RAC file

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Revision as of 06:49, 27 August 2010 by Strangerke (talk | contribs) (Fascination TODO- Add first elements of RAC file structure)
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The RAC file is the file used by Coktel for the protection in Fascination CD (deleted TOC). it contains, for all the missing file, their name, address and size (between others).

The structure of the file is the folowing:

Header: 18 bytes, contains a version, arraysize1 and arraysize2

Body:

  • Unknown array: arraysize1 * 14 bytes (unused for Fascination)
  • Missing file array : arraysize2 * 30 bytes

The encryption of the missing file array is a simple XOR.

  for (int i = 0; i < (arraysize2 * 30); i++)
     missingFileArray[i] ^= (i * i);

The structure of this array is then, for each 30 bytes in it:

  • 14 bytes: filename
  • 10 bytes: unknown (containing the offset on the CDROM ?)
  • 4 bytes : size
  • 2 bytes : unknown

It's interesting to notice that, in this RAC file,

  • Coktel used 'intro.stk' name instead of 'disk0.stk' in the other versions
  • the track audio is present and named 'FASCI1N.SON'. Of course, We don't need this file.