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A bit of FreeCAD BIM work

by Yorik on 09.08.2014 in freecad , opensource

This afternoon I did some BIM work in FreeCAD for a house project I'm doing with Ryan. We're using this as a test platform for IFC roundtripping between Revit and FreeCAD. So far the results are mixed, lots of information get lost on the way obviously, but on the other hand I'm secretly pretty happy to see FreeCAD capable of communicating fluently with Revit already.

We already identified many bottlenecks, a major one being how FreeCAD imports IFC files, it basically transforms everything into dumb solids, which, when exported back to IFC, become faceted Breps, which Revit treats as non-editable. FreeCAD's native Arch objects, on the other hand, are in most case built of standard extrusions, and therefore stay editable in Revit. Thomas from ifcopenshell, which is the IFC importer/exporter we use in FreeCAD, is also thinking about the problem, no doubt we'll come with a solution any day soon.

In the meantime, modeling directly in FreeCAD, although slow (way slower than I would do in Blender), is already pretty reliable (not a single crash, everything nicely undoable, modifiable, fixable, etc) and enjoyable (fairly easy to look at your model the way you want to see it). It's not something I do often, I prefer the speed of Blender to raise the geometry, then I use FreeCAD to turn it into serious stuff, but here I specifically wanted to use the native Arch objects.

The speed of the workflow is of course a delicate matter, that can't be solved overnight, but now that we reached a certain maturity and stability with the Arch module, it'll be the time to begin to study more efficient ways to use it.

by Yorik on 09.08.2014 in freecad , opensource