cecilarmitais 702c4c85fe Decomp DeleteWindow and seven window state helpers
Decompile from asm:

  sub_02027A08  0x02027A08      sub_0202811C  0x0202811C
  sub_02028080  0x02028080      sub_0202812C  0x0202812C
  sub_020280C0  0x020280C0      DeleteWindow  0x02028194
  sub_0202810C  0x0202810C      sub_0202822C  0x0202822C

DeleteWindow explains _022A7A74, which the previous commit landed two accessors
for without knowing what it held. On deleting a window it walks the other
nineteen, and for every active one on the same background takes
base_tile + width * height, keeping the largest and a floor of 1, then stores
that at _022A7A74[bg_id]. So the pair is a next-free-tile watermark per
background, which also explains NewWindowScreenCheck setting the entry to 1 when
a background has no windows left: that resets the allocator.

Four of the eight return their callee's result rather than void, and only one of
them shows it. sub_020280C0 never touches r0 after calling sub_02027E30, which
is only consistent with r0 staying live to the return; typed void it scored 90,
typed s32 it scores 5, and the 5 is the literal-pool naming described below.
sub_0202810C and sub_0202811C are tail calls that score 0 either way, so their
own bytes settle nothing; they are typed s32 to match, and a reviewer should
read those two as following the family rather than as read off the target.

DeleteWindow needed two things past the obvious form. The background comparison
is bg == p->template.bg_id, not the reverse, which is worth 5 on its own. And
its four locals have to be declared i, top, p, bg: every one of the 24 orders
was tried, they range from 0 to 140, and only that one reaches 0. The
instructions were already identical at 35 -- the entire remaining difference was
which register held bg and which held i.

sub_0202812C and sub_02027A08 land at 10, and sub_020280C0 at 5, all of it the
literal-pool symbol naming: the target writes _022A8990, _022A8992 and _022A88E4
where C indexing WINDOW_LIST emits WINDOW_LIST+0xb4, +0xb6 and +0x8. Same
address, identical bytes once linked, at a flat 5 per word. The check for this
is in MATCHING_TIPS; the build is what settles it.

struct unk_020AFD4C is introduced for the 12-byte object at that address, sized
by the gap to _020AFD58. Only its word at 0x8 is touched here, a bitmask that
five of these functions set a bit in, indexed by bg_id.

DeleteWindow had a provisional declaration in include/main_0202AAA8.h from the
menu commits, with three decompiled callers. That is replaced by an include of
the new header and all three objects rebuild.

sub_0202836C now has a fifth declaration in the tree, and the existing four do
not agree: overlay_15 says int, overlay_24_end says s32, and overlay_24_init and
overlay_25_init say s8. It is declared s32 here, in the caller's own header
rather than in window.h, so that no overlay including window.h sees a conflicting
one. They should collapse into a single header when the callee lands.

No comments are added to any pmd-sky file.

Authored by Claude (Opus 5) under human direction. Confirmed by a matching
build with the three DeleteWindow callers rebuilt:
build/pmdsky.us/pmdsky.us.nds: OK.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-17 04:42:41 -07:00
…
2026-08-01 12:46:55 -04:00
2026-07-16 07:36:58 -07:00
…
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Pokémon Mystery Dungeon: Explorers of Sky

This is a WIP disassembly of Pokémon Mystery Dungeon: Explorers of Sky. For instructions on how to set up the repository, please read INSTALL.md. For information on how to contribute changes, see CONTRIBUTING.md.

This repository builds the following ROMs:

For contacts and other pret projects, see pret.github.io.

Description
Decompilation of Pokémon Mystery Dungeon: Explorers of Sky
Readme 335 MiB
Languages
Assembly 66.3%
C 18%
C++ 7.1%
Boogie 4.3%
sed 1.5%
Other 2.8%