​

// ====================

//      Parameters

// ====================

​

let numRings = 7;

let gap = 50

​

​

​

// ====================

//    My Definitions

// ====================

​

// Global variables

​

let rings = [];

let polySynth;

​

// Notes from E minor pentatonic - notes from pentatonic scales basically

// all sound good together

// See https://pulse.berklee.edu/scales/e-minor-pentatonic-scale.html

let notes = ['D4', 'E4', 'D3', 'B3', 'A3', 'E3', 'E2'];

​

​

// Functions

​

// To make it easier to assign notes, since I can just pass a value between 0 to 127 (inclusive). I used an AI to quickly write some of this.

function midiNumberToNoteName(midiNumber) {

    // Clamp the MIDI number between 0 and 127 (validating input)

    midiNumber = max(0, min(midiNumber, 127));

​

    // Define the note names and their corresponding MIDI numbers

    const noteNames = [

        "A", "A#", "B", "C", "C#", "D", "D#", "E", "F", "F#", "G", "G#"

    ];

​

    // Calculate the note index and octave

    const noteIndex = midiNumber % 12; // Get the index for the note

    const octave = floor(midiNumber / 12) - 1; // Calculate the octave

​

    // Construct the note name

    const noteName = noteNames[noteIndex] + octave;

​

    return noteName;

}

​

​

// Classes

​

class Dot {

  constructor(ringRadius, velocity, colour = 255, startingAngle = 0) {

    this.ringRadius = ringRadius;

    this.velocity = velocity;

    this.colour = color(colour);

    this.angle = startingAngle;

  }

  update() {

    this.angle = (this.angle + this.velocity) % TWO_PI;

  }

  hasCollided() {

    let differenceBefore = abs(sin(this.angle - this.velocity));

    let differenceNow = abs(sin(this.angle));

    let differenceAhead = abs(sin(this.angle + this.velocity));

    // check if the dot is closest to the line

    if (differenceNow < differenceBefore && differenceNow < differenceAhead) { 

      return true;

    } else {

      return false;

    }

  }

  display() {

    fill(this.colour);

    noStroke();

    circle(cos(this.angle) * this.ringRadius, sin(this.angle) * this.ringRadius, 20);

  }

}

​

​

class Ring {

  constructor(radius, velocity, colour = 255, note = 'C4') {

    this.radius = radius;

    this.velocity = velocity;

    this.colour = color(colour);

    this.note = note;

    this.thickness = 5;

    this.dots = []

  }

  addDot(startingAngle = 0, colour = this.colour) {

    this.dots.push(new Dot(this.radius, this.velocity, colour, startingAngle));

  }

  update() {

    for (let dot of this.dots) {

      dot.update()

    }

  }

  display() {

​

    let dotHasCollided = false;

    for (let dot of this.dots) {

      if (dot.hasCollided()) {

        dotHasCollided = true;

      }

    }

    if (dotHasCollided) {

      strokeWeight(25)

      // Play a sound

      userStartAudio();

      console.log(this.note);

      polySynth.play(this.note, 0.5, 0, 1);

    } else {

      strokeWeight(this.thickness);

    }

    stroke(this.colour);

    noFill();

    arc(0, 0, 2*this.radius, 2*this.radius, 0, TWO_PI);

    for (let dot of this.dots) {

      dot.display();

    }

  }

}

​

​

​

// =====================

//   p5.js's Functions

// =====================

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  background(0)

  polySynth = new p5.PolySynth(p5.MonoSynth, numRings*2);

  // Initialise the rings and dots

  for (let i = 0; i < numRings; i++) {

    let radius = gap + (width/2 - 2*gap) * i/(numRings-1);

    let dotVelocity = TWO_PI * (i+1)/(30*getTargetFrameRate());

    colorMode(HSL)

    let ringColour = color(i * 360 / numRings, 100, 80);

    colorMode(RGB)

    let note = notes[i];

    //console.log(note);

    rings.push(new Ring(radius, dotVelocity, ringColour, note));

    rings.at(-1).addDot() //.at(-1) returns the last element of an array

  }

}

​

function draw() {

  translate(width/2, height/2)

  background(0, 8);

  fill(255)

  strokeWeight(1)

  stroke(255)

  circle(0, 0, 10)

  noFill()

  line(-width/2 + gap, 0, width/2 - gap, 0)

  for (let ring of rings) {

    ring.update();

    ring.display();

  }

  // drawingContext.filter = 'blur(1px)';

}

​

// Resize the canvas

function windowResized() {

  resizeCanvas(windowWidth, windowHeight)

}