Prevent pipe breaks?

grasshopper
unhandled

(Thomas) #1

Hi,
I’m trying to create a brep pipe from a curve
I have tried the sweep- and pipe-component but both only gives parts of the pipe.
I have also tried to simplify the line but with no luck.
Does anyone have a universal solution to this problem or know why this is a problem at all? :slight_smile:


#2

Not without looking at your file.


(Thomas) #3

GH_script.gh (9.2 KB)

image


#4

Weird! You have a polyline with 906 segments, some of which fail to ‘Pipe’ properly. The curve is WAY FAR AWAY from the origin! Start point: {-72370.4, 139072.45, 0.95} Many of the segment vertices are not on the same plane.

Basically, I’d call it a “bad curve”.


(Ethan Gross) #5

Joseph, I really think David should add a “Keep your objects near the origin.” proviso to his “How to ask effective questions” There is no reason to expect someone who wishes to help to have to go on safari to find your geometry. I know sometimes this is an artifact of importing it from elsewhere but still, it adds one more layer of impenetrability.


(David Rutten) #6

I use Zoom On Preview if stuff is hard to find.

The curve is indeed pretty messy. The lengths of the individual segments are reasonably