Petru Conduraru 53881c4888 ifcgeom: salvage subtractions when OCCT refuses invalid boolean operands
When BOPAlgo refuses a cut wholesale (BOPAlgo_AlertBOPNotAllowed), for
example because one of the subtraction operands is an open shell rather
than a closed volume, all subtractions were previously discarded and the
unclipped first operand was used (GEO152). Archicad models with
degenerate clipping volumes (issue 2320) lose all wall clippings this
way, since a single defective operand voids the good ones too.

Instead, retry the operation with only the trustworthy operands:
uniformly 3-dimensional, BRepCheck-valid and with positive volume. For
the defective ones, first attempt to reconstruct a proper volume from
their faces with BOPAlgo_MakerVolume, mirroring what --make-volume does
for first operands. Invalid but 3-dimensional operands are also
excluded, because inverted solids have been observed to classify the
complete first operand as interior, silently emptying the result.

The retried result passes through all existing acceptance gates
unchanged (shape healing, BRepCheck, manifoldness, interference checks
and the fuzziness retry ladder) plus a new gate specific to this path:
a subtraction may never gain volume relative to the first operand.
When every retry fails, behaviour is exactly as before: the first
operand is used unmodified.

On the issue 2320 storey, 28 of 31 previously unclipped elements now
receive valid, strictly material-removing cuts; the remaining 3 fall
back to the previous behaviour.

Generated with the assistance of an AI coding tool.
2026-07-25 08:34:39 +03:00
2026-07-24 16:15:54 +05:00
2025-12-19 18:53:14 +05:00
2025-12-19 18:53:14 +05:00
2026-01-26 17:10:03 +05:00
2026-07-24 15:43:59 +05:00
2026-04-26 21:29:16 +02:00
2026-01-26 17:10:02 +05:00
2026-02-18 09:09:46 +11:00
2025-08-28 20:05:45 +02:00
2025-08-28 20:05:45 +02:00
2026-07-22 18:47:44 +05:00
2026-04-13 19:40:25 +05:00

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!

Open Collective Contributors

Contents

Name Description License Service
bcf Library to read and write BCF-XML and query OpenCDE BCF-API modules LGPL-3.0-or-later PyPI Anaconda-Server Badge
bonsai Add-on to Blender providing a graphical native IFC authoring platform GPL-3.0-or-later Official GitHub Unstable Chocolatey
bsdd Library to query the bSDD API LGPL-3.0-or-later PyPI
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 PyPI
ifc5d Report and optimise cost information from IFC LGPL-3.0-or-later PyPI
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 PyPI
ifcclash Clash detection library and CLI app LGPL-3.0-or-later PyPI
ifcconvert CLI app to convert IFC to many other formats LGPL-3.0-or-later* Official GitHub
ifccsv Library and CLI app to export and import schedules from IFC LGPL-3.0-or-later PyPI
ifcdiff Compare changes between IFC models LGPL-3.0-or-later PyPI
ifcedit CLI wrapper for ifcopenshell.api IFC model mutation functions LGPL-3.0-or-later PyPI
ifcfm Extract IFC data for FM handover requirements LGPL-3.0-or-later PyPI
ifcmax Historic extension for IFC support in 3DS Max LGPL-3.0-or-later* Official
ifcmcp MCP server for querying and editing IFC building models LGPL-3.0-or-later PyPI
ifcopenshell-python Python library for IFC manipulation LGPL-3.0-or-later* Official GitHub PyPI Anaconda Anaconda Docker AUR AUR Unstable Pyodide WASM Wheels tag
ifcpatch Utility to run pre-packaged scripts to manipulate IFCs LGPL-3.0-or-later PyPI
ifcquery CLI tool for querying and inspecting IFC building models LGPL-3.0-or-later PyPI
ifcsverchok Blender Add-on for visual node programming with IFC GPL-3.0-or-later GitHub
ifctester Library, CLI and webapp for IDS model auditing LGPL-3.0-or-later PyPI

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*
S
Description
No description provided
Readme 506 MiB
Languages
C++ 57.4%
Python 36.2%
C 3.9%
Gherkin 0.7%
JavaScript 0.3%
Other 1.3%