Scripts

SoE uses scripts with custom instructions (byte code) for things like opening chests, dialog, etc.

Active scripts are stored in $7e28fc onward with 0x4f bytes per script "slot".

• Bytes +0..+2 are script's current instruction address (as 24bit bus address).
• Byte +3 defines the script's status (e.g. filled/active).

Scripts are being added to the list through code at $8ccf18 (JSL there).

• Address (+0..+2) is set from $26..$28 + #$920000 excluding lower half banks by shifting #$8000 bit[^1].
• Status (+3) is set to 2.
• Script arguments (and caller?) are copied from $7e0e80..93 to +0x0f..0x22.

Added scripts have to be "activated" by writing their 16bit address (in X after executing $8ccf18) to the list in $7e2f28.
The offset to the next free slot in that list is stored in $86, which has to be incremented afterwards.
See patches/multiworld.txt for an example

[^1]: basically 000bbbbb baaaaaaa aaaaaaaa becomes #$920000 + 00bbbbbb 1aaaaaaa aaaaaaaa
This is due to how continuous rom addressing in hirom works.
For example $000000 becomes $928000, $008000 becomes $938000.

Reused scripts

• Mammoth graveyard viper 1-4 death scripts are identical. We change 1-3 to use 4, freeing up
  • 17d3: currently unused
  • 17d6: currently unused
  • 17d9: currently unused
  • 17dc: viper 1-4