Entry 302

DUNGEON::ShowMap's two edges: DeleteRoom frees the one built room, and room 15 is never under the player

2026-09-28renderworld

Filescrates/piney-world/src/map/dungeon.rs

301 left two places where the port's show_map_step looked different from DUNGEON::ShowMap (INF GCMN.PRG:0x005cf260). Neither is a difference the port can or should copy, so no code changed.

DeleteRoom frees the built room, whatever room it is given

301 read DeleteRoom(level, here) as freeing only the slot room[level][here]. The code says otherwise (INF GCMN.PRG:0x005c1980):

• Only one thing is indexed by the arguments: the ccAnm at this + 0x2f230 + level * 60 + room * 4 (15 rooms a floor), which SetRoom (0x005c1ca0) allocates at 0x005c1d74.
• Everything else it frees is the single built room, whichever it is: ccClutRoll +0x404, the ccAnm +0xd38bc, the room's ccClump +0xd3880, the light group +0x370, the ccAnms +0x364 (3), the LEAFs (20), SNOWs (60), FIREFLYs (5), the clumps and anms of the ten objects, the ROOMLIGHTs (32) and the ccAnms +0x3f4 (4).

The port's delete_room drops the built room whole, which is the same. The only gap is the GotoNextRoom window (301), where the room built is not here. There the game frees the built room anyway and leaks its ccAnm object. DUNGEON::Draw draws only room[level][here], so nothing of it is shown.

Room 15 under the player

The cell lookup (0x005cf300-0x005cf404) is the port's here: cell ((30000 + x) / 750, (30000 - y) / 750), byte +0x432. Its "no room" value is 15 (piney_data::dungeon::NO_ROOM), not 0xff as 301 had it. With 15 the game would run:

• DeleteRoom(level, 15): the ccAnm slot 15 of a 15-slot row is the next floor's slot 0, which is empty while only this floor's room is built;
• SetRoom(level, 15): its own tables are read past each floor's 15 rows, with a different stride in each, so it builds no real room.

A player only stands on a room's cells. Door cells belong to their room. Every other cell is outside the walls the collision keeps him in. So the game never takes this path in play. The port skips the rebuild there, because copying out-of-bounds reads with no source for their values would be guesswork.