Difference between revisions of "Sims 3:DBPF"

Revision as of 18:16, 2 June 2009

Package Header - 96 bytes: "standard" DBPF 2.0 format; DBBF not seen.

Code:
DWORD    magic ;; "DBPF"
DWORD    major ;; 2
DWORD    minor ;; 0
BYTE[24] unknown1
DWORD    ;; number of index entries - if zero, size and position also zero
BYTE[4]  unknown2
DWORD    ;; size of index on disk in bytes
BYTE[12] unknown3
DWORD    ;; is always 0x00000003 ?
DWORD    ;; position of index (absolute)
BYTE[28] unknown4
There are a number of different index formats.  The Spore ones are newer than the Sims3 ones, we think, as they use an extra type bit - and the DBBF files!

If position is not zero, at that position:
DWORD ;; Index type

The count of set bits in the index type is the number of additional DWORD entries in index header:
DWORD[(for each bit in Index type)]

The number of DWORDs in an actual index entry is 8.  The entry is stored in two parts - the index header and then the entry on disk.  The header provides the data that is constant to all entries, essentially a kind of compression.

;; For each index entry on disk:
DWORD[(8 - number of bits in Index type)]

Each DWORD in an actual index entry can either come from the header or from the index entry on disk, depending on the bits set in the index type.  The order of the DWORDs in an index entry is (with matching bit number):
0 - ResourceType
1 - ResourceGroup
2 - InstanceHi
3 - InstanceLo
4 - Chunkoffset ;; Absolute location in package
5 - Filesize ;; Length of data in package
6 - Memsize ;; Length of uncompressed data
7 - Compressed(lo WORD) | Unknown2(hi WORD) ;; Compressed is 0x0000 or 0xFFFF
(That's a total of 32 bytes per entry.)

(Possibly confusingly, in my implementation, I actually store the index type along with the entries - keeps the data structure simpler..!)

By Peter Jones