Generative design export not able to create history

[Anonymous]

Hi,

I've already tried 2 times to export a result of a generative design study and, although the results are correct, I need to modify some parts of them. To do so, I need to go back in the history to the organic form, but I can't as the only thing I have is the base form. 

I've seen some posts in the forum talking about this but I haven't found a solution. Is there?

[Ben-Weiss · Accepted solution]

Hi @Anonymous ,

Good question! Normally, when you export a generative outcome for an organic shape*, you see a design history consisting of two base features (preserves & obstacles), a T-Spline Form, a Boundary Fill, and a Combine:

And every once in a while you see only a base feature (this is what I think you are seeing):

Converting a generative outcome back to a parametric design is tricky business. Most of the time we get it right, but sometimes the system chokes on the geometry for any of a variety of reasons. In these cases, we use a fallback method that creates only a single base feature (without a full design history). It's not perfect, but it's better than a complete failure without any usable geometry at all. Sometimes this happens due to some subtle aspect of the generative setup you created, other times it's hard to pin down a cause.

In summary, you didn't do anything wrong, and unfortunately there's no easy way to "fix it" and get back to an editable T-Spline feature.

Hope that helps,

Ben

* You get a different parametric recipe for some manufacturing constraints (2-axis cutting and 2.5-axis milling) which make geometry with sketch/extrude instead of T-Splines.

[Anonymous]

That makes sense as I recognise the structure generated is one of the most complex things I have ever done. 

Thanks!

[Ben-Weiss]

I'm glad I was able to clarify what's going on, even if I can't get you back that design history!

Ben