Comment by koolala
Any there any open CAD file formats that lay a foundation for describing this kind of 3D data without classic triangles?
Any there any open CAD file formats that lay a foundation for describing this kind of 3D data without classic triangles?
A .step or .stp file encodes the model as mathematical shapes, rather than approximating it with polygons, but it doesn't save the entire parametric workflow or history, only the final result. As far as I know, there is no widely adopted file format that also saves this information.
For architecture, there is Industry Foundation Classes (IFC). IFC is a standard for describing building. FreeCAD supports this natively. There's a tutorial here: https://yorik.uncreated.net/?blog%2F2025%2F002-nativeifc-tut...
Blender has and extension for IFC called Bonsai. https://extensions.blender.org/add-ons/bonsai/
Parent's comparison is pretty great, but it shouldn't be "overdone". It's not really the format that's different/a problem (it's not hard to make a blender object from a CAD design - the same way an SVG can be rendered to PNG, and similarly irreversible in both cases), it's the whole design flow.
CAD uses geometry primitives with parameters and exact sizing (e.g. you draw a rectangle of this size, and cut a whole into it this and this offset from one of the corners, and you expand this shape to 3D). As mentioned this can be approximated via geometry nodes, but they are very different in "ideology".