code: function curvePrecision(index, dim) { // :: Int -> Int -> Int
      /*
      dim         index       xyz axis    m       bits
      1            0-7        0<=x<2      2       3
      2           0-63        2<=x<4      3       6
      3           0-511       4<=x<8      4       9
      4           4095        8<=x<16     5       12
      5           32767       16<=x<32    6       15
      6         262,144       32<=x<64    7       18
      7       2,097,151       64<=x<128   8       21
      8       16,777,215      128<=x<256  9       24
      9       134,217,727     254<=x<512  10      27
      10      1,073,741,823   512<=x<1024 11      30
      */
  
      var n = Math.pow(2, dim)
      var bits = 32
  
      while(bits % dim != 0) --bits
  
      for (var i=1; i < bits; i++) {
          if (index < Math.pow(n, i)) return i+1
      }
  }
docs: curve precision