d/17063 #explanation by pavel

function u(t) {

c.width=1920 // clear the canvas
for(i=0;i<9;i++)
x.fillRect(400+i*100+S(t)*300,400,50,200) // draw 50x200 rects

} // 122/140

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    u(t) is called 60 times per second.
    t: Elapsed time in seconds.
    S: Shorthand for Math.sin.
    C: Shorthand for Math.cos.
    T: Shorthand for Math.tan.
    R: Function that generates rgba-strings, usage ex.: R(255, 255, 255, 0.5)
    c: A 1920x1080 canvas.
    x: A 2D context for that canvas.

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pavel

function u(t) {

for(c.width=640,i=8;i--;x.stroke())x.beginPath(r=150*2/3*(i>1)),x.arc(320+r*C(a=Math.PI/3*i+t),180+r*S(a),150*(i?1/3:1),0,7)

Jan 4 2020 9:07 PM UTC

}// 124/140

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d/17063 #explanation

u/pavel

If you take every point on this picture, turn it into z=x+i*y and feed it through (sqrt(3)+z)/(1+sqrt(3)*z) then decode the resulting complex number as (x', y') and put a point there, you will get d/17063.
u/pavel

Of course you can't take infinitely many points so you will get a pixelated version. To get a proper version you need to solve the equation for the new, mapped, circle given the old circle so that you can use x.arc..


      u(t) is called 60 times per second.
      t: elapsed time in seconds.
      c: A 1920x1080 canvas.
      x: A 2D context for that canvas.
      S: Math.sin
      C: Math.cos
      T: Math.tan
      R: Generates rgba-strings, ex.: R(255, 255, 255, 0.5)

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