Function MultiGetUniqueIDFromString

Descent3/multi.cpp:6558–6603

Given a string, returns a unique integer for that string

// Given a string, returns a unique integer for that string
uint32_t MultiGetUniqueIDFromString(char *plainstring) {
  int i, t, len;
  uint32_t ret;
  uint8_t cryptstring[PAGENAME_LEN];
  uint32_t vals[4];

  len = strlen(plainstring);

  if (len < 4) {
    for (i = len; i < 4; i++)
      plainstring[i] = ('g' + i);

    len = 4;
  }

  for (i = 0; i < 4; i++) {
    cryptstring[i] = 0;
    uint8_t backbyte;

    if (i == 0)
      backbyte = 0x9a;
    else
      backbyte = plainstring[i - 1];

    for (t = 0; t < len; t++) {
      uint8_t a = plainstring[t];
      uint8_t b = plainstring[i % (t + 1)];

      a *= a;
      b *= b * b;

      cryptstring[i] += a ^ b ^ (backbyte + t);
    }

    vals[i] = cryptstring[i];
  }

  ret = (vals[0] << 24) | (vals[1] << 16) | (vals[2] << 8) | (vals[3]);

  if (ret == 0) {
    Int3(); // Get Jason, no match at all
    return 0;
  }

  return ret;
}

// Returns the unique id of a given object type/id
uint32_t MultiGetMatchChecksum(int type, int id) {