Persistent cell-state fields: first native check

BB90 serializes two state bits per eligible map cell. BBC6 restores them before regenerating low variant bits at BBFC. Four controlled original-code pack/restore cases establish that ordinary cells preserve 20h and 40h: low variant bits and high bit 80h are not copied by this ordinary packed representation.

Eligibility is determined by the runtime type descriptor at A004 + type*8: descriptor byte FF excludes a cell from this stream. The fixture uses included type 2 and excluded empty type 0. It does not assume every building or beacon is eligible.

The writer is invoked through BC2D from the successful progression path near 3F0A. BC2D selects a state area at saved-record +22h for mode 0, or +3DBh for mode 1, and declines this serialization for modes above 1. Therefore this path supports separate main-city/Halon state streams; it does not establish tunnel persistence through the same mechanism.

This is evidence that selected building-state bits can survive progression, not yet a complete repair policy. BBC6 also has a separate treatment for templates with state bit 80h; that branch and the later variant-index rebuilding are outside this check. Determining which real bank definitions are included, when the saved stream is reset, and whether particular mission damage is repaired remains necessary.

Run PYTHONPATH=/tmp/darker-python python3 tools/verify_persistent_cell_state.py. Results record source bytes, packed byte and restored fields. Source patterns include high and low bits to show which bits survive. The fixture does not exercise disk save I/O or the complete mission transition.

Real bank/map verification

The eligibility viewer now shows included/excluded cells and allows type selection. persistent-map-state.json exports all type IDs, per-map counts and native verification results.

The Halon start is exactly 0022h + 03B9h, independently matching Delphi's measured packed stream length. Ordinary saved damage bits are restored for both cities; this is not a distinction where only Halon has a persistence stream.

Bank 30 excludes types 18,20,22,24; 39–43; and 106–119. Bank 31 excludes 8–23. Every other declared type in those banks is eligible, including Delphi streetlights (11), warehouse roof/interior types (75–77), offices (86–89), energy towers (1), and Halon supply pads (3). Inclusion means a cell participates in serialization, not necessarily that all damage stages have meaningful models for that type.

All 174 bank-32 descriptors are eligible at the codec level, but the normal selector bypasses mode 2. The eight tunnel maps were therefore tested as codec inputs only; this must not be described as proof they are saved during ordinary progression.

The native test serializes synthetic state patterns on all ten real maps using their real bank descriptors, restores them, then executes the low-variant rebuilding at BBFC. Every cell is checked. Per-type variant counters restart from zero and cycle according to descriptor byte +6, so low state bits are regenerated rather than preserved from the source state.

Energy towers and high-bit templates

A restored cell whose fresh template already has bit 80h takes BC27 instead of the ordinary path. The saved two-bit code restores as 00h if zero, FFh otherwise. Main-city map initialization makes its 225 lattice type-1 cells FF, so they take this special path.

As a result, save/restore preserves tower state as binary off/full rather than a fractional fade strength. The codec stores (state >> 5) & 3, not a dedicated state != 0 boolean, so arbitrary intermediate source values can quantize unexpectedly; the normal exit path's queued-outage commit and completed fades help explain why stable endpoints matter. The tests verify the original operation rather than smoothing or normalizing it.

This high-bit handling describes the fresh restore template. It must not be confused with the source state's 80h alternate-model bit, which is not stored independently.

Mission-exit connection

Native exit checks now execute the queued-outage commit and the branch that writes the city state stream. Full next-mission loading, disk save formats and repair/reset paths beyond these routines remain separate.

Run PYTHONPATH=/tmp/darker-python python3 tools/inspect_persistent_map_state.py for the complete real-map checks and viewer.

Failure and reload follow-up

Native real-slot exit/reload chains now confirm that tested failure outcomes retain the earlier committed stream while successful progression saves new damage. Stage byte 1 bypasses restoration. These checks use original city resources and actual slot lookup; outer menu and disk I/O remain separate.