OBD talk:Oni2AS

Using this page to write up instructions for a straightforward patch allowing one to specify alternative/additional layouts in Settings/rb.gamedata

The file table entries for Settings/rb.gamedata and fonts/rbstrings.xls look like this:

Offset	Type	Raw Hex	Value	Description
File table, 8881st entry
0x23300	offset	26 BC 04 00	0x4BC26	offset to file name, from start of file name block, in bytes in this case it points to 0x800+0x41800+0x4BC26=0x8DC26 the string at that address is fonts/rbstrings.xls (null-terminated)
0x23304	offset	00 88 7C 02	0x27C8800	absolute offset to file data, from start of DAT file, in bytes
0x23308	int32	00 52 00 00	20992	uncompressed file size, in bytes
0x2330C	int32	12 15 00 00	5394	compressed file size, in bytes
File table, 16456th entry
0x40C70	offset	98 10 0A 00	0xA1098	offset to file name, from start of file name block, in bytes in this case it points to 0x800+0x41800+0xA1098=0xE3098 the string at that address is Settings/rb.gamedata (null-terminated)
0x40C74	offset	00 50 0E 00	0xE5000	absolute offset to file data, from start of DAT file, in bytes
0x40C78	int32	C7 02 00 00	711	uncompressed file size, in bytes
0x40C7C	int32	29 01 00 00	297	compressed file size, in bytes

RB.DAT patch

Adding all layouts to Settings/rb.gamedata could be as simple as making the following value changes to RB.DAT (after making a backup)

Address	Old value	New value
0x23304	00 88 7C 02	22 D3 1D 02
0x23308	00 52 00 00	00 00 00 00
0x2330C	12 15 00 00	00 00 00 00
0x40C74	00 50 0E 00	00 88 7C 02
0x40C78	C7 02 00 00	70 12 00 00
0x40C7C	29 01 00 00	70 12 00 00

and replacing 4720 bytes of RB.DAT starting at 0x27C8800 with the byte-for-byte contents of THIS file.

ISO patch

To avoid the trouble of making a PS2-compatible ISO, one can instead make the following changes directly to oni2dev_ps2.iso or whatever it's called (after making a backup)

Address	Old value	New value
0x37A304	00 88 7C 02	22 D3 1D 02
0x37A308	00 52 00 00	00 00 00 00
0x37A30C	12 15 00 00	00 00 00 00
0x397C74	00 50 0E 00	00 88 7C 02
0x397C78	C7 02 00 00	70 12 00 00
0x397C7C	29 01 00 00	70 12 00 00

and replace 4720 bytes of the same oni2dev_ps2.iso starting at 0x2B1F800 with the byte-for-byte contents of THIS file.

Indeed, the RB.DAT file is stored as-is in the ISO, with a 0x357000 offset.

UNFORTUNATELY...

The game can only load 63 layouts at once without complaining. So one needs to provide a smaller Settings/rb.gamedata file, or at least one that announces fewer layouts in the first line. Like THIS ONE (first 63 layouts) or THIS OTHER ONE (last 32).

Alternative idea if you don't want to overwrite the Excel file

As it happens, Settings/rb.gamedata is the file whose data, at 0xE5000, is the one that comes first, and between it and the preceding string data there are 1866 bytes of unneeded space. Together with the 297 bytes of the file itself, that allows for 2153 bytes of plain text, which is enough to list a lot of the layouts, if not all of them.