TPWS, INTS, LAYS

What is TPWS / INTS / LAYS?

TPWS (Theme Park World Save) is the main save format used within Theme Park World, alongside INTS (Initial Save?) and LAYS (Online-related save file, usually named "upload.LAYS"). This file is used to store game progress and likely contains, among other things, a serialized copy of all objects, entities, etc. within a single game level. This file is read from when the level starts in order to carry progress between game sessions.

File format

Header

• 4 bytes: Magic number - F4 01 00 00
• Copyright notice - 0x0004 to 0x033B
• Padding - 0x033C to 0x0603

File info

• 4 bytes: File type (00 01 22 19)
• 1 byte: File version (85)
• 1 byte: Online flag (00 = offline save, 01 = upload.LAYS)
• 2 bytes: Padding

If online flag set:

• Unknown data - 0x060C to 0x0846

Data

ZLIB Header:

• 4 bytes: Magic number - BILZ
• 4 bytes: Unknown
• 4 bytes: Compressed length
• 16 bytes: Unknown
• ZLIB stream begins after this point, continues to end of file