Best workflow to convert "dumb" GDL objects into parametric ones

[til0byte]

Hi everyone,

I'm looking for advice on the best workflow to convert existing "dumb" GDL objects (non-parametric, static geometry) into fully parametric objects – ideally with some degree of automation.

Specifically I have two related questions:

1. Geometry extraction Is there a reliable way to extract the base geometry information from an existing dumb object programmatically? I'm aware of the "Save Selection as Object" approach which generates a GDL script with VERT, EDGE, PGON data – but is there an API-based method to extract this geometry data more cleanly, for example via the Archicad API? Ideally I'd want the raw geometry (vertices, faces, transformation) in a structured format rather than having to parse a generated GDL script.

2. Converting to parametric Once the geometry is available, what is the recommended workflow to turn it into a proper parametric object? Any pointers to documentation, tools, or workflows would be greatly appreciated. Thanks!

[runxel]

1. Yes, afaik there is an API function which gives you access to the primitives.

2. Hmmm 🤨 While you can use primitives in GDL it's not really a nice thing to do – users e.g. are accustomed to have the possibility to set the "resolution" of the generated 3D model. It's obviously much easier to let Archicad handle that, instead of trying to deliver a custom solution that subdivides on the fly.

So in my honest opinion the data soup you got out in (1) is trash and won't really be usable.

I really don't see a way for automation here either. With just primitives given it is impossible to figure out what surfaces/edges should be dynamic or static.

But I guess it also depends on the objects.  A table will be easier than an ornamented chair, etc.

[Laszlo Nagy]

This is not really an answer, more like an info: BricsCAD has a function called PARAMETRIZE, which does exactly that, I think they use AI to do it.

Hopefully, an adventurous developer creates something similar for Archicad soon 😀 :