generate-room-elevation

Generate Room Elevation Skill

This skill outlines the process for generating 4-direction unfolded elevations (North → East → South → West) for one or more rooms based on a floor plan in ZWCAD.

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Context

Turns an accepted floor plan into 4-direction unfolded wall elevations (North → East → South → West) in ZWCAD, room by room or for every room at once. Workflow A runs the automated pipeline from derived metadata; Workflow B drives a single room through custom scripting — the split is a role decision, not a preference (see ## Workflow A vs Workflow B).

Execution Steps

1. Preview the plan as SVG from derived metadata (required first step — see ## Step 0).
2. Derive elevation metadata from the reviewed ground truth: finished surface first, then reconcile (## Step 0b).
3. Run Workflow A (selective/all rooms, automated pipeline, recommended) or Workflow B (single room, custom scripting).

Output Format

Four unfolded elevation drawings per room placed on the designated ZWCAD layers, one set per requested room, matching the reviewed rooms.json metadata consumed from cad-svg-preview.

Related Skills

• cad-svg-preview — produces the preview and elevation metadata this skill draws from.
• cad-space-recognition — produces the accepted room ground truth upstream.
• zwcad-ai-drawing — shares the MCP session this skill draws in.

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When to Use This Skill

Use this skill when the user requests to generate elevations for rooms, either:

• Single Room Custom Run: A custom layout or dimensions that require direct coordinates drawing via a script.
• Selective/All Rooms Automated Run: Running the automated pipeline to scan entities (doors/sleeves) from ZWCAD, map them to room bboxes in metadata, and regenerate elevations.

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Workflow A vs Workflow B — Role, Not Just Mechanism

	Workflow A (rematch_openings.py)	Workflow B (draw_room1_elevations.py)
Source of truth	CAD scan + metadata (auto-detected)	Human-verified reference values (ground truth)
Role	Production pipeline — the tool that actually generates elevations day-to-day	Two distinct roles — see below

Because Workflow B's opening offsets are typed in by a human who looked at the drawing (not auto-detected), it doubles as the accuracy baseline for Workflow A: when rematch_openings.py's CAD-scan matching produces a surprising result, draw_room1_elevations.py's hardcoded values — and its per-wall docstring conventions (which corner is "left" on each face) — are what to check it against. Keep this in mind before "simplifying" Workflow B to match Workflow A's automation; its manual, explicit nature is the point.

Workflow B's two roles (see docs/adr/ADR-016-face-elevation-architecture.md Roadmap Addendum for the full rationale):

1. Golden Fixture Generator — its WallDef/Opening data is a human-verified input fixture, independent of how it's drawn.
2. Renderer Oracle — its drawn output is currently treated as "the correct answer" to compare Workflow A's ZWCAD output against. This role is planned to migrate from Workflow B's hand-written draw functions onto a REFERENCE RenderStyle preset once both workflows render through the shared LayoutScene → RendererFactory path (ADR-bb/cc target architecture, not yet implemented) — at that point "the oracle" is a style flag on the shared renderer, not a second hand-maintained implementation.

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Step 0 — Preview as SVG, from derived metadata (required)

Before drawing in ZWCAD:

1. Regenerate the metadata from the user-reviewed ground truth: uv run python scripts/co-architect/cad/pipeline/derive_room_metadata.py "<drawing>". The old hand-built rooms.json/walls.json for the apartment reference plan were wrong (rooms misplaced, C.H 2,800 vs tagged 2,300); these files are now derived and must not be hand-edited.
2. Show the elevations as SVG: render_room_elevation_svg.py --rooms memory/drawings/<drawing>.rooms.json <out_dir> renders every room, including non-rectangular ones, and all-rooms.svg. See skill cad-svg-preview.
3. Draw in ZWCAD only after the user confirms the SVG.

rematch_openings.py takes C.H from rooms.json first, then the existing walls.json, then architectural-standards.json. The hard-coded 2,800 default is gone. Non-rectangular rooms are skipped by this 4-face pipeline with an [INFO] line.

Step 0b — Elevations are drawn from the plan: finished surface, then reconcile

Elevation sheets are drawn from the plan sheet (reading rules R27, R28). Example: the public-hall drawing in tests/, where sheet 1 is the plan and sheets 2–3 are elevations A–F.

