH: usize = 16;
const HEIGHT: usize = 10;

fn main() {
    let halftone_grids = [
        ("Cyan", 15.0),
        ("Magenta", 75.0),
        ("Yellow", 0.0),
        ("Black", 45.0),
    ];
    
    for (name, angle) in halftone_grids {
        println!("{name} at {angle}°", name = name, angle = angle);
    
        let grid = GridPositionIterator::new(
            WIDTH as _,
            HEIGHT as _,
            7.0,
            7.0,
            0.0,
            0.0,
            Angle::<f64>::from_degrees(angle),
        );
    
        let (_, expected_max) = grid.size_hint();
        let mut count = 0;
    
        for GridCoordinate { x, y } in grid {
            println!("{x}, {y}", x = x, y = y);
            count += 1;
        }
    
        assert!(count <= expected_max.unwrap())
    }
}

You can run the example application using

cargo run --package cmyk

No runtime deps