Genuary 2025 day 2

// By Roni Kaufman

// https://ronikaufman.github.io

​

// Made for Genuary 2025

// Day 2: Layers upon layers upon layers.

​

function setup() {

  createCanvas(500, 500);

  noLoop();

}

​

function draw() {

  background(5);

  let margin = 60;

  let nLayers = 10;

  let u = (width-2*margin)/(2*nLayers-1);

  let s = nLayers*u;

  strokeWeight(1.5);

  strokeCap(SQUARE);

  for (let i = 0; i < nLayers; i++) {

    let z = margin + i*u;

    fill(rainbow(i/(nLayers-1), "b0"));

    noStroke();

    square(z, z, s);

    stroke("#fffbe6");

    noFill();

    truchet(z, z, s, nLayers);

    stroke(5);

    square(z, z, s);

  }

}

​

function truchet(x0, y0, s, n) {

  let u = s/n;

  for (let i = 0; i < n; i++) {

    let x = x0+i*u;

    for (let j = 0; j < n; j++) {

      let y = y0+j*u;

      if (random() < 1/2) {

        arc(x, y, u, u, 0, PI/2);

        arc(x+u, y+u, u, u, PI, 3*PI/2);

      } else {

        arc(x+u, y, u, u, PI/2, PI);

        arc(x, y+u, u, u, 3*PI/2, TAU);

      }

    }

  }

}

​

function rainbow(t, alpha) {

  let palette = ["#ef562f", "#fc8405", "#f9d531", "#abcd5e", "#62b6de"];

  let i = floor((palette.length-1)*t);

  let amt = fract((palette.length-1)*t);

  return lerpColor(color(palette[i%palette.length]+alpha), color(palette[(i+1)%palette.length]+alpha), amt);

}