Hi all, Is it possible to use Grasshopper to delete some objects in Rhino? I have filtered some curves in Grasshopper, and I want to delete the curves in the Rhino model.
Thanks
Delete Crvs outside a boundary.gh (19.4 KB)
I’ll leave the Python to someone else but can suggest a better way to filter the curves that are “outside a Boundary”:
Delete Crvs outside a boundary_2025Jun5a.gh (21.5 KB)
If you want to ignore curves that touch the boundary, that would be different?
P.S. Like this:
Delete Crvs outside a boundary_2025Jun5b.gh (24.7 KB)
Using area center points doesn’t work.
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yes, thanks Joseph, what I want to do is to select the crvs outside boundary and not intersect with the boundary, then I what to select them and delete these crvs in Rhino
Right, but in order to delete Rhino curves, you need to have a Rhino file with that geometry.
I thought R8 might be able to do that without Python. But no GH file 
I can’t learn from images alone. (especially of icons 
)
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I think I have somehow achieve it in Rhino7…but the rs.Deleteobjects() is a bit problematic…it will cause Grasshopper popup quite a few banners. Maybe the Cache/Purge component you use can avoid it?
These components were added in Rhino 8. I’m using Rhino 9 WIP
In the past I used this script:
import rhinoscriptsyntax as rs
import scriptcontext as sc
import Rhino
sc.doc = Rhino.RhinoDoc.ActiveDoc
if id and delete==1: rs.DeleteObject(id)
sc.doc = ghdoc
delete_by_id_python.gh (7.1 KB)
PS: the python script is updated for Rhino 8
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Thanks for posting the R8 files. Even with them, I find R8 difficult to understand for several reasons that you have gotten used to by now, I adapted them to my code; had to hide the layers to see my colors.
Delete Crvs outside a boundary_2025Jun5c.3dm (55.6 KB)
Delete Crvs outside a boundary_2025Jun5cc.gh (26.0 KB) (UPDATED to “Purge”)
Hey, it doesn’t work 
Crap, I don’t like R8. (LATER: fixed in version ‘cc’)
For R7, you probably want Python to delete the curves.
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Of course not, how would I know since your GH file was set to “Push”, not “Purge”.
It works now, thanks again.
Struggling to adapt the Python you posted but don’t know how it was “updated for Rhino 8”
With great knowledge comes responsibility for sharing it effectively. 
You know what. I might have misunderstood your comment but just to be sure… I deleted my posts above.
Oh NO Something got lost in translation. I will repost my version ‘c’ above with credit to you for showing us the R8 way.
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I got an extent query on this topic…
For the curves intersect with the boundary rectangle, how can I just keep the parts inside the boundary? I wonder if we can achieve it in grasshopper, or we can only do it within Rhino?
To do it manually in Rhino, I have to split the curves that intersect with boundary rectangle, then pick the curves one by one that are outside the boundary, then delete.
make a planar surface with the rectangle and use ‘Surface|Curve’ physical intersection
Cool, that is a clever way!! Why I didn’t think about that…
Many thanks Kyuubimode~
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You might try Trim with Region.
Without posting a GH file (with internalized curves), I won’t do it for you.
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Yes trim with region will be faster if you know its always going to be a region without holes (which is what you have shown).
I have been using regions with holes in some current projects I defaulted to the Surface|Curve intersection because of that.