Petru Conduraru 8665725eb6 IfcGeom: make permissive-shape-reuse folding style and instance aware
The permissive-shape-reuse task fold collapsed tasks onto the innermost
single-child taxonomy node. Three defects followed from that.

1. When the shared representation had a single item, the fold descended
   past the representation collection down to the raw geometry item, and
   Converter::create_brep_for_representation_and_product later failed
   with 'RepresentationIdentifier not found' on every folded product,
   aborting the conversion. The public AC20-FZK-Haus model fails to
   convert entirely with these settings.

2. Styles attached to traversed wrapper collections, such as an
   IfcStyledItem on an IfcMappedItem occurrence, were dropped, so folded
   occurrences lost their per-occurrence colours.

3. Folding was applied with use-world-coords enabled even though product
   placements are then baked into the shared geometry, which collapses
   all folded products onto the first product's placement. The regular
   grouping in mapping::reuse_ok_() already refuses reuse in that case.

The fold key is now the pair of the shared node and the effective hoisted
surface style, so occurrences with the same style share one processed
representation while differently styled occurrences keep their own, which
also covers styled IfcMappedItem occurrences from issue #143 that the
regular grouping must skip. Folded groups are rewrapped in a collection
carrying the hoisted style and the first folded task's representation
instance, and folding is skipped under use-world-coords.

Verified against IfcConvert glTF output on synthetic mapped-item models
(styled occurrences, non-identity mapping targets) and AC20-FZK-Haus:
world-space geometry and materials match the unfolded output exactly,
and default-settings output over the IFC4 test corpus is byte-identical.

Generated with the assistance of an AI coding tool.
2026-07-21 16:57:51 +03:00
2025-12-19 18:53:14 +05:00
2025-12-19 18:53:14 +05:00
2026-01-26 17:10:03 +05:00
2026-07-18 22:39:33 +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
2026-04-13 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
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