Difference between revisions of "Sims 3:DBPF"
m |
m |
||
| Line 65: | Line 65: | ||
(Possibly confusingly, in my implementation, I actually store the index type along with the entries - keeps the data structure simpler..!) | (Possibly confusingly, in my implementation, I actually store the index type along with the entries - keeps the data structure simpler..!) | ||
| − | + | ==Chunk Compression== | |
| + | TBC | ||
<hr/> | <hr/> | ||
<br/>Above documented by Peter Jones | <br/>Above documented by Peter Jones | ||
Revision as of 23:23, 20 June 2009
Package Header
96 bytes: "standard" DBPF 2.0 format; DBBF not seen; DBPP is encrypted.
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 index_version ;; always 3 DWORD ;; position of index (absolute) BYTE[28] unknown4
The Index
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 (lo 31bits) , Unknown1 (hi bit) | 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..!)
Chunk Compression
TBC
Above documented by Peter Jones
Based on Spore package format
