Revit > Rhino - Column baselines

Hi all,

When sending Revit columns to Rhino, it seems that it is sending the “Analytical Column” baseline rather than the BIM baseline? If there are structural walls with analytical model in Revit turned on, Revit automatically shifts the wall and column baselines to line up.


When sending the Revit to Rhino, the column baselines are all offset accordingly, but I thought it should be the BIM element baseline being sent rather than the analytical model baseline? We can fix it by turning off the analytical model for the adjacent walls which is fine for this instance but may not be ok in other cases.


Is it working as intended, by sending the Analytical baseline rather than BIM model element baseline?

Thanks

George

Appreciate if anyone from Speckle devs can advise

Hey @George , apologies, this slipped through :sweat_smile:
@connor from our team is the best one to reply to this question, he’ll be back early next week!

In the meantime, we’d love to hear a bit more if you can share about your specific use case, as we’re trying to make Speckle more useful for structural workflows.

I’m also curious as to why the analytical lines are diverging from the BIM ones, is this common / good modeling practice? I would have assumed not, but I don’t have experience here :slight_smile:

Hi,

just wanted to write the exact same as the original author of this thread…

I am a bit confused as to why Speckle would send the analytical model (the base line) of a Structural Column if you are not specifically deciding to send the Analytical Column (category)? Is there a reason for this decision?

Usually there shouldn´t be much of a difference, but there might be due to not paying attention or bad modelling practice… I think it should be at least an option to send the BIM base line!

Cheers

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I will build up on this one, as we stumbled upon it too. If one wants to analyze the baselines, for example, to deconstruct geometry or to evaluate those lines, the results would not be right. We have implied on our side too, that the baseline of Speckle is according to the baseline of Revit.

Would be interesting to know the background of it. It would really help us, if it would be the actual Revit baseline.

Thanks and all the best,
Alex

CC: @bjoern, @samberger, @ltascheva

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and we are using the baseline for this one:
01 Column Eccentricity Example · BollingerGrohmann/SPKL-BG-SpecklePY-LIB Wiki (github.com)

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Yes, please change that! If you want to use the analytical column base lines you can just receive those separately, right?

@connor: Regarding this topic, we are always happy for a brief chat/vico

Sorry for no response as we had to push on with our workaround to meet deadlines etc, but it seems there are many users interested in the topic.

Our specific use case: We are sending the revit model to rhino to build the structural analysis model. The structural model generally does not perfectly match the BIM model / structural layout by necessity of simplification / assumptions etc.

We’d prefer to have control over the rationalisation of the BIM model into a structural model rather than adopting the logic chosen by autodesk in their ‘analytical model’ by being able to send the BIM baseline. It would also benefit parties that wish to send the actual BIM model to grasshopper for other design activities/post-processing/whatever. As mentioned our workaround was to turn off the ‘analytical model’ in Revit to avoid speckle choosing the autodesk-defined structure model from being exported to Rhino

It would be beneficial if Speckle could send both a) the actual BIM baseline of elements or b) the revit analytical model baselines so that users can choose which item they actually need.

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Thanks for the description - we have noted the distinction.

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Hi everyone, thanks again for bringing this to our attention!

We have updated the logic to use the BIM baselines instead, changes will be shipped in 2.14 :slight_smile:
See: Fix(Revit) : Send BIM base line instead of analytical baseline by connorivy · Pull Request #2535 · specklesystems/speckle-sharp · GitHub

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