Song replacement patches

What could be done and really in a easy way is make a console song replacement app. What would be needed? A music ROM map with song data pointers start (1 offset), instruments data start (1 offset) and song ID, name and length of the 255 songs currently in the ROM (255 FF6 song IDs + 255 song names + 255 song data sizes). The second thing needed is all replacement song data and instrument data. If you have 30 replacement song this is 30 .song files and 30 .inst files. If a song name is "Final Countdown", you'd need final_countdown.song and final_countdown.inst. That's pretty much it on Gi Nattak's side.

For the app (let's call it "rotdsmusic"), since the song name would be in a .txt file you read or simply by looking in the app folder, you could just type "rotdsmusic final_countdown" and a list of up to 255 song name choices would pop up in the console. For a song to qualify, final_countdown must have a song data size equal or smaller that a song of the choice list. To keep this simple, if your replacement song data is bigger than all songs in the ROM, you can't replace it. It could be done with extra free space info but let's not get to this yet.

The list choice would be labeled as an example "32 Frog's theme". 32 is a generic ID not related to FF6 song ID (in this case there would be at least choice 01 to 31 prior to this). Many way can used from here but simplest would be you type "32" and Frog's Theme is replaced by Final Countdown. At this point we could even export Frog's Theme data and put the .inst file and .song file with the replacement songs. If you re-run the app, Final Countown would now appear in your ROM choices if you retype "rotdsmusic final_countdown" (song data sizes of 2 copies of the same file are equal). If you want to be really dumb you could even replace all songs smaller or equal to final countdown by final countdown. You'd then have an 80's hack.

This is a few hours of work for me (but not a lot) but if Gi Nattak plan to have more than 10 replacement songs or so, it's something that worth to be done IMO and something that is more flexible than 10 patches. I would not do a GUI app because it would expand my work of twice or three times the time taken to code it.