//  

// Draws three sin waves with varying 

// amplitudes and wavelengths. 

// Adapted from Processing handbook.

​

function setup() {

  createCanvas(400, 100);

  background(220);

  noStroke();

  fill(0);

  // We can substitute variables for the fixed numbers in

  // the previous example to change the shape of the wave.

  drawWave(PI / 10, 35);

  fill(100);

  drawWave(PI / 20, 25);

  fill(255);

  drawWave(PI / 40, 10);

}

​

// Draws a wave across the screen

function drawWave(angleInc, scaleVal){

  let angle = 0;

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

    let y = 50 + (sin(angle) * scaleVal);

    rect(x, y, 2, 4);

    angle += angleInc;

  }

}