DDI Wad

DDI Wad

Filename extensions	.wad, .pwp
Magic number	WADH, WWAD PWP: PWAD, PSWD
Developed by	Data Design Interactive
Initial release	1997
Type of format	Archive file
Container for	Video game files

DDI Wad is an archive file format developed by Data Design Interactive for storing files in video games. DDI Wad files usually use the file extension .wad.

The DDI Wad format is unrelated to Doom WAD or Wii WAD files.

File formats

Original Wad

This section is for the WAD files used in Conquest Earth. Unlike later formats, these Wads store file information after file data.

File structure

Type	Value	Description
char[4]	"ROOT"	ASCII file signature?

WWAD

This section is for the WAD files used in LEGO Rock Raiders and Gubble Buggy Racers.

File structure

Type	Value	Description
char[4]	"WWAD"	ASCII file signature. Always 57 57 41 44 (WWAD).
uint32	Count	Number of file entries in the WAD file. Example: D6 00 00 00 for a WAD containing 214 files.
cstring[]	Names	Relative file paths and names within the WAD file ("Relative directories" or "Reldirs"). Each path is followed by a null character before the next entry. Example: Languages\ObjectiveText.txt
cstring[]	BuildNames	Original file paths used when building the WAD file for each file listed in Names, following the same order ("Absolute directories" or "Absdirs"). Each path is followed by a null character before the next entry. Example: \\ROBW\C\Dev\SourceSafe\Lego\Languages\0009-English\Data\Languages\ObjectiveText.txt
Entry[]	Entries	Storage metadata for each file listed in Names, following the same order. Each entry is 16 bytes and lists a file's storage format, file size, and location in the WAD. See the table below for more details.
byte[]	Data	File data

Entry structure

Type	Value	Description
uint32	Flags	Flag determining the file's storage format. This entry is thought to be read as a single byte, though its entry still takes up 4 bytes of space. The flag has two known options: 01 for Store (uncompressed), 02 for Rob Northern compression (RNC). The game engine does not check for the Store flag, rather it checks against the RNC flag. By default, no versions of LEGO Rock Raiders or Gubble Buggy Racer are known to use RNC; it is, however, used in Conquest Earth. For more information on RNC, see Sega Retro and ModdingWiki.
uint32	PackedSize	Packed size of the file's data in the WAD file. If the file is flagged as uncompressed, this entry must be identical to UnpackedSize.
uint32	UnpackedSize	Original unpacked size of the file's data.
uint32	Offset	Absolute offset to the file's data in the WAD, counting the number of bytes from the start of the WAD to the start of the file's data.

WADH

This section is for the WAD files first used in Tonka Space Station. This format seems to have remained mostly unchanged through My Personal Golf Trainer in 2010.

File structure

Type	Value	Description
char[4]	"WADH"	ASCII file signature. Always 57 41 44 48 (WADH).
uint32	Offset	Absolute offset to the file data section of the WAD.
uint32	Count	Number of file and folder entries in the WAD file.
uint32	Offset	Either the length of the Names block or the offset of file data after it?
Entry[]	Entries	Storage metadata for each file and folder

Usage

LEGO Rock Raiders uses two WAD files by default. These files are located in the game's install directory along with its executable file. LegoRR0.wad stores the majority of the game's data, while LegoRR1.wad stores the Main Lego Config File and language-related files. Additional streamed files are also stored in the Data folder, while streamed FMV files are stored in a separate Data folder on the game's disc.

LEGO Rock Raiders WAD file names are determined by the name of the game's executable file. When loading, LEGO Rock Raiders looks for WAD files sharing a name with the game's executable, following the format of <exename>#.wad. As the game's executable is named LegoRR.exe by default, the game looks for WAD files named LegoRR#.wad (the same functionality is used with the Lego* {} and LegoRR {} sections in its configuration-format files).

The game searches for up to ten WAD files while loading, LegoRR0.wad to LegoRR9.wad. The WAD files do not have to have sequential numbers. The contents of WAD files with higher numbers take precedence over those with lower numbers (so if a file with the same name and path is stored in LegoRR0 and LegoRR1, only the file in LegoRR1 will be loaded).