const N = 2 ** order;

const total = N * N;

​

let video;

let vScale = 16;

​

let path = [];

​

function setup() {

  createCanvas(480, 480);

​

  for (let i = 0; i < total; i++) {

    path[i] = hilbert(i);

    let len = width / N;

    path[i].mult(len);

    path[i].add(len / 2, len / 2);

  }

​

  pixelDensity(1);

  video = createCapture(VIDEO);

  let r = 320/ 240;

  video.size(r*width / vScale,height / vScale);

  //video.hide()

}

​

function draw() {

  background(0);

  stroke(255);

  strokeWeight(2);

  noFill();

  beginShape();

  for (let i = 1; i < path.length; i++) {

    vertex(path[i].x, path[i].y);

  }

  endShape();

​

  video.loadPixels();

let delta = video.width-video.height - (video.width-video.height)%2;

  for (var y = 0; y < video.height; y++) {

    for (var x = 0; x < video.height; x++) {

      var index = (video.width - (x+0.5*delta) - 1 + (y * video.width)) * 4;

      var r = video.pixels[index + 0];

      var g = video.pixels[index + 1];

      var b = video.pixels[index + 2];

      var bright = (r + g + b) / 3;

      var w = map(((bright/255)**1.1 )* 255, 0, 255, 0, vScale)**1.1;

      noStroke();

      fill(r,g,b);

      rectMode(CENTER);

      rect(x * vScale, y * vScale, w, w);

    }

  }

​

}

​

function hilbert(i) {

  let points = [

    createVector(0, 0),

    createVector(0, 1),

    createVector(1, 1),

    createVector(1, 0),

  ];

​

  let index = i & 3;

  let v = points[index];

​

  for (let j = 1; j < order; j++) {

    i = i >>> 2;

    index = i & 3;

    let len = 2 ** j;

    if (index == 0) {

      let tempx = v.x;

      v.x = v.y;

      v.y = tempx;

    } else if (index == 1) {

      v.y += len;

    } else if (index == 2) {

      v.x += len;

      v.y += len;

    } else if (index == 3) {

      let tempx = len - 1 - v.x;

      v.x = len - 1 - v.y;

      v.y = tempx;

​

      v.x += len;

    }

  }

​

  return v;

}