Merge pull request #69 from seIncorp/patch-2

Some changes for more easy to read the code.

Author: dalisoft

src/Easing.js

@@ -15,7 +15,7 @@ const Easing = {
 
   Quadratic: {
     In (k) {
-      return k * k
+      return Math.pow(k, 2)
     },
 
     Out (k) {
@@ -24,7 +24,7 @@ const Easing = {
 
     InOut (k) {
       if ((k *= 2) < 1) {
-        return 0.5 * k * k
+        return 0.5 * Math.pow(k, 2)
       }
 
       return -0.5 * (--k * (k - 2) - 1)
@@ -33,7 +33,7 @@ const Easing = {
 
   Cubic: {
     In (k) {
-      return k * k * k
+      return Math.pow(k, 3)
     },
 
     Out (k) {
@@ -42,7 +42,7 @@ const Easing = {
 
     InOut (k) {
       if ((k *= 2) < 1) {
-        return 0.5 * k * k * k
+        return 0.5 * Math.pow(k, 3)
       }
 
       return 0.5 * ((k -= 2) * k * k + 2)
@@ -51,7 +51,7 @@ const Easing = {
 
   Quartic: {
     In (k) {
-      return k * k * k * k
+      return Math.pow(k, 4)
     },
 
     Out (k) {
@@ -60,7 +60,7 @@ const Easing = {
 
     InOut (k) {
       if ((k *= 2) < 1) {
-        return 0.5 * k * k * k * k
+        return 0.5 * Math.pow(k, 4)
       }
 
       return -0.5 * ((k -= 2) * k * k * k - 2)
@@ -69,7 +69,7 @@ const Easing = {
 
   Quintic: {
     In (k) {
-      return k * k * k * k * k
+      return Math.pow(k, 5)
     },
 
     Out (k) {
@@ -78,7 +78,7 @@ const Easing = {
 
     InOut (k) {
       if ((k *= 2) < 1) {
-        return 0.5 * k * k * k * k * k
+        return 0.5 * Math.pow(k, 5)
       }
 
       return 0.5 * ((k -= 2) * k * k * k * k + 2)
@@ -221,14 +221,16 @@ const Easing = {
     },
 
     Out (k) {
-      if (k < 1 / 2.75) {
-        return 7.5625 * k * k
-      } else if (k < 2 / 2.75) {
-        return 7.5625 * (k -= 1.5 / 2.75) * k + 0.75
-      } else if (k < 2.5 / 2.75) {
-        return 7.5625 * (k -= 2.25 / 2.75) * k + 0.9375
+      let x = 2.75
+      let y = 7.5625
+      if (k < 1 / x) {
+        return y * k * k
+      } else if (k < 2 / x) {
+        return y * (k -= 1.5 / x) * k + 0.75
+      } else if (k < 2.5 / x) {
+        return y * (k -= 2.25 / x) * k + 0.9375
       } else {
-        return 7.5625 * (k -= 2.625 / 2.75) * k + 0.984375
+        return y * (k -= 2.625 / x) * k + 0.984375
       }
     },