Help with converting code

[Tech]

Hello.

I need some help with converting this code to VB.

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int GamePacketDecode(unsigned char *indata, unsigned int insize,
                   unsigned char *outdata, unsigned int outmax,
                   unsigned int *outsize)
{
  unsigned int a, b, c, d;
  unsigned int maxcnt, index, cnt;
  unsigned char *outptr, *inptr;
  int size;

  b = 0;

  size = insize;
  inptr = indata;

  maxcnt = outmax;
  outptr = outdata;
  cnt = 0x20;

  while (1) {

      if (cnt >= 0x8) {
          while (size > 0 && cnt >= 8) {
              cnt -= 0x8;
              size--;
              a = *inptr++ << cnt;
              b |= a;
          };
      }

      index = CharIndex[b >> 0x18];
      a = CharTable[index];
      d = (b >> (0x18 - a)) & BitMasks[a];
      c = CharTable[index + 2*d + 2];

      cnt += c;
      if (cnt > 0x20) {
          *outsize = outmax - maxcnt;
          return 1;
      }

      if (maxcnt-- == 0)
          return 0;

      a = CharTable[index + 2*d + 1];
      *outptr++ = (unsigned char)a;

      b <<= (c & 0xFF);
  }

  assert(0);
  return 0;
}


So far I have converted everything but  these 2 lines

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a = *inptr++ << cnt;


Code Select Expand


*outptr++ = (unsigned char)a;


I took a guess, but no luck..heres my code

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Dim lInptr As Long

        lInptr = Len(Inptr)
        lInptr = lInptr + 1

        A = LeftShift(lInptr, CNT)

and..

Outptr = A



Any help would be greatly appreciated.

p.s: for those who don't know..this code decompress a d2gs packet into data.
It was found here: http://forum.valhallalegends.com/phpbbs/index.php?topic=585.0

[Ringo]

MyndFyre explained alot of that here
I persionaly wouldnt bother porting the tables to VB6, as its fairly slow.

[Yegg]

a = *inptr++ << cnt;

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Dim tmp_inptr As Integer
tmp_inptr= inptr + 1
a = LeftShift(tmp_inptr, cnt)

*outptr++ = (unsigned char)a;

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Dim tmp_outptr As String
tmp_outptr = outptr + 1
tmp_outptr = a ' Convert a to a string (character) (Havn't used VB in a while, I forgot how to do that