KaiSpirographFork

// SPIROGRAPH

// this p5 sketch uses simple transformations to create a Spirograph-like effect with interlocking circles (called sines).  

// press the spacebar to switch between tracing and showing the underlying geometry.

//

// your tasks:

// (1) tweak the code to change the simulation so that it draws something you like.

// hint: you can change the underlying system, the way it gets traced when you hit the space bar,

// or both.  try to change *both*.  :)

// (2) use p5.sound or tone.js to make the simulation MAKE SOUND.

// hint: the websites for p5.sound and tone.js have lots of examples.

// try and adapt them.

​

var NUMSINES = 10; // how many of these things can we do at once?

var sines = new Array(NUMSINES); // an array to hold all the current angles

var oscs = new Array(NUMSINES);

var rad; // an initial radius value for the central sine

var i; // a counter variable

// play with these to get a sense of what's going on:

var fund = 0.02; // the speed of the central sine

var ratio = 2; // what multiplier for speed is each additional sine?

var alpha = 50; // how opaque is the tracing system

var trace = false; // are we tracing?

​

function setup()

{

  createCanvas(windowWidth, windowHeight);

  rad = height/2; // compute radius for central circle

  background(0); // clear the screen

​

  for (i = 0; i<sines.length; i++)

  {

    sines[i] = PI; // start EVERYBODY facing NORTH

    oscs[i] = new p5.Oscillator('sine');

    oscs[i].amp(0.5);

    oscs[i].freq(50*(i+1));

    oscs[i].start();

  }

}

​

function draw()

{

  if (!trace) {

    background(0); // clear screen if showing geometry

    stroke(random(255), random(255), random(255), random(80, 200));

    strokeWeight(20);

    fill(random(255), random(255), random(255), 80);

  } 

​

  // MAIN ACTION

  push(); // start a transformation matrix

  translate(width/2, height/2); // move to middle of screen

  for (i = 0; i<sines.length; i++) // go through all the sines

  {

    var erad = 0; // radius for small "point" within circle... this is the 'pen' when tracing

    // setup for tracing

    if (trace) {

      stroke(random(255), random(255), 255*(float(i)/sines.length), 80); // choose color

      fill(255, 255, 255, alpha/2); 

      erad = 1.5*(1.0-float(i)/sines.length); // pen width will be related to which sine

    }

    var radius = rad/(i+1); // radius for circle itself

    rotate(sines[i/2]); // rotate circle

    if (!trace) ellipse(0, 0, radius/2, radius/2); // if we're simulating, draw the sine

     push(); // go up one level

    translate(0, radius/2); // move to sine edge

    if (!trace){

      ellipse(radius, 0, 3, 3); // draw a little circle

      ellipse(radius, 0, 6, 6);

      ellipse(radius, 0, 9, 9);

    }

    if (trace){

      ellipse(0, 0, erad, erad); // draw with erad if tracing

      ellipse(0, 0, erad, erad);

      ellipse(0, 0, erad, erad);

    }

      pop(); // go down one level

      translate(0, radius/3); // move into position for next sine

      oscs[i].amp((sines[i]/TWO_PI), 0.05);

      sines[i] = (sines[i]+(fund+(fund*i*ratio)))%TWO_PI; // update angle based on fundamental

  }

  pop(); // pop down final transformation

}

​

function keyReleased()

{

  if (key==' ') {

    trace = !trace; 

    background(0);

  }

}