--- name: spec-to-3d description: >- Generate 3D building models from architectural specifications, parsed drawings, or building code data. Outputs Three.js geometry, Pascal Editor JSON, or plain JSON for IFC conversion. Use when: converting floor plans to 3D, building spec-driven 3D models, generating architectural visualizations from structured data. license: Apache-2.0 compatibility: "Node.js 18+, Three.js or Pascal Editor" metadata: author: terminal-skills version: "1.0.0" category: design tags: [3d-modeling, architecture, three-js, ifc, building-generation] --- # Spec to 3D -- Building Model Generator ## Overview Convert structured architectural data (from `architectural-drawing-parser` or manual specs) into 3D building models. Supports three output formats: **Three.js** (interactive web viewer), **Pascal Editor JSON** (BIM-style node graph), and **plain JSON** (for IFC/GLB conversion). Works as the final stage in a drawing-to-3D pipeline alongside `architectural-drawing-parser` and `ibc-building-codes`. ## Instructions ### Pipeline ``` Architectural Drawing (image/PDF) | architectural-drawing-parser Structured BuildingData JSON | ibc-building-codes (validation) Validated Building Data | spec-to-3d (THIS SKILL) 3D Model Output: - Three.js Group (web viewer) - Pascal Editor JSON (BIM node graph) - Building3D JSON (for IFC/GLB export) ``` ### Input Requirements The generator expects a `BuildingData` object with: - **stories** -- `{ permitted, actual }` (number of floors) - **units** -- Array of `{ name, area: { sqft, sqm }, occupantLoad }` (unit types per floor) - **height** -- `{ permitted, actual }` in feet and meters - **occupancy** and **constructionType** -- for IBC validation context ### Generation Logic 1. **Floor-to-floor height**: Default 9'-0" (2.74m) per IBC R-2 residential standard (7'-0" minimum habitable) 2. **Unit dimensions**: Derived from area using 1:1.5 aspect ratio (width:depth). Override for corridor-loaded or deep units 3. **Wall thickness**: 300mm exterior, 150mm interior partitions (US wood frame standard) 4. **Layout**: Units placed side-by-side per floor with 150mm party walls, common corridor along one side (5'-0" / 1.52m wide) 5. **Stairs**: Two stairwells at building ends, 4'-0" wide x 10'-0" deep 6. **Room subdivision**: Automatic based on unit area -- studio (<50 sqm), 1-bed (50-70 sqm), 2-bed (>70 sqm) ### Output Formats | Format | Use Case | Description | |---|---|---| | `json` (Building3D) | IFC conversion, custom renderers | Plain data: levels, units, rooms, walls, openings | | `pascal` (Pascal Editor) | BIM workflows | Node graph with site > building > level > wall/room hierarchy | | `threejs` (THREE.Group) | Web-based 3D viewer | Mesh geometry with materials for floors, walls, windows | ### Key Interfaces ```typescript interface Building3D { levels: Level3D[]; totalHeight: number; // meters footprintWidth: number; footprintDepth: number; } interface Level3D { elevation: number; // meters above grade height: number; // floor-to-floor in meters units: Unit3D[]; corridors: Box3D[]; stairs: Stair3D[]; } interface Unit3D { type: string; position: { x: number; y: number; z: number }; width: number; depth: number; height: number; // meters rooms: Room3D[]; walls: Wall3D[]; openings: Opening3D[]; } ``` ## Examples ### Example 1: Converting a Building Spec to a 3D Model A developer has parsed data from an IBC compliance sheet for a 3-story R-2 apartment building and wants to generate a 3D model for visualization. ``` Input BuildingData: occupancy: R-2, constructionType: V-B, sprinklerSystem: NFPA 13 stories: { permitted: 4, actual: 3 } units: - Type A: 834 SF (77.5 sqm), 5 occupants - Type B: 645 SF (59.9 sqm), 4 occupants Generated Building3D (format: "json"): Level 0 (Ground Floor): elevation 0.00m, height 2.74m Type A: 7.19m wide x 10.78m deep (2-bedroom layout: living, kitchen, master bed, bed 2, 2 baths) Type B: 6.32m wide x 9.48m deep (1-bedroom layout: living, kitchen, bedroom, bath) Corridor: full building width x 1.52m deep 2 stairwells at building ends Level 1: elevation 2.74m, height 2.74m (same layout) Level 2: elevation 5.49m, height 2.74m (same layout, no stairs above) Total height: 8.23m Footprint: ~13.66m x 10.78m Wall count: 12 exterior + 8 interior per floor Openings: 1 door + 2 windows per unit ``` ### Example 2: Generating IFC-Compatible Output An architect needs to export the building data for use in an IFC/BIM workflow. They generate Pascal Editor JSON that maps to a site > building > level > element hierarchy. ``` Input: Same 3-story R-2 building as Example 1 Output format: "pascal" Generated Pascal Editor JSON: { "nodes": { "site_1700000000": { "type": "site", "parentId": null }, "building_1700000000": { "type": "building", "parentId": "site_...", "width": 13.66, "depth": 10.78, "height": 8.23 }, "level_0": { "type": "level", "name": "Ground Floor", "elevation": 0.00, "height": 2.74 }, "level_1": { "type": "level", "name": "Level 1", "elevation": 2.74, "height": 2.74 }, "level_2": { "type": "level", "name": "Level 2", "elevation": 5.49, "height": 2.74 }, "wall_0_0": { "type": "wall", "parentId": "level_0", "start": { "x": 0, "y": 0 }, "end": { "x": 7.19, "y": 0 }, "thickness": 0.30, "isExterior": true }, "room_0_0": { "type": "room", "parentId": "level_0", "name": "Living Room", "roomType": "living", "width": 4.31, "depth": 4.31 }, ... (60+ nodes total across 3 levels) }, "rootNodeIds": ["site_1700000000"] } This JSON imports directly into Pascal Editor or can be converted to IFC using ifcopenshell. ``` ## Guidelines - Floor-to-floor height defaults to 9'-0" (2.74m); override if the source drawing specifies otherwise - Unit aspect ratio defaults to 1:1.5; corridor-loaded or deep units may need 1:2 or higher - Window and door positions are generated algorithmically; use `architectural-drawing-parser` room extraction for actual positions from drawings - The Three.js output creates simple box geometry -- suitable for massing models and spatial validation, not photorealistic rendering - For production BIM use, export to Pascal Editor JSON and refine in a BIM tool - Stair geometry is simplified (box representation); detailed stair modeling requires a dedicated BIM tool - All dimensions are in meters internally; input data in feet is converted using 1 ft = 0.3048 m