Asobo Save Game File Format Specification

This is the save game format used in FUEL. Other games have different formats. Saves are located in %USERPROFILE%\Documents\My Games\FUEL this directory contains one subdirectory for each GFWL profile name, where the name of the subdirectory is the same as the name of the profile. Each of these subdirectories contains a single FUEL_SAVE_V14.sav file which is the save game for that profile. Note that save games use the Alternate CRC-32 algorithm and not the primary one.

struct SaveGame
{
    std::uint32_t xliveHeaderSize;
        // Always 4
        // Written by xlive
    std::uint32_t saveGameDataCRC32Checksum0;
        // Alternate CRC-32 Checksum of saveGameData taken as a raw byte buffer
        // Equals saveGameDataCRC32Checksum1
        // Written by xlive
    SaveGameData saveGameData;
        // 199996 bytes
    std::uint32_t saveGameDataCRC32Checksum1;
        // Alternate CRC-32 Checksum of saveGameData taken as a raw byte buffer
        // Equals saveGameDataCRC32Checksum0
};

struct SaveGameData 
{
    std::uint32_t dataCompressedSize;
        // Includes the sizes of dataCompressedSize and dataDecompressedSize
    std::uint32_t dataDecompressedSize;
    std::uint8_t data[dataCompressedSize - 4 - 4];
        // dataCompressedSize and dataDecompressedSize are part of the compressed data so we subtract their size from the data array
        // Data is compressed using Order 1 Arithmetic Coding
        // RTTI indicates that the implementation is a modification of the one presented at the end of
        // https://www.researchgate.net/publication/236980434_Arithmetic_Coding_revealed_-_A_guided_tour_from_theory_to_praxis#pf2f
    std::uint8_t zeros[199996 - dataCompressedSize - 1];
        // Filled with 0x00
        // Used to pad the SaveGameData structure size to 199996 bytes
    std::uint8_t version;
        // Always equals 61
};