wind blowing through grass (2025)

// make source public, Spring 2025

// schien@mail.ncku.edu.tw

​

// Example code for lecture "Adding Dimensions"

// an example from Pearson (2011)

// visualizing the noise as a rotation in animation

// schien@mail.ncku.edu.tw, DPD 2023

​

let xstart, xnoise, ystart, ynoise;

let xstartNoise, ystartNoise;

​

function setup() {

  createCanvas(500, 500);

  xstart = random(10);

  ystart = random(15);

  xstartNoise = random(20);

  ystartNoise = random(20);

}

​

function draw() {

  background(255);

  xstartNoise += 0.01;

  ystartNoise += 0.01;

  xstart += (noise(xstartNoise) * 0.5) - 0.25;

  ystart += (noise(ystartNoise) * 0.5) - 0.25;

  xnoise = xstart;

  ynoise = ystart;

  // loop through all pixels

  for (let y = 0; y <= height; y += 5) {

    ynoise += 0.1;

    xnoise = xstart; // reset the noise at the start of each row

    for (let x = 0; x <= width; x += 5) {

      xnoise += 0.1;

      drawPoint(x, y, noise(xnoise, ynoise)); // the noise function that takes 2 parameters

    }

  }

}

​

function drawPoint(x, y, noiseFactor) {

  push(); // start a new drawing state

  translate(x, y);

  rotate(noiseFactor * radians(360));

  stroke(0, 150);

  line(0, 0, 20, 0);

  pop(); // restore original state

}