Revision as of 01:15, 28 June 2008

Archive format used for The Sims 2 and SimCity 4 archive data files.

Format

Most Sims 2 Data is as you probably know stored in various types of archive files that all have the same internal format such as package, cache, etc. This format is proprietary to Maxis and has been used in the SimCity 4, and The Sims Online as well as this one.

Entries may be compressed with QFS compression depending on their entry data.

Overview

This is the general structure of DBPF packages:

Header (96 bytes)
File 1
File 2
...
File n
Index Entry 1 (20 bytes)
Index Entry 2
...
Index Entry n 

Header first, individual files following with no filenames and a small file header area at the beginning of each followed by an index of all the files in the archive.

Header

DWORD

Identifier (DBPF - the type of dat)

DWORD

Version Major (1 in TS2/SC4 Dats)

DWORD

Version Minor (0 in SC4 dats, 1 in most TS2 packages)

12 bytes

Reserved (Users can store DBPF info data here if they want)

DWORD

Date Created in Hex (Unused in Version 1.1)

DWORD

Date Modified in Hex (Unused in Version 1.1)

DWORD

Index Major Version (Always 7 in TS2/SC4 dats)

DWORD

Number of entries in the index

DWORD

Location of first index entry

DWORD

Size of index

DWORD

Number of Hole entries in the Hole Record

DWORD

Location of the Hole Record

DWORD

Size of the Hole Record

DWORD

Index Minor Version (Version 1.1+ in TS2 only)

• 01 - 0
• 02 - 1

32 bytes

Reserved for future use in other versions.

Index Table

There are 2 known formats of indexes in the game. The format version is found in the file header.

Version 7.0

(20 bytes, some DBPF 1.1 entries use this format)

DWORD

Type ID (see InternalFormats)

DWORD

Group ID

DWORD

Instance ID

DWORD

Location of the file in the archive

DOWRD

Size of the file

Version 7.1

(24 bytes)

DWORD

Type ID (see InternalFormats)

DWORD

Group ID

DWORD

Instance ID

DWORD

Second Instance ID

DWORD

Location of the file in the archive

DOWRD

Size of the file

Hole Record

A Hole record contains the location and size of all holes in a DBPF file.

repeating

DWORD

Hole Location

DWORD

Hole size

Holes are created when the game deletes something from a DBPF. The holes themselves are simply junk data of the appropriate length to fill the hole.

File

Bulk of DBPF packages. Each file is either uncompressed or compressed. To check if a file is compressed you first need to read the DIR resource, if it exists. (See the corresponding entry for a description). If no DIR entry exists, then no files within the package are compressed.

Compression

When reading a DBPF file, the first thing you should do is check to see if any chunks inside are compressed. This is done via the DIR resource.

For example code and a description of the mechanics, see DBPF Compression.

Directory Files

These are used for compression lists. See E86B1EEF

Header

Only if the file is compressed

DWORD

Compressed Size of file

WORD

Compression ID (0x10FB) QFS Compression. (See packages for compression information)

3 bytes

Uncompressed Size of file

Body

Raw data of the files. See InternalFormats for a list.

Pseudocode

To read files inside a .package file you need to perform the following steps, in order

• Read the DBPF header
• Read the Index tables
• Check for a DIR record
• Check for the file you want to extract
• Is this file compressed? If so, uncompress it
• Read the file data and process accordingly

For an example PHP class for reading DBPF files, see DBPF/Source Code