Simplify reduce motion check

[rbdr/r.bdr.sh] / js / animation.js

diff --git a/js/animation.js b/js/animation.js
index 6a67699cab06435bf3f74b3356b08e9fa902a5ab..23d3ca5a7d5dd80188f61cef5d554ebed0ca1e73 100644 (file)
--- a/js/animation.js
+++ b/js/animation.js
@@ -1,7 +1,9 @@
 (function () {
 
+  if (window.matchMedia('(prefers-reduced-motion: reduce)').matches) return
+
   var K = document.querySelector('canvas'),
-    { random: R, PI, cos: C, sin: S, floor, atan2: A } = Math,
+    { random: R, PI, cos: C, sin: S, atan2: A } = Math,
     id = p => p,
     spn = rad => p => ({
         x: p.x + rad * C(l),
@@ -15,21 +17,22 @@
       a: R() * 2 * PI, c: r(100)
     })),
     H = [sqr, crc, hrt, chs, lch], P = [id, spn(5), spn(15)],
-    draw = H[r(H.length)], pos = P[r(P.length)]
+    draw = H[r(H.length)], pos = P[r(P.length)],
+    Z = 1
 
   function r(x) {
-    return floor(R() * x)
+    return ~~(R() * x)
   }
 
   function sqr(i) {
-    var {x, y} = pos(i)
-    X.fillRect(x, y, z, z)
+    var p = pos(i)
+    X.fillRect(p.x, p.y, z, z)
   }
 
   function crc(i) {
-    var {x, y} = pos(i)
+    var p = pos(i)
     B()
-    X.arc(x, y, z / 2, 0, 2 * PI)
+    X.arc(p.x, p.y, z / 2, 0, 2 * PI)
     F()
   }
 
@@ -83,8 +86,10 @@
     i.c = (i.c + 2) % 101
   }
 
+  canvas.addEventListener('click', () => {Z ? Z=0:(Z=1;frm())})
+
   function frm(t) {
-    requestAnimationFrame(frm)
+    if (Z) requestAnimationFrame(frm)
 
     var dt = t - l