The headless "IfcOpenShell" calculator had all Qto_SpaceBaseQuantities
formulas set to null for IfcSpace in both IFC4QtoBaseQuantities.json and
IFC4X3QtoBaseQuantities.json, so qto.py's `if not formula: continue`
skipped every quantity, no geometry task was queued, and spaces never
appeared in results (elements_quantified: 0). The Blender calculator
already computes these; they were just never ported to the
ifcopenshell.util.shape-backed calculator.
Map the eight computable quantities to existing util.shape functions,
mirroring the Blender calculator semantics (no new shape.py code):
GrossFloorArea=gross_get_footprint_area, NetFloorArea=net_get_footprint_area,
GrossCeilingArea=gross_get_top_area, NetCeilingArea=net_get_top_area,
GrossPerimeter=gross_get_footprint_perimeter, GrossVolume=gross_get_volume,
NetVolume=net_get_volume, Height=net_get_z.
Left null (matching the Blender ruleset, not guessed): GrossWallArea,
NetWallArea, NetPerimeter (Blender stub), and FinishFloor/CeilingHeight
(Blender derives these from sibling IfcCovering decomposition geometry,
which this per-element calculator architecture can't reach).
Verified on IFC4 (4x3 space extruded 2.5m): before -> {} / elements_quantified 0;
after -> GrossFloorArea 12, GrossPerimeter 14, Height 2.5, GrossVolume 30,
etc. - all exact matches to the extrusion. IFC4X3 formulas are identical
and the formula->function resolution is schema-agnostic.
Scope: fixes the IfcSpace case (the issue title). The 12 other all-null
classes noted in the issue (IfcDoor, IfcSite, IfcRailing, ...) are left as
follow-up.
This change was made with the assistance of an AI tool.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
IfcOpenShell
IfcOpenShell is an open source (LGPL) software library for working with Industry Foundation Classes (IFC). Complete parsing support is provided for IFC2x3 TC1, IFC4 Add2 TC1, IFC4x1, IFC4x2, and IFC4x3 Add2. Extensive geometric support is implemented for the IFC releases IFC2x3 TC1 and IFC4 Add2 TC1. Extending with support for arbitrary IFC schemas is possible at compile-time when using C++ and at run-time when using Python.
In addition to a C++ and Python API, IfcOpenShell comes with an ecosystem of tools, notably including IfcConvert (an application to convert IFC models to other formats), Bonsai (an add-on to Blender providing a graphical IFC authoring platform), and many other libraries, CLI apps, and more. Support is also provided for auxiliary standards such as BCF and IDS.
For more information, see:
Development is sponsored through your generous donations!
Contents
| Name | Description | License | Service |
|---|---|---|---|
| bcf | Library to read and write BCF-XML and query OpenCDE BCF-API modules | LGPL-3.0-or-later | |
| bonsai | Add-on to Blender providing a graphical native IFC authoring platform | GPL-3.0-or-later | |
| bsdd | Library to query the bSDD API | LGPL-3.0-or-later | |
| ifc2ca | Utility to convert IFC structural analysis models to Code_Aster | LGPL-3.0-or-later | |
| ifc4d | Convert to and from IFC and project management software | LGPL-3.0-or-later | |
| ifc5d | Report and optimise cost information from IFC | LGPL-3.0-or-later | |
| ifcbimtester | Wrapper for Gherkin based unit testing for IFC models | LGPL-3.0-or-later | |
| ifcblender | Historic Blender IFC import add-on | LGPL-3.0-or-later* | |
| ifccityjson | Convert CityJSON to IFC | LGPL-3.0-or-later | |
| ifcclash | Clash detection library and CLI app | LGPL-3.0-or-later | |
| ifcconvert | CLI app to convert IFC to many other formats | LGPL-3.0-or-later* | |
| ifccsv | Library and CLI app to export and import schedules from IFC | LGPL-3.0-or-later | |
| ifcdiff | Compare changes between IFC models | LGPL-3.0-or-later | |
| ifcedit | CLI wrapper for ifcopenshell.api IFC model mutation functions | LGPL-3.0-or-later | |
| ifcfm | Extract IFC data for FM handover requirements | LGPL-3.0-or-later | |
| ifcmax | Historic extension for IFC support in 3DS Max | LGPL-3.0-or-later* | |
| ifcmcp | MCP server for querying and editing IFC building models | LGPL-3.0-or-later | |
| ifcopenshell-python | Python library for IFC manipulation | LGPL-3.0-or-later* | |
| ifcpatch | Utility to run pre-packaged scripts to manipulate IFCs | LGPL-3.0-or-later | |
| ifcquery | CLI tool for querying and inspecting IFC building models | LGPL-3.0-or-later | |
| ifcsverchok | Blender Add-on for visual node programming with IFC | GPL-3.0-or-later | |
| ifctester | Library, CLI and webapp for IDS model auditing | LGPL-3.0-or-later |
The IfcOpenShell C++ codebase is split into multiple interal libraries:
| Name | Description | License |
|---|---|---|
| ifcgeom | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcgeom_schema_agnostic | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcgeomserver | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcjni | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcparse | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| ifcwrap | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| qtviewer | Internal library for IfcOpenShell | LGPL-3.0-or-later* |
| serializers | Internal library for IfcOpenShell | LGPL-3.0-or-later* |