SectorForge

SectorForge is an AI-powered dungeon and map generation engine designed for science-fiction tabletop campaigns. It ships as a Claude Code plugin: you describe a location, Claude designs the deck layout, and a deterministic engine renders a top-down battlemap while auto-deriving walls, doors, and dynamic lighting — exporting files that drop straight into Foundry VTT (v13/v14) and any Universal VTT-compatible tabletop (Roll20, Fantasy Grounds, Arkenforge…).

Maze/warren layouts and organic texturing (eldritch_void theme) — winding corridors, branches, and dead ends, with mottled stone, cracks, wall growth, and spores:

The procedural renderer is deterministic vector art — much richer than flat tiles, but not hand-painted. For a fully painted, illustrated look, use the hybrid path: the engine carries the layout + walls/lights, an image generator paints the background from the emitted prompt, and repack_image.py recombines them so Foundry walls still work.

LLM for creativity, code for VTT-data correctness: Claude never hand-places walls — they're derived from the floor boundary, so line-of-sight and lighting just work on import.

What you get per map

File	What it is
<name>.png	Top-down procedural sci-fi battlemap (evenly lit, grid-aligned).
<name>.dd2vtt	Universal VTT — image + walls + doors + lights. The portable, cross-VTT format.
<name>.fvtt.json	Native Foundry scene (v13/v14 data model).
<name>.prompt.txt	z-image/ComfyUI art prompt for the optional hybrid path.

Install

SectorForge is a Claude Code plugin. It does not need a server — this git repo is all the "hosting" required. The repo is both a plugin (at the root) and a one-plugin marketplace (.claude-plugin/marketplace.json).

Requirements: Python 3.9+ and Pillow (pip install Pillow).

Install from GitHub (in Claude Code):

/plugin marketplace add dakesec/SectorForge
/plugin install sector-forge@sectorforge

Install from a local clone (no GitHub needed) — point the marketplace at the folder instead:

/plugin marketplace add /absolute/path/to/SectorForge
/plugin install sector-forge@sectorforge

After installing, restart Claude Code if prompted. Then use /dungeon … or just ask for a sci-fi battlemap.

Using it in regular Claude Desktop / Claude.ai chat threads (not Claude Code): those threads can't load Claude Code plugins, but they can load an uploaded Agent Skill. Grab dist/sector-forge.skill and upload it via Settings → Capabilities → Skills. See dist/README.md.

Verify the engine (optional, standalone):

python scripts/build_map.py examples/derelict-station.json --out out

You should get a PNG, a .dd2vtt, a .fvtt.json, and a prompt in out/.

Use

In Claude Code:

/dungeon derelict mining station — reactor core, 3 crew quarters, med-bay, bridge; emergency lighting, derelict_industrial theme

Or just ask in natural language ("make me a Foundry battlemap of a research station overrun by something…") — the sector-forge skill activates automatically.

Claude writes a map-spec JSON, runs the engine, shows you the map, and hands you the VTT files. Iterate by asking for changes — the engine is deterministic, so the same spec always yields the same map.

How it works

narrative direction
      │  (Claude designs)
      ▼
 map-spec JSON  ──►  geometry.py  ──►  walls + doors + line-of-sight
      │                                (auto-derived from floor boundary)
      │  build_map.py
      ▼
  render.py  ──►  PNG          exporters ──►  .dd2vtt  +  .fvtt.json (v13/v14)

The hybrid path swaps the procedural PNG for AI art:

<name>.prompt.txt ─► ComfyUI z-image ─► art.png ─► repack_image.py
                                                   └► .dd2vtt + .fvtt.json (art bg, same walls)

With a local ComfyUI, run the whole hybrid in one command:

python scripts/comfyui_submit.py spec.json --workflow workflow_api.json --out out

Setup (install ComfyUI + Z-Image Turbo, export an API workflow, title the SECTORFORGE_PROMPT / SECTORFORGE_INIT nodes) is in skills/sector-forge/references/comfyui-hybrid.md.

Foundry v13/v14 notes

The Foundry exporter targets the v13/v14 Scene data model:

• Walls carry the v12+ threshold object; sense/movement use the stable 0/20 enums; doors use door/ds.
• Lights emit the fuller v13/v14 AmbientLight config (negative, priority, coloration, attenuation, animation, darkness range…).
• The removed top-level globalLight / darkness / fogExploration fields are replaced by the environment and fog objects. The map-spec darkness (0–1) drives environment.darknessLevel.

Foundry cleans unknown fields and fills defaults on import, so minor version drift is tolerated. The .dd2vtt path is the most version-stable if you hit a schema mismatch.

Layout

SectorForge/
├── .claude-plugin/plugin.json
├── commands/dungeon.md                 # /dungeon slash command
├── skills/sector-forge/
│   ├── SKILL.md                        # how Claude turns direction → spec → files
│   └── references/
│       ├── map-spec-schema.md          # full spec field reference
│       ├── themes.md                   # themes, floors, props, lighting
│       └── vtt-formats.md              # export formats + import steps
├── scripts/
│   ├── build_map.py                    # spec → PNG + UVTT + Foundry + prompt
│   ├── geometry.py                     # occupancy + wall/door derivation
│   ├── render.py                       # procedural tile rendering (Pillow)
│   └── repack_image.py                 # hybrid: swap in AI art, keep VTT data
└── examples/
    └── derelict-station.json           # worked example

Notes & limitations

• Rooms can be rect, circle/ellipse, diamond, octagon, or polygon — overlap shapes to compose complex spaces. Round rooms are grid-aligned (stair-stepped), matching how VTT walls and line-of-sight work.
• Doors use the connection form {from, to} and snap to the actual opening between rooms, so they always line up with the passage. autoDoors seals every room↔corridor opening at once.
• Props are decorative (non-collidable). Model sight-blockers as tiny rooms.
• Foundry's scene schema shifts across major versions; the .dd2vtt path is the most version-stable. The Foundry JSON targets v13/v14.
• Single deck per spec. For multi-level stations, make one spec per deck and note the stair/lift connections.

License

GPL-3.0.