Dion Moult a4f2075c3d ifcviewer: x-ray marquee selects through occluders
Box select resolved hits by reading the depth-tested object_id MRT, so only
the front-most surface in each pixel could ever come back. In x-ray that is
wrong twice over: you can see the geometry behind, and you still cannot
select it.

Add a second box-pick path used only while x-ray is active. It runs the same
vs_pick geometry through fs_boxpick with depth compare Always, no depth write
and no colour targets, scissored to the marquee — so nothing culls a fragment
behind another and the pass's only output is an atomicOr of one bit per
object into a hit bitmask. Reading that back gives every object with geometry
inside the box, occluded or not.

The bitmask rides alongside sel_flags at group(0) binding 2, allocated and
bound by ensureSelectionFlagsBuffer so the two can never disagree about how
many object ids exist. The layout entry is FRAGMENT-visible only: WebGPU
forbids a read_write storage buffer in the vertex stage, and every pipeline
shares this layout. Back-face culling is off for the pass — a box landing
inside a closed solid would otherwise see none of its faces and miss it.

Outside x-ray the depth-tested read stands, so a plain marquee still takes
only what is visible. A failure to build the pipeline falls back to that path
rather than breaking box select.

Tests cover the three properties worth having: x-ray selects strictly more,
its result is a superset of the plain one (a bare count would wave through a
wrong scissor or an off-by-one in the bit decode), and turning x-ray off
restores front-most-only. They need a model with real self-occlusion, which
sidecar_bake cannot currently produce — it segfaults on any input, including
the pristine sample.ifc — so they skip with an explanation until a fixture is
supplied. See the note at the top of the spec.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-07-30 07:46:22 +10:00
2025-12-19 18:53:14 +05:00
2026-07-20 10:46:20 +10:00
2026-01-26 17:10:03 +05:00
2026-07-22 19:01:49 +05:00
2026-05-18 19:24:25 +02:00
2023-09-14 09:29:20 +02:00
2026-02-18 09:09:46 +11:00
2026-05-08 16:20:26 +02:00
2026-05-08 16:20:26 +02:00
2026-05-08 16:20:26 +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*
serializers Internal library for IfcOpenShell LGPL-3.0-or-later*
S
Description
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Readme 487 MiB
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C++ 57.4%
Python 36.2%
C 3.9%
Gherkin 0.7%
JavaScript 0.3%
Other 1.3%