algorithmic modeling for Rhino

Obscure Components Vol. 1 - Combine Data And Sift Pattern

Hi all

After some 5 years of hard work with Grasshopper I stuck myself to think:

"Damm it, I always use the same 10 components for most of my works!"

Even if this is perfectly normal, I decided to ask the help of the forum (your help :-) ) to extend my knowledge of Grasshopper and data management.

For my first post in this series, I would like to collect some examples or hints about COLLECT DATA and SIFT PATTERN.

Thanks to everyone would like to share his/her secrets!



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Replies to This Discussion

Shift Pattern I used it a few times, for example, the algorithm of offset curve with variable distance, the method depends on the type of curve (polyline, polycurve, curve, line...) and with this component you can on each output have a specific type of curve, to then give the appropriate method of offset.
The other component I hardly ever used, but it seems the opposite in some way.

thanks for your hints. I make the definition of your example for download.

But this variable offset distance do you mean something in Grasshopper or is one of your components/cluster?


The Sift+Combine pattern is designed to mimic conditional clauses (i.e. 'if statements'). It allows you to pull apart a stream of data, operate on subsets of that stream and then put it all back together again in the same order.


You can also create a flag field out of your list of conditions. This way if I add more conditions (to the merge component) I only have to add new outputs to the sift pattern component.

[Combine] and [Sift] also maintain <null> data items which is useful for maintaining tree structures and as placeholders. Can't think up a good example to illustrate this at the moment, but you can see it happening in Daniel's screen grab.

Thank you guys.

All very helpful






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