If you move a wall, and that wall has features (e.g. openings), it's desirable to also move those openings (because they are invisible). This is a special exception to `should_transform_children` because the definition of the feature (opening) is inherently tied to the parent (wall). What wasn't considered is that this would typically then also move subchildren of the features (e.g. fills like doors). I'm surprised nobody caught this earlier. I did also consider another approach where if you move a wall, it moves all unfilled openings, and if you move a door which fills a opening, it moves the opening too. Intuitively it sounds nice, but it doesn't work because: - Openings can have multiple fillings. If you move all fillings, they all fight to move the openings. - All logic about children goes one way: a placement may have child placements relative to it. This breaks the convention (if moving a door instead moves its opening) which can make brains explode. - It starts to conflate rules about relative / referenced placements with spatial decomposition. We assume all IFCs are valid and follows the convention of relative placement but we cannot guarantee this. This also leads to brain explosion.
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:
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Contents
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* |