A small dll that allows the Trails in the Sky games to load files from directories instead of archive files. It's more convenient that way. This is meant both to simplify development of mods by cutting out the repacking step from the edit cycle, and also as a way of distributing mods, reducing file sizes and reducing file conflicts by shipping files instead of entire archives.
To install, download
d3dxof.dll and
place it in the game's main data directory (next to ed6_win*.exe).
Most of the games' data is packed into a number of archive files, named
ED6_DT00 through ED6_DT3F. It is not known exactly why these archives are
used, but possibly it improves performance since the operating system knows
that those files are frequently used and keeps them close at hand.
Each archive consists of two files: ED6_DTnn.dir and ED6_DTnn.dat. The
.dir file lists which files exist in the archive, with filename, location in
the .dat file, and some metadata. The .dat file, correspondingly, holds the
contents of all the files.
Most files in the archives are compressed. There is no real way to tell just
from the files whether they are compressed: the games instead determines this
based on what context they are used in. I believe .wav and ._ds (DDS) files
are uncompressed while everything else is compressed, but I am not certain
about this.
Files inside the archives are referenced in two different ways: by filename, or by file id. Just like with compression, which method is used in each situation seems largely arbitrary.
Filename lookups always happen in a specific archive1 (for
example, ._da files, containing fonts, are always in ED6_DT20). The list of
files is simply scanned linearly, and the first entry with a matching name is
used.
File ids consist of a pair of numbers, denoting which archive the file is
in, and an ordinal inside this archive, as listed in the .dir file. In this
method, the filename is ignored. However, they can be assigned freely to any
archive, unlike filenames, which as mentioned are only looked for in a single
archive.
Some ED6_DTnn.dat files have no corresponding .dir file. These are in fact
not archive files at all — they are video files, which can be played with just
about any video player.
Internally, filenames are stored in the archives as uppercase 8.3 strings,
like T0310 ._DT. However, a multitude of factors2 indicate that
the intended interpretation is as t0310._dt3, so this is what I use.
Unfortunately, several other tools, including SoraVoice and ED6Unpacker, expose
these raw names, and so the filenames need to be converted to the proper format
for use with LB-ARK.
To help with compatibility with such tools, LB-ARK accepts the
$LB_ARK_SPACED_FILENAMES environment variable. If this is nonempty, LB-ARK
will load 8.3 filenames as well. However, this is only intended for local
development; please do not release any mods requiring this to be set.
To substitute a file inside an archive, place the substitute in
data\ED6_DTnn\filename, for example data\ED6_DT21\u7000._sn.
To add custom files, or to keep all your files together, create a data\*.dir
file listing the files to insert or override, in json format.
{
"t0311._sn": "my-mod/t0311._sn",
"0x00010098": "my-mod/file.bin",
"0x00010099": { "name": "myfile.bin", "path": "my-mod/file.bin" }
}The optional "name" key is used for filename lookups; if absent, the name of
the file itself is used.
For technical reasons, the maximum allowed file ID is 0x003FFFFF4.
Additionally, LB-ARK also supports loading plugins from data\plugins\*.dll.
If a function #[no_mangle] extern "C" fn lb_init(); exists, it will be called.
This is unrelated to archive redirection, but it's useful enough to be included.
LB-ARK supports the latest Steam release (as of 2023-03-27) of all three Sky games, both DX8 and DX9 versions. It should be reasonably stable on past and future versions too, but this is untested.
LB-ARK is compatible with SoraVoice, with one caveat: SoraVoice's file redirection
happens before LB-ARK's, meaning if you have files both in voice/scena and
data/ED6_DT21, SoraVoice's are the ones that will be loaded. A script
(move_sora_voice.ps1)
is provided to move a SoraVoice installation into LB-ARK's format.
Footnotes
-
LB-ARK's own lookups for file overrides do no look in specific archives; they look through each archive in numeric order. ↩
-
Including numerous strings found inside the exe and data files, and the file structures of other Trails games, including Sky Evolution. ↩
-
Internal strings give no clear answer on whether to use upper or lowercase names, but all other Trails games use lowercase, so I recommend that convention. That said, NTFS is case insensitive, so it makes no real difference, unlike the spaces. ↩
-
The games as written only support up to 2047 (FC) or 4096 (SC and 3rd) files, but lifting this restriction was easier, and more useful, than coding in this different restriction for each game. ↩