# GC-style song selection

Running the stage player without a stage path opens the graphical song
selector backed by `data/boot/stage_param.dat`:

```sh
./tools/run_stage_player.sh
```

Passing a stage remains the direct reverse/debug path:

```sh
./tools/run_stage_player.sh GC/data/stage/ac_oshama_hard.dat
```

The selector renders the original English `selectmusic2` and `selectmode2`
RVB/MTX scenes. Exact task flow, coordinates, animation bindings, and the
container reverse are recorded in `docs/re_gc_menu_exe.md` from
`game471.exe` itself.

What is already wired:

- the original portrait 720x1280 `SELECT MUSIC` and `SELECT MODE` scenes;
- original MovieClip frame labels, display-list depth updates, transforms,
  alpha fades, and RGB color transforms;
- the original `common_eng` controller HUD and animated Yume navigator scenes;
- the executable's purple-to-pink background strip, rotating wire sphere,
  translucent menu geometry, and `balloon.dds` lower backing layer;
- the eight original sort tabs, with genre headings and catalog-backed title,
  difficulty, newest and random ordering;
- the twelve dynamically linked `mc_music_link`/`mc_index_link` carousel
  slots with their executable positions and opacity table, including original
  `s_j_eng.dds` genre headings as real scrolling entries;
- title rows, jacket, source and artist cut directly from each original
  `data/stage/2d/<imageKey>_menu.dds` atlas;
- SIMPLE/NORMAL/HARD/EXTRA availability and selected-state MovieClips from the
  same catalog;
- separate select-music and difficulty states, matching the task transition
  proven in the executable;
- launch through the selected difficulty's exact `ac_*` stage ID.

Entries are included only when both their menu atlas and at least one local
stage `.dat` exist. This dump currently yields 887 playable songs from the 924
master catalog records. Only the visible carousel window is uploaded to the
GPU, rather than all jackets at once.

Controls:

```text
Up / Down, W / S       previous / next song
PageUp / PageDown      jump by eight songs
Q / E or Tab           song order
Enter or Space         enter difficulty screen
Escape                 close selector

Difficulty state:

```text
Arrows, W / S, A / D   difficulty
Enter or Space         play
Escape                 back to music selection
```