3 interior walls limitation

From what I understand Zelda 3 is limited to only have 3 types of indoors wall graphics.

1. Houses

2. Cave

3. Dungeon

I would love to be able to expand on this and have more than just 3 different graphics to choose from.

Does anyone here know if this can be expanded and how difficult or easy this is?

Thanks.

Yes there can be expandet but you need knowledge about the graphics scheme function and you need for each new wall blockset 2 tilesets and this are limited. :-)

Ps: You have 1 for houses, 1 for caves and 4 for dungeons (lightworld dungeons, dark world dungeons, the ice dungeon and ganon's tower).

Officially the game is capable of loading around 12 different values when entering any indoors, but some of them are repeating, to come to around 8. But the dungeons seem almost identical, because of the lack of gfx space. This basically means having 6 completely different interior wall-blocksets at maximum.

Spane is one of those rare people, who actually managed to change this completely, to brand new wall-blocksets. If keeping the cave and house for obvious reasons, 4 new dungeon wall-blocksets can be defined, and Spane managed to change the palettes also, resulting in some brand-new-looking dungeons. He also changed the door gfx accordingly.

Oh, yeah I totaly forgot about this picture above, when you managed to make 24 wall-blocksets, but I know you were also using overworld tilesets for dungeons (so you must have less overworld tilesets then).