Upfront.ezine : The Future of IFC Enabling Partial BIM Model Exchange

M by magicalcloud_75 on 7 Jun 2020, edited 10 Jun 2020 #

For reading IFC backgrounds

Enabling Partial IFC files, that will be the day!

https://www.upfrontezine.com/2020/06/upf-1058.html

M by Moult on 7 Jun 2020 # +1 votes

@magicalcloud_75 the BlenderBIM Add-on has the ability to:

Import only things which have changed
Import only a subset of the model
Import the entire model, excluding a portion of the model which you've filtered out
Export just a single object back into an IFC file without changing anything else

More partial IFC features are being built and polished :)

M by magicalcloud_75 on 8 Jun 2020 # +1 votes

That sounds great. Would be great to have some tutorials on that with some sample models. Can we arrange that?

M by Moult on 8 Jun 2020 #

@magicalcloud_75 I'm in the Sydney timezone so happy to organise any time to screenshare. A lot of my time is spent developing, so if there are any other power users out there who want to spend the time to deep-dive into these features, break them, and do video tutorials, I would welcome it :)

Y by yorik on 9 Jun 2020 #

Note that on the freecad side we also have already some ways to import parts of ifc files (the "IFC explorer" tool in the BIM workbench). The main difficulty is to figure out what you want to import, therefore you need to see the model, which takes some time to build.. In any case this is an interesting path to follow

M by Moult on 9 Jun 2020 #

@yorik by the way, not sure how much FreeCAD uses the geometry iterator in IfcOpenShell, but the iterator now has an includes/excludes argument to whitelist/blacklist elements to process :)

To solve the catch 22 I'm thinking of just showing a spatial tree and summary of elements for now. Have you had a chance to play with the IFC selector syntax?

Y by yorik on 10 Jun 2020 # +1 votes

@Moult I'm afraid I don't know anything of these two features yet... Tell me more! what's the geometry iterator? and the selector syntax?

Right now we have this IFC explorer tool in the BIM workbench, which builds a text-only, indented list of contents of an IFC file, and, optionally, builds a mesh representation too. That last operation is a bit slower, but there is much room for optimization I think.

Then you can pick the elements you want from the list, they are highlighted in the mesh model, and you can import only them.

Allowing to filter the list by type, name, property or whatever and fine-grain selection would be pretty useful, actually...