inkling

Reveal arbitrary ASCII art as a progress indicator.

A normal progress bar maps a scalar 0..=1 onto how much of a line is filled. inkling generalises that to two dimensions: it maps progress onto the order in which the glyphs of a picture appear. Give it a dragon and it paints the dragon as your task runs.

Quick start

The easy front door is Loader: make one with a total, advance it from anywhere, and a living reveal paints itself until you finish.

use inkling::Loader;

let loader = Loader::new(100);
for _ in 0..100 {
    // ... a slice of work ...
    loader.inc(1);
}
loader.finish();

Or wrap any iterator and forget about it:

use inkling::ProgressIteratorExt;

for _item in (0..100).inkling() {
    // ... work ...
}

The one idea

Everything turns on a single abstraction, the [RankMap]: every ink cell of the art is assigned a reveal rank in 0..=1, and a cell is visible exactly when rank <= progress. Because rank is fixed and monotonic, the reveal can never run backwards, any progress value renders directly (it is seekable and resumable), and the whole thing is pure.

How ranks are assigned is the single pluggable seam: an [Ordering]. The flagship Geodesic ordering traces the "spine" of the art and reveals along it, so a serpent paints from one tip to the other, around every coil, with no per-art configuration.

use inkling::{Art, ordering::{Ordering, Geodesic}};

let art = Art::parse("/\\__/\\\n\\____/");
let ranks = Geodesic::default().rank(&art);

// The pure, dependency-free view: render the half-revealed frame as text.
let frame = inkling::frame::to_string(&art, &ranks, 0.5);
assert_eq!(frame.lines().count(), art.height() as usize);