Graycode :: for analog stuff!

THIS WAS FUN.

Proved the math teacher wrong.

public class Graycode
{
   public static int normalToGray(int orig)
   {
      int gray = 0;
      for (int n = 0; n < 31; n++)
         gray |= (((orig + (1 << n)) >> (n + 1)) & 1) << n;
      return gray;
   }

   public static int grayToNormal(int gray)
   {
      int parity = 0;
      int norm = 0;
      for (int pos = 31; pos >= 0; pos--)
         norm = (norm << 1) | (parity ^= ((gray >> pos) & 1));
      return norm;
   }

   public static int changedBitInNextGrayCode(int gray)
   {
      for (int i = 0; i < 31; i++)
         if (parity(gray >> i) == 0)
            return i + 1;
      return -1;
   }

   private static int parity(int v)
   {
      int c = 0;
      for (int i = 0; i < 31; i++)
         c ^= (v & (1 << i)) >> i;
      return c;
   }
}