crosstech-impl-ifc-to-threejs
Installation
SKILL.md
crosstech-impl-ifc-to-threejs
Quick Reference
Technology Boundary
| Aspect | Side A: IFC / web-ifc | Side B: Three.js |
|---|---|---|
| Data model | IFC entities with properties, relationships, geometry | Scene graph: Object3D, Mesh, BufferGeometry |
| Coordinate system | Z-up (Z vertical, X/Y ground plane) | Y-up (Y vertical, X/Z ground plane) |
| Geometry format | Parametric (extruded solids, BREP, CSG) | Tessellated triangles (BufferGeometry) |
| Properties | IfcPropertySet, IfcElementQuantity via relationships | NOT stored in scene graph — userData only |
| Materials | IfcSurfaceStyle, IfcMaterialLayerSetUsage | MeshPhongMaterial, MeshStandardMaterial |
| Identifiers | expressID (integer per entity) | Object3D.userData or Fragment index |
| Directionality | IFC → Three.js (one-way rendering) | No write-back to IFC |