// Patterns worth noting:

// * Key latch for export

// * Perlin noise; noiseSeed

// * Pow bias

// Uses https://github.com/zenozeng/p5.js-svg to export SVG.

​

var bExportSvg = false;

function setup() {

  createCanvas(600, 600, SVG);

  noLoop();

}

​

function draw() {

  background(230);

  if (bExportSvg) clear(); 

  strokeWeight(2);

  stroke(0);

  noFill();

​

  var myBaseStepSize = 5;

  var myHeading = random(TWO_PI);

  var headingBias = 0.6;

  var nIters = 5000;

  var cx = width / 2;

  var cy = height / 2;

  var px = cx;

  var py = cy;

​

  beginShape();

  for (var i = 0; i < nIters; i++) {

    var myStepSize = myBaseStepSize + (noise(i / 20.0 + 10) - 0.5);

​

    var dx = px - cx;

    var dy = py - cy;

    var dh01 = max(0.0001, sqrt(dx * dx + dy * dy) / 250);

    myStepSize *= 1.0 - 0.9 * dh01;

​

    myHeading += radians(20.0 * (noise(i / 10.0) - headingBias));

​

    px += myStepSize * cos(myHeading);

    py += myStepSize * sin(myHeading);

​

    dh01 = pow(dh01, -0.3);

    var qx = cx + dx * dh01;

    var qy = cy + dy * dh01;

    vertex(qx, qy);

  }

  endShape();

  noLoop();

  if (bExportSvg){

    saveSVG("gl_linewalk.svg");

    bExportSvg = false;

  }

}

​

//---------------------------------

function keyPressed() {

  if (key == "s") {

    bExportSvg = true;

    loop();

  }

}

​

//---------------------------------

function mousePressed() {

  noiseSeed(millis());

  loop();

}

​