Get outline (region) of points

Hello @all,
i have a bunch of points and some gridlines…
i want to get the outline of the whole geometry and cut the lines with the region…
does someone has an idea of how to get there? :slight_smile:

thanks in advance

Upload a file.

oh yes - sure
internalised (9.7 KB)

i need something like this :smiley:

okay, i got this one on my own

i patched the points to a surface, splitted it by the curves… and filtered the list to get the final result ^^

next time please categorize your topic accordingly that people not familiar with grasshopper dont waste their time making suggestions which are not applicable to you

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Hi @Kevin_Scholtyssek,

Just use the Boundary Surfaces component and then cast the output to a Curve.

Graph Space:

Model Space:

Patch and Split Surface are fine and all but they can get quite computationally intensive depending on the inputs.





@michaelvollrath by what magic did you get this to work?

@michaelvollrath oh okay :smiley: thats a lot better - thanks!

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I don’t know if it has been exposed in vanilla Grasshopper yet, but the Curve.CreateBooleanRegions method seems perfectly suited for solving this problem: (11.8 KB)

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FWIW, one can use Curve.CreateBooleanRegions for these cases too: (5.4 KB)


Thank you. I appreciate that the .CreateBooleanRegions works, but I still do not understand the difference between the examples I was testing and what the OP posted that makes Boundary Surface work on his curves and not mine.

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it`s a wild guess, but maybe it depends on how the curves are sorted?

It’s hard to say without a file to study/debug. But either way, when there’s a native RhinoCommon method that does exactly what the problem requires (I think), why not just use that method instead of hacky workarounds :wink:

I do not think that this is the case since the order doesn’t matter if the curves do not extend past their intersection points in the corners, but I will try.

Mostly because I am not familiar enough with coding that I would have been able to use the RhinoCommon method without having an experienced individual like yourself simply providing me with the finished component. In other words, that this a problem for beginning and non-programming Grasshopper users.

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That’s fair. Maybe try posting the file and we can have a look.

I will have to recreate the file. Please give me a moment.

Boundary Surface Test on intersecting Curves with internal (10.7 KB)
While the curves are internalized, I created them on the basis of Rhino geometry to make sure that the last set has knots that lie on the same corner points.

so i think it might have something to do with the “extented curves”…
give the boundary node just the segments of the closed curve of the object and it will work - but not for the pentagon in this example :smiley:

Because the circle is not centered on the pentagon. But still, it is not a solution for a grid of lines that do not have a convex envelope (imagine a U-shape)