New maps and map selectormain

1 files changed, 29 insertions, 7 deletions

diff --git a/CLAUDE.md b/CLAUDE.md
index 4234a9b..a859f8d 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -37,7 +37,10 @@ refuses a plain re-setup), `make shell` (interactive container), `make clean`,
   layers don't rebuild) unless it must come earlier.
 
 **Verify without a display:** you can't run the GUI in the container, so validate
-by (a) compiling clean and (b) parsing the Lua data. `make check` does both.
+by (a) compiling clean, (b) parsing the Lua data and (c) settling every map in
+the headless soak test (`tools/sim_check.cpp` — the solver needs no display, so
+it catches "the fort collapses on load"). `make check` does all three;
+`make sim-check SOAK=20` for a longer settle.
 Note mods must be validated **layered** (base file first) because they
 `table.insert` into globals the base defines — `make check-lua` already does
 this; running a mod file standalone always fails.
@@ -114,14 +117,30 @@ the ImGui Dev panel** — use it; the constants were tuned by eye, not proven.
 
 Game content is **Lua data**, loaded at startup. This is the seam mods hook into.
 
-Base files in `data/`: `materials.lua`, `weapons.lua`, `devices.lua`,
-`structures.lua`, `map.lua`. Each defines a global table (`Materials`, `Weapons`,
-`DeviceDefs`, `Structures`, `Deposits`/`MapDevices`) plus `Find*`/`IndexOf*` helpers.
+Base files in `data/`: `materials.lua`, `weapons.lua`, `devices.lua`, `maps.lua`.
+Each defines a global table (`Materials`, `Weapons`, `DeviceDefs`, `Maps`) plus
+`Find*`/`IndexOf*` helpers.
+
+**Maps** (`data/maps.lua`) are the selectable scenarios: each entry bundles
+`ground_level`, `deposits`, `devices`, the player's starting `weapons`, and the
+prebuilt `structures` (lists of `{x1,y1,x2,y2,material}` beams). `Maps[1]` is the
+default; the Dev panel's **Map** section switches between them at runtime, which
+tears the graph down and rebuilds it via `build_map()`. Beams must be within the
+material's `max_length` (they are welded raw, **not** auto-subdivided) and must
+be triangulated, or the fort hinges apart on the 30° angle rule.
+
+> **Gotcha:** clearing `graph.nodes`/`graph.edges` does **not** clear the private
+> `adj_`/`edge_set_` caches. Call `graph.rebuild()` straight after clearing, or
+> the stale edge keys make `add_edge` reject the next map's beams as duplicates
+> and the fort silently loads half-built. `build_map` warns on every rejected
+> beam; `make sim-check` catches the collapse.
 
 **Layered loader** (`data.cpp::run_layered`): base file runs first, then every
 `data/mods/<name>/<file>.lua` runs on top in **(priority, name)** order, mutating
 or extending the global tables — exactly like Forts. A mod's `mod.lua` sets
-`Priority`. Example: `data/mods/enemy-fort/` adds the target fort + enemy reactor.
+`Priority`. Example: `data/mods/enemy-fort/maps.lua` uses `FindMap()` to bolt
+extra armour plating onto the Proving Ground enemy fort — the worked example of
+a mod mutating base data rather than replacing it.
 
 To add content, prefer **editing Lua data** over hard-coding C++. When you must
 add a field, add it to the `*Def` struct, read it in `data.cpp` (`get_or` with a
@@ -168,8 +187,11 @@ See `requirements/milestones.org` for the live checklist. Roughly:
   device framework + placement. Two gaps: fire does **not** damage devices, and
   devices are not mounted on the strut graph, so the "cut its supports and the
   reactor falls" victory path does not exist.
-- **M6 partial:** enemy fort (`data/mods/enemy-fort/`) + deposits both sides;
-  terrain is still a flat half-plane and there is no sky backdrop.
+- **M6 partial:** three selectable scenarios in `data/maps.lua` (Proving Ground,
+  Iron Bastion, The Narrows), each with its own forts, deposits, player starter
+  structure and weapon spawns, switchable from the Dev panel. Terrain is still a
+  flat half-plane — maps can move the ground up and down but not change its
+  shape — and there is no sky backdrop.
 - **Not started / later:** repair & recycle (M7), armour/door/shield materials,
   tech tree + upgrades, commanders, real map/terrain, AI, netcode.