Patch: allowing use of "reserved" palette colors for player characters

I'm still making the mtek armor sprite in battle work with a custom and/or expanded palette. This has ended up being unreasonably hard for something that wasn't really essential to do. But I'm too invested in it to give up now. I think it's almost done, but I'm still debugging it.

By the way, did anyone notice that you never in the game have mtek armor while you have a full party of four? It's because it steals a palette slot from a PC (along with some video ram). So it can't be displayed correctly unless you have an empty space. Piece of trivia for you -- I never noticed before.

I'm having some trouble thinking about palettes, and the weird multiple ways the game handles them, and how to alter that.

The problem is if I'm going to add over-world palettes 6 and 7 as possible PC palettes, I need there to be at least nine options for battle palettes. That is: the eight overworld palettes (numbered 0-7), plus esper Terra, who on the overworld uses palette 8, and in battle uses battle palette 6, which is a different selection of colors than palettes 6 or 7 for the overworld. Those who have tried to do stuff with palettes know what I'm talking about.

It's not hard to allow selection of palettes beyond the 0-7 range. In the rom, they're stored in a byte, which means they can go up to 256. And, it's not hard to load battle palettes from a larger selection either, since in battle every character gets his own unique copy of his palette anyway, and there's room for four. As long as esper terra is never shown on shops or anything, it's fine.

The biggest concern is ease of editing. I'd rather maintain compatibility with usme and other editors, which only allow you to select battle palette 0-7. I could ask people to hex edit it, or I could write my own custom utility or patching system, but that would be cumbersome, and I'd rather avoid it if I can.

Another possibility is I could always have characters load their overworld palette. It would look it up and retrieve it in battle, shops, and so on, ignoring the existing table(s) in the rom. This means it would have to be set through events, which is a step backwards in terms of ease of editing.

Plus: I can't seem to find the permanent overworld palette in SRAM. Does anyone know where it is?

There are also other solutions where for instance I might only make the map palettes override the battle ones for characters who use o/w palettes 6 or 7. Or Esper Terra might be hard-coded to use her correct palette, and it would not be easily editable. Or I could let you set the battle palette to a dummy value (7 would work), and if it's set to that value, the code would automatically find the overworld palette and load that instead.

And then there's the issue that I'm not even sure all character sprites who appear in battle necessarily have an overworld palette, or whether it's just ones that are associated with a permanent character slot (is that sometimes not true?).

Poco has knowledge about palettes -- I think I learned a lot of what I know from his documents. His thread was recently bumped, but I can't find some of the information I want in it (namely the SRAM locations).

The ideal solution would allow me to simplify palettes, or at least not make them more complicated. It would be nice if every screen could load the same palette automatically, and if this could be set in the ROM, rather than through events. Maybe I could maintain the ability to override the palette through events, in case someone wants to change a PC palette through events (without changing the sprite).

But I can't figure out how to do this without compromising other things, like ease of editing with existing editors.

Any help with these issues, or feedback on what solution would be preferable, would be appreciated.