[byRandom]

The first two items of 0.6: mineshafts are now checked the same way the game checks them, so nothing on the map or in the finder is marked as "possible" any more. This also does proposal #3 of the architecture review: the unknown state is removed from every layer.

Mineshafts

• A mineshaft's generation point depends on its pieces. The game grows a room, corridors, crossings and stairs from the chunk, then moves the whole mineshaft:

  • normal mineshafts go below sea level;
  • badlands mineshafts move so that the box's center lands between sea level and the surface.

  The biome is checked at the height that results from that move.

• New structure::mineshaft ports MineshaftPieces far enough for that: every piece's bounding box, in the game's order, drawing the same random numbers. That includes the corridor's rail and spider-web rolls, which only decorate.

• New kind StructureKind::Mineshaft(MineshaftType), exported by the oracle.

No more "possible"

• Removed Outcome::Unknown, StructureKind::NotImplemented, Found.exact and Marker.exact, plus the app's "possible" labels, inspector status and help text.
• try_structure now returns Option<pos> instead of a nested Option.
• A Hit always has a structure that generates.
• Only the spawn block is still shown as an estimate.
• The oracle now throws on a structure type it does not know, instead of exporting it as not implemented.
• The structures example now lists mineshafts and buried treasure too.

Verification

• New game fixtures, appended after the existing generators. The existing fixtures did not change.
  • mineshaft_pieces.txt: 800 whole piece lists (101,148 pieces), each with the random number that comes after it.
  • mineshaft_points.txt: 2,160 generation points of both types, on clusters centred on their biomes. 840 of them are badlands mineshafts that generate.
• The 117 mineshaft attempts already in structures.txt now match the game as well.
• Mutation testing: 12 of 13 mutations fail a test. Among them are the distance and depth limits, the random draws, the two-floor threshold, collisions, the badlands centre and the sea-level offset. The remaining one is equivalent and is recorded in docs/PARITY.md.

No version bump: 0.6 still needs saved settings.

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Generated by Claude Code