Interruptions

a field of short line segments at random rotations. A noise threshold omits some of the segments. The grid is the order, and the rotations and gaps are the disorder. It is after Molnár, in the spirit of her Interruptions (1969). Click to recreate a new variation.

Run

swift run --package-path Examples Example-Recreations-VeraMolnar-Interruptions

Source

Examples/Recreations/VeraMolnar/Interruptions/Sketch.swift

//  Recreation after Vera Molnár — in the spirit of her "Interruptions" (1969)
//  and her order-vs-disorder line works. A homage, not a reproduction.
//
//  Ported from the p5.js sketch week-1/vera-1 (MIT) in
//  https://github.com/eaviles/rtp-sfpc-f21-p5 — itself a p5 port of Zach
//  Lieberman's openFrameworks sample for the RTP class at SFPC, Fall 2021
//  (https://github.com/ofZach/RTP_SFPC_F21). Reworked for Ollin's API.

import Foundation
import Ollin

/// A 40×40 field of short line segments at random rotations, with some omitted
/// where a Perlin-noise field dips below a threshold — Vera Molnár's interplay
/// of order (the grid) and disorder (the rotations and gaps). **Click to
/// recreate**: each click re-rolls the seed for a new variation.
///
/// The original is a static, seeded still image. Here `draw()` re-applies the
/// seed every frame so it looks static, and `mousePressed()` bumps the seed —
/// avoiding any need for `noLoop()`/`redraw()`. Demonstrates `withState { }` with
/// `translate`/`rotate`, plus `drawLine`, `random`, and Perlin `noise`.
@main
final class Interruptions: Sketch {
    var seed = 0

    override func setup() {
        stroke(.black)
    }

    /// Each click is a fresh roll of the disorder.
    override func mousePressed() {
        seed += 1
    }

    override func draw() {
        background(.white)
        randomSeed(seed)   // re-seed each frame so the image is stable until a click
        noiseSeed(seed)

        // Canvas-relative: a 1/16 inset, the segments spanning it edge to edge,
        // with each ~0.3 of the inset long.
        let margin = shortSide * 0.0625
        let half = margin * 0.3
        let g = grid(columns: 40, rows: 40, padding: .all(margin), distribution: .spanning)
        for dot in g.points {
            withState {
                translate(dot.position)
                rotate(random(0, .tau))
                // 0.7 (the source uses 0.6) keeps the intended density
                // against Ollin's contrast-calibrated noise: gate is raw < 0.2.
                if noise(Double(dot.column) * 0.1, Double(dot.row) * 0.1) < 0.7 {
                    drawLine(-half, 0, half, 0)
                }
            }
        }
    }
}