IfcPatch#

IfcPatch is both a CLI utility and library that lets you run a predetermined modification on an IFC file, known as a patch recipe. This is great for running prepackaged scripts on IFC models on a server with a standardised interface. It’s also great for distributing little scripts that need to modify an IFC to users who don’t know how to code or aren’t interested in knowing the details.

Source installation#

  1. Install IfcOpenShell

  2. Clone the source code.

  3. cd /path/to/src/ifcpatch

Here is a minimal example of how to use IfcPatch as a Python module or CLI utility:

$ python -m ifcpatch -h

usage: __main__.py [-h] -i INPUT [-o OUTPUT] -r RECIPE [-l LOG]
                   [-a ARGUMENTS [ARGUMENTS ...]]

Patches IFC files to fix badly formatted data

optional arguments:
  -h, --help            show this help message and exit
  -i INPUT, --input INPUT
                        The IFC file to patch
  -o OUTPUT, --output OUTPUT
                        The output file to save the patched IFC
  -r RECIPE, --recipe RECIPE
                        Name of the recipe to use when patching
  -l LOG, --log LOG     Specify a log file
  -a ARGUMENTS [ARGUMENTS ...], --arguments ARGUMENTS [ARGUMENTS ...]
                        Specify custom arguments to the patch recipe

Exactly how it is run depends on the recipe. A recipe may require zero or more arguments which are specific to the recipe. Here’s an example which runs the ExtractElements recipe, which, as the same suggests, extracts out elements. This recipe expects one argument, which uses the IFC Query syntax. In this example, we’ll extract out all IfcWall elements.

$ ifcpatch -i input.ifc -o output.ifc -r ExtractElements -a "IfcWall"
$ cat output.ifc

Here is a minimal example of how to use IfcPatch as a library:

import ifcpatch

output = ifcpatch.execute({
    "input": "input.ifc",
    "file": ifcopenshell.open("input.ifc"),
    "recipe": "ExtractElements",
    "arguments": ["IfcWall"],
})
ifcpatch.write(output, "output.ifc")

You can also alias it to a command:

$ alias ifcpatch='python -m ifcpatch'

Alternatively, you can package it as an executable.

$ python make.py
$ ./dist/ifcpatch

Patch recipes#

You can view all built-in patches in IfcPatch here: List of IfcPatch recipes.