Decode UTF-8 bytes

decode-utf8.js

var decode = function decode(bytes) {
  var points = [];

  var i = 0, j = 0;
  while (i < bytes.length) {
    if ((bytes[i] & 0x80) === 0) {
      points.push(bytes[i] & 0x7f);
      i += 1;
    } else if ((bytes[i] & 0xE0) === 0xC0) {
      points.push(((bytes[i] & 0x1F) << 6) + (bytes[i+1] & 0x7f));
      i += 2;
    } else if ((bytes[i] & 0xF0) === 0xE0) {
      points.push(((bytes[i] & 0x1F) << 12) + ((bytes[i+1] & 0x7f) << 6) + (bytes[i+2] & 0x7f));
      i += 3;
    } else if ((bytes[i] & 0xF8) === 0xF0) {
      points.push(((bytes[i] & 0x1F) << 18) + ((bytes[i+1] & 0x7f) << 12) + ((bytes[i+2] & 0x7f) << 6) + (bytes[i+3] & 0x7f));
      i += 4;
    }
  }

  return points;
};