git.r.bdr.sh - rbdr/r.bdr.sh/blob - js/animation.js

   1 (function () {
   2
   3   if (window.matchMedia('(prefers-reduced-motion: reduce)').matches) return
   4
   5   var K = document.querySelector('canvas'),
   6     { random: R, PI, cos: C, sin: S, atan2: A } = Math,
   7     id = p => p,
   8     spn = rad => p => ({
   9         x: p.x + rad * C(l),
  10         y: p.y + rad * S(l)
  11     }),
  12     X = K.getContext('2d'), F = X.fill.bind(X), B = X.beginPath.bind(X),
  13     f = 24, l = 0, s = 1, z = 5 + r(10),
  14     k = R() > 0.5, c = R() > 0.5,
  15     I = Array(r(10) + 6).fill().map(() => ({
  16       x: r(64), y: r(64),
  17       a: R() * 2 * PI, c: r(100)
  18     })),
  19     H = [sqr, crc, hrt, chs, lch], P = [id, spn(5), spn(15)],
  20     draw = H[r(H.length)], pos = P[r(P.length)],
  21     Z = 1
  22
  23   function r(x) {
  24     return ~~(R() * x)
  25   }
  26
  27   function sqr(i) {
  28     var p = pos(i)
  29     X.fillRect(p.x, p.y, z, z)
  30   }
  31
  32   function crc(i) {
  33     var p = pos(i)
  34     B()
  35     X.arc(p.x, p.y, z / 2, 0, 2 * PI)
  36     F()
  37   }
  38
  39   function chs(i) {
  40     var {x, y} = pos(i)
  41     B()
  42     X.moveTo(x, y)
  43     X.lineTo(x * 10 * C(i.a), y * 10 * S(i.a))
  44     X.lineTo(r(64), r(64))
  45     F()
  46   }
  47
  48   function lch(i) {
  49     var {x, y} = pos(i)
  50     B()
  51     X.lineWidth = 5
  52     X.strokeStyle = `hsl(0,0%,${i.c}%)`
  53     X.moveTo(x, y)
  54     X.lineTo(x * 10 * C(i.a), y * 10 * S(i.a))
  55     X.stroke()
  56   }
  57
  58   function hrt(i) {
  59     var {x, y} = pos(i)
  60     X.fillRect(x, y, z, z)
  61
  62     B()
  63     X.arc(x + z / 2, y, z / 2, 0, 2 * PI, false)
  64     F()
  65     X.closePath()
  66
  67     B()
  68     X.arc(x + z, y + z / 2, z / 2, 0, 2 * PI, false)
  69     F()
  70     X.closePath()
  71   }
  72
  73   function mov(i) {
  74     i.x = i.x + s * C(i.a)
  75     i.y = i.y + s * S(i.a)
  76
  77     if (i.x < 0 || i.x > 64) {
  78       i.a = A(S(i.a), -C(i.a))
  79     }
  80     if (i.y < 0 || i.y > 64) {
  81       i.a = A(-S(i.a), C(i.a))
  82     }
  83   }
  84
  85   function ucl(i) {
  86     i.c = (i.c + 2) % 101
  87   }
  88
  89   function frm(t) {
  90     if (Z) requestAnimationFrame(frm)
  91
  92     var dt = t - l
  93
  94     if (dt > 1000 / f) {
  95       k && X.clearRect(0, 0, 64, 64)
  96       for (var i of I) {
  97         X.fillStyle = `hsl(0,0%,${i.c}%)`
  98         draw(i)
  99         c && ucl(i)
 100         mov(i)
 101       }
 102
 103       l = t
 104     }
 105   }
 106
 107   K.addEventListener('click', () => (Z = Z ? 0:(frm(),1)))
 108   frm()
 109 }
 110 )()