// James Arthur

//

// Fourier Series

// Daniel Shiffman

// https://thecodingtrain.com/CodingChallenges/125-fourier-series.html

// https://youtu.be/Mm2eYfj0SgA

​

let time = 0;

let wave = [];

let path = [];

let k = 2;

​

function setup() {

    createCanvas(600, 400);

}

​

function draw() {

    background(0);

    translate(150, 200);

​

    let x = 0;

    let y = 0;

​

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

        let prevx = x;

        let prevy = y;

​

        let n = i * 2 + 1;

        let radius = 75 * (4 / (n * PI));

        x += radius * cos(n * time);

        y += radius * sin(n * time);

​

        stroke(255, 100);

        noFill();

        ellipse(prevx, prevy, radius * 2);

​

        //fill(255);

        stroke(255);

        line(prevx, prevy, x, y);

        //ellipse(x, y, 8);

    }

    wave.unshift(y);

​

​

    translate(200, 0);

    line(x - 200, y, 0, wave[0]);

    beginShape();

    noFill();

    for (let i = 0; i < wave.length; i++) {

        vertex(i, wave[i]);

    }

    endShape();

​

    time += 0.05;

​

​

    if (wave.length > 250) {

        wave.pop();

        k = k + 0.01;

    }

}