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by embedding-shape 106 days ago
How does OnShape handle that problem? The linked page seems to make the case that most CAD suffers from this, others just "hide" it better;

> This problem is not unique to FreeCAD. It is generally present in CAD software, but most other CAD software has heuristics to reduce the impact of the problem on users.
2 comments
throwup238 106 days ago
Most CAD software have a mapping algorithm that remaps the new features to the old features after a topological restructure using a combination of topological id systems and heuristics.

Solidworks and Onshape don’t “hide” it better, their algorithms are better and break down in much more complex models than FreeCAD. Each one also tends to have its own quirks so as you learn to use the software you get a bit of intuition on how to best model certain features to avoid angering the topological naming gods.

I don’t think I’ve ever seen Solidworks break down in a simple model, it’s always been in complex shapes using advanced features.

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DecoPerson 106 days ago
I think the word “solve” is better than “hide” here.

Fusion 360’s heuristics are so good that I rarely run into these problems. When I do, it’s usually because it was a drastic change to a previous feature in the timeline and I’m expecting to encounter issues because it’s a really fundamental change.

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obelisk79 106 days ago
that's basically because all commercial cad software are built on the same 3 geometric kernels (none of which are open source) and have robust and mature solutions. FreeCAD's is improving over time but it's a game of catch-up and the math and algorithms involved are complex.

The kernel FreeCAD uses doesn't really have a robust heuristic for this, so FreeCAD had to implement its own.

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