image/lib/src/formats/pvrtc/pvrtc_bit_utility.dart

class BitUtility {
  static bool isPowerOf2(int x) => (x & (x - 1)) == 0;

  static int rotateRight(int value, int shift) =>
      (value >> shift) | (value << (32 - shift));

  static const List<int> BITSCALE_5_TO_8 = const [
   0, 8, 16, 24, 32, 41, 49, 57, 65, 74,
   82, 90, 98, 106, 115, 123, 131, 139, 148, 156,
   164, 172, 180, 189, 197, 205, 213, 222, 230, 238,
   246, 255];

  static const List<int> BITSCALE_4_TO_8 = const [
   0, 17, 34, 51, 68, 85, 102, 119, 136, 153,
   170, 187, 204, 221, 238, 255];

  static const List<int> BITSCALE_3_TO_8 = const [
   0, 36, 72, 109, 145, 182, 218, 255];

  static const List<int> BITSCALE_8_TO_5_FLOOR = const [
   0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
   1, 1, 1, 1, 1, 1, 1, 2, 2, 2,
   2, 2, 2, 2, 2, 3, 3, 3, 3, 3,
   3, 3, 3, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 5, 5, 5, 5, 5, 5, 5, 5,
   6, 6, 6, 6, 6, 6, 6, 6, 7, 7,
   7, 7, 7, 7, 7, 7, 8, 8, 8, 8,
   8, 8, 8, 8, 8, 9, 9, 9, 9, 9,
   9, 9, 9, 10, 10, 10, 10, 10, 10, 10,
   10, 11, 11, 11, 11, 11, 11, 11, 11, 12,
   12, 12, 12, 12, 12, 12, 12, 13, 13, 13,
   13, 13, 13, 13, 13, 13, 14, 14, 14, 14,
   14, 14, 14, 14, 15, 15, 15, 15, 15, 15,
   15, 15, 16, 16, 16, 16, 16, 16, 16, 16,
   17, 17, 17, 17, 17, 17, 17, 17, 17, 18,
   18, 18, 18, 18, 18, 18, 18, 19, 19, 19,
   19, 19, 19, 19, 19, 20, 20, 20, 20, 20,
   20, 20, 20, 21, 21, 21, 21, 21, 21, 21,
   21, 22, 22, 22, 22, 22, 22, 22, 22, 22,
   23, 23, 23, 23, 23, 23, 23, 23, 24, 24,
   24, 24, 24, 24, 24, 24, 25, 25, 25, 25,
   25, 25, 25, 25, 26, 26, 26, 26, 26, 26,
   26, 26, 26, 27, 27, 27, 27, 27, 27, 27,
   27, 28, 28, 28, 28, 28, 28, 28, 28, 29,
   29, 29, 29, 29, 29, 29, 29, 30, 30, 30,
   30, 30, 30, 30, 30, 31];

  static const List<int> BITSCALE_8_TO_4_FLOOR = const [
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   0, 0, 0, 0, 0, 0, 0, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
   7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
   7, 7, 7, 7, 7, 7, 8, 8, 8, 8,
   8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
   8, 8, 8, 9, 9, 9, 9, 9, 9, 9,
   9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
   10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
   10, 10, 10, 10, 10, 10, 10, 11, 11, 11,
   11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
   11, 11, 11, 11, 12, 12, 12, 12, 12, 12,
   12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
   12, 13, 13, 13, 13, 13, 13, 13, 13, 13,
   13, 13, 13, 13, 13, 13, 13, 13, 14, 14,
   14, 14, 14, 14, 14, 14, 14, 14, 14, 14,
   14, 14, 14, 14, 14, 15];

  static const List<int> BITSCALE_8_TO_3_FLOOR = const [
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   0, 0, 0, 0, 0, 0, 0, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 7];

  static const List<int> BITSCALE_8_TO_5_CEIL = const [
   0, 1, 1, 1, 1, 1, 1, 1, 1, 2,
   2, 2, 2, 2, 2, 2, 2, 3, 3, 3,
   3, 3, 3, 3, 3, 4, 4, 4, 4, 4,
   4, 4, 4, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 6, 6, 6, 6, 6, 6, 6, 6,
   7, 7, 7, 7, 7, 7, 7, 7, 8, 8,
   8, 8, 8, 8, 8, 8, 9, 9, 9, 9,
   9, 9, 9, 9, 9, 10, 10, 10, 10, 10,
   10, 10, 10, 11, 11, 11, 11, 11, 11, 11,
   11, 12, 12, 12, 12, 12, 12, 12, 12, 13,
   13, 13, 13, 13, 13, 13, 13, 14, 14, 14,
   14, 14, 14, 14, 14, 14, 15, 15, 15, 15,
   15, 15, 15, 15, 16, 16, 16, 16, 16, 16,
   16, 16, 17, 17, 17, 17, 17, 17, 17, 17,
   18, 18, 18, 18, 18, 18, 18, 18, 18, 19,
   19, 19, 19, 19, 19, 19, 19, 20, 20, 20,
   20, 20, 20, 20, 20, 21, 21, 21, 21, 21,
   21, 21, 21, 22, 22, 22, 22, 22, 22, 22,
   22, 23, 23, 23, 23, 23, 23, 23, 23, 23,
   24, 24, 24, 24, 24, 24, 24, 24, 25, 25,
   25, 25, 25, 25, 25, 25, 26, 26, 26, 26,
   26, 26, 26, 26, 27, 27, 27, 27, 27, 27,
   27, 27, 27, 28, 28, 28, 28, 28, 28, 28,
   28, 29, 29, 29, 29, 29, 29, 29, 29, 30,
   30, 30, 30, 30, 30, 30, 30, 31, 31, 31,
   31, 31, 31, 31, 31, 31];

  static const List<int> BITSCALE_8_TO_4_CEIL = const [
   0, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 7, 7, 7, 7, 7, 7, 7,
   7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
   8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
   8, 8, 8, 8, 8, 8, 8, 9, 9, 9,
   9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
   9, 9, 9, 9, 10, 10, 10, 10, 10, 10,
   10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
   10, 11, 11, 11, 11, 11, 11, 11, 11, 11,
   11, 11, 11, 11, 11, 11, 11, 11, 12, 12,
   12, 12, 12, 12, 12, 12, 12, 12, 12, 12,
   12, 12, 12, 12, 12, 13, 13, 13, 13, 13,
   13, 13, 13, 13, 13, 13, 13, 13, 13, 13,
   13, 13, 14, 14, 14, 14, 14, 14, 14, 14,
   14, 14, 14, 14, 14, 14, 14, 14, 14, 15,
   15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
   15, 15, 15, 15, 15, 15];

  static const List<int> BITSCALE_8_TO_3_CEIL = const [
   0, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
   1, 1, 1, 1, 1, 1, 1, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
   2, 2, 2, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
   4, 4, 4, 4, 4, 4, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
   5, 5, 5, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
   6, 6, 6, 6, 6, 6, 6, 6, 6, 7,
   7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
   7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
   7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
   7, 7, 7, 7, 7, 7];
}