1. Which walls: the key plan's marker pair (A/A′ …) and its coloured section line name the plan space and walls of each elevation. Record them in the ground truth under elevations (space, marker_y) and sheets (plan → elevation sheets).
2. Which surface: elevations are dimensioned to the finished wall surface, the structural face minus the finish. Put plan polygons on the drawing's own wall centerlines (for example the A-CEN layer) and set _meta.wall_finish_mm. room_metadata.unfolded_faces(..., finish=) then produces the sheet dimensions (for example, the lobby is 2,350 at the concrete face and 2,310 on the sheet).
3. Reconcile: derive_room_metadata.py runs elevation_scoring.score_drawing when the drawing has elevation sheets and writes {drawing}.elevation-score.json. The targets are unfolded length within 100 mm and every sheet door matched (position within 260 mm, width). Treat every review line as a question. Record a real plan-vs-sheet drafting difference in the ground truth instead of forcing a match.

Workflow A — Selective/All Rooms Automated Pipeline (Recommended)

Use this workflow to automatically extract openings (doors/windows/sleeves) from the active ZWCAD drawing, reconcile them with floor plan metadata, and regenerate elevations.

[!NOTE] --render-mode simple is a schematic mode by design, not an incomplete detailed. It intentionally omits brick/concrete hatch and door/window detail (plain rectangle + WxH label only) — see docs/adr/ADR-016-face-elevation-architecture.md ADR-aa. Don't "complete" it by copying detailed geometry into it; if a use case needs that, use detailed instead.

Workflow B does not support --render-mode at all — it always draws one fixed, hand-authored style. See ADR-aa's "Known parity gap" note and the "Roadmap Addendum: Simple/Detailed Rendering Parity & Workflow A/B Convergence" section in the same doc for the planned convergence (Workflow B onto the shared ZWCADRendererFactory) and the current door-symbol mismatch between Workflow B's true arc and detailed/door.py's straight-line approximation.

Step A1: Verify Metadata Availability

Before running, ensure the drawing metadata is extracted and available under memory/drawings/ (usually extracted from memory/drawings.zip if compressed):

• {drawing_name}.rooms.json: Contains the user-verified room bboxes and nominal openings.
• {drawing_name}.walls.json: Contains wall dimensions and opening metadata.
• {drawing_name}.layers.json: Contains layer classifications (e.g. wall layers, door layers).

[!IMPORTANT] Strict Metadata Isolation: The elevation pipeline enforces Fail-Fast validation. Metadata is treated as belonging to exactly one drawing. Reusing metadata generated for another DWG is unsupported and results in immediate validation failure.

Step A2: Execute Pipeline

Option 1: Generate for ALL Rooms

Run the following command to process and generate elevations for all rooms:

.venv\Scripts\python.exe scripts/co-architect/cad/pipeline/rematch_openings.py

Option 2: Generate for SELECTIVE Rooms

To generate elevations only for specific rooms, pass their comma-separated names using the --rooms flag:

.venv\Scripts\python.exe scripts/co-architect/cad/pipeline/rematch_openings.py --rooms "ROOM #1,ROOM #2"

Step A3: Verification

1. Run the verify_drawings.py verification script (standalone scratch checker) to check the generated entities.
2. In ZWCAD, confirm that:
   • Old elevations on elevation layers are deleted and replaced.
   • The generated elevations are rendered to the right of the floor plan (standard starting position X = 50000 with 5000mm spacing).

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Workflow B — Single Room Custom Scripting

Use this workflow when a room requires ad-hoc layout changes or does not match the automated database.

Step B1: Extract Room Dimensions

1. Locate the room text label inside the active drawing to determine its center coordinates.
2. Verify the East-West (EW) and North-South (NS) span sizes from the dimension lines or polyline vertices.
3. Identify opening types (door, window) and their exact offset and width from the wall corner.

Step B2: Configure the Scaffold Script

Create or copy a script (e.g., draw_room1_elevations.py) and specify:

• Room width (room_ew), height (room_ns), and ceiling height (ceiling).
• Wall openings formatted as (type, offset, width, sill, height).

Step B3: Execute and Save

1. Execute the custom script:

   .venv\Scripts\python.exe scripts/draw_<room>_elevations.py
   

2. Save the active document in ZWCAD:

   .venv\Scripts\python.exe -c "import win32com.client; win32com.client.GetActiveObject('ZWCAD.Application').ActiveDocument.Save()"
   

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