shorten random function

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

diff --git a/js/animation.js b/js/animation.js
index 074b1df3dd15ec556ac3f2081d7f3dfe1b6b1d67..3f44cd81ac8ce48e63d527da7b4ca22a1eb944ef 100644 (file)
--- a/js/animation.js
+++ b/js/animation.js
@@ -1,30 +1,27 @@
 (function () {
 
-  var canvas = document.querySelector('canvas'),
-      r = Math.random,
-      pi = Math.PI,
-      cos = Math.cos,
-      sin = Math.sin,
-      ctx = canvas.getContext('2d'),
+  var K = document.querySelector('canvas'),
+      { random: R, PI, cos, sin, floor, atan2 } = Math,
+      ctx = K.getContext('2d'),
       fps = 24,
       lst = 0,
       spd = 1,
-      siz = 5 + rnd(10),
-      clr = !!(r() > 0.5),
-      ccl = !!(r() > 0.5),
-      I = Array(rnd(10) + 6).fill(null).map(() => ({
-        x: rnd(64),
-        y: rnd(64),
-        a: r() * 2 * pi,
-        c: Array(3).fill(rnd(256))
+      siz = 5 + r(10),
+      clr = R() > 0.5,
+      ccl = R() > 0.5,
+      I = Array(r(10) + 6).fill(null).map(() => ({
+        x: r(64),
+        y: r(64),
+        a: R() * 2 * PI,
+        c: Array(3).fill(r(256))
       })),
       SHP = [sqr, crc, hrt, chs, lch],
       POS = [id, spn(5), spn(15)],
-      draw = SHP[rnd(SHP.length)],
-      pos = POS[rnd(POS.length)];
+      draw = SHP[r(SHP.length)],
+      pos = POS[r(POS.length)];
 
-  function rnd (x) {
-    return Math.floor(r() * x);
+  function r(x) {
+    return floor(R() * x);
   }
 
   function sqr(i) {
@@ -37,7 +34,7 @@
 
     var p = pos(i);
     ctx.beginPath();
-    ctx.arc(p.x, p.y, siz / 2, 0, 2 * pi);
+    ctx.arc(p.x, p.y, siz / 2, 0, 2 * PI);
     ctx.fill();
   }
 
@@ -47,7 +44,7 @@
     ctx.beginPath();
     ctx.moveTo(p.x, p.y);
     ctx.lineTo(p.x * 10 * cos(i.a), p.y * 10 * sin(i.a));
-    ctx.lineTo(rnd(64), rnd(64));
+    ctx.lineTo(r(64), r(64));
     ctx.fill();
   }
 
@@ -68,12 +65,12 @@
     ctx.fillRect(p.x, p.y, siz, siz);
 
     ctx.beginPath();
-    ctx.arc(p.x + siz / 2, p.y, siz / 2, 0, 2 * pi, false);
+    ctx.arc(p.x + siz / 2, p.y, siz / 2, 0, 2 * PI, false);
     ctx.fill();
     ctx.closePath();
 
     ctx.beginPath();
-    ctx.arc(p.x + siz, p.y + siz / 2, siz / 2, 0, 2 * pi, false);
+    ctx.arc(p.x + siz, p.y + siz / 2, siz / 2, 0, 2 * PI, false);
     ctx.fill();
     ctx.closePath();
   }
@@ -99,11 +96,11 @@
     i.y = i.y + spd * sin(i.a);
 
     if (i.x < 0 || i.x > 64) {
-      i.a = Math.atan2(sin(i.a), -cos(i.a))
+      i.a = atan2(sin(i.a), -cos(i.a))
     }
 
     if (i.y < 0 || i.y > 64) {
-      i.a = Math.atan2(-sin(i.a), cos(i.a))
+      i.a = atan2(-sin(i.a), cos(i.a))
     }
   }