let theta, phi

let ls

let c1px, c2py

​

function setup() {

    createCanvas(600, 600)

    cent1 = createVector(200, 400, 100) // x, y, r

    cent2 = createVector(450, 100, 70) // x, y, r

​

    ls = createGraphics(600, 600)

​

    theta = 0

    phi = 0

​

    stroke("#fff")

    strokeWeight(3)

    c1px = cent1.x + cent1.z * cos(theta)

    c2py = cent2.y + cent2.z * sin(phi + PI / 3)

}

​

function draw() {

    background("#000")

​

    let c1x = cent1.x + cent1.z * cos(theta)

    let c1y = cent1.y + cent1.z * sin(theta)

    let c2x = cent2.x + cent2.z * cos(phi + PI / 3)

    let c2y = cent2.y + cent2.z * sin(phi + PI / 3)

​

    point(c1x, c1y)

    point(c2x, c2y)

    drawCircle(cent1.x, cent1.y, cent1.z)

    drawCircle(cent2.x, cent2.y, cent2.z)

​

    push()

    stroke(255, 0, 0, 100)

    line(c1x, c1y, c1x, c2y)

    line(c2x, c2y, c1x, c2y)

​

    point(c1x, c2y)

    ls.stroke(255, 0, 0, 200)

    ls.line(c1px, c2py, c1x, c2y)

    pop()

​

    image(ls, 0, 0)

​

    theta += 0.02

    phi += 0.01

    c1px = c1x

    c2py = c2y

​

    if (theta >= TAU) theta -= TAU

    if (phi >= TAU) theta -= TAU

}

​

function drawCircle(x, y, r) {

    push()

    noFill()

    strokeWeight(1)

    stroke(255, 200)

    circle(x, y, 2 * r)

    pop()

}

​