Rewrite base64 helpers using atob/btoa.

src/base64.js

@@ -1,51 +1,9 @@
-const lookup = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
-
-// TODO: use btoa()/atob() to simplify.
-
-export function encodeArray(arr) {
-  var t = '';
-  for (let i = 0; i < arr.length; i += 3) {
-    var c0 = arr[i + 0];
-    var c1 = arr[i + 1];
-    var c2 = arr[i + 2];
-
-    // aaaaaabb bbbbcccc ccdddddd
-    var a = c0 >>> 2;
-    var b = ((c0 & 3) << 4) | (c1 >>> 4);
-    var c = ((c1 & 15) << 2) | (c2 >>> 6);
-    var d = c2 & 63;
-
-    if (i + 1 >= arr.length) {
-      c = 64;
-    }
-    if (i + 2 >= arr.length) {
-      d = 64;
-    }
-
-    t += lookup.charAt(a) + lookup.charAt(b) + lookup.charAt(c) + lookup.charAt(d);
-  }
-  return t;
+export function encodeArray(bytes) {
+  const binString = String.fromCodePoint(...bytes);
+  return btoa(binString);
 }
 
-export function decodeArray(str, arr) {
-  var outi = 0;
-
-  for (let i = 0; i < str.length; i += 4) {
-    var a = lookup.indexOf(str.charAt(i + 0));
-    var b = lookup.indexOf(str.charAt(i + 1));
-    var c = lookup.indexOf(str.charAt(i + 2));
-    var d = lookup.indexOf(str.charAt(i + 3));
-
-    var c0 = (a << 2) | (b >>> 4);
-    var c1 = ((b & 15) << 4) | (c >>> 2);
-    var c2 = ((c & 3) << 6) | d;
-
-    arr[outi++] = c0;
-    if (c !== 64) {
-      arr[outi++] = c1;
-    }
-    if (d !== 64) {
-      arr[outi++] = c2;
-    }
-  }
+export function decodeArray(base64) {
+  const binString = atob(base64);
+  return Uint8Array.from(binString, m => m.codePointAt(0));
 }

src/hardware.js

@@ -37,7 +37,10 @@ class Mempack {
     }
     // Restore from local storage if provided.
     if (item && item.data) {
-      base64.decodeArray(item.data, this.data);
+      const arr = base64.decodeArray(item.data);
+      for (let i = 0; i < arr.length && i < this.data.length; i++) {
+        this.data[i] = arr[i];
+      }
     }
   }
 }
@@ -215,7 +218,10 @@ export class Hardware {
       const memory = new MemoryRegion(new ArrayBuffer(saveSize));
       const saveItem = n64js.getLocalStorageItem('save');
       if (saveItem && saveItem.data) {
-        base64.decodeArray(saveItem.data, memory.u8);
+        const arr = base64.decodeArray(saveItem.data);
+        for (let i = 0; i < arr.length && i < memory.u8.length; i++) {
+          memory.u8[i] = arr[i];
+        }
       }
       this.saveMem = memory;
     } else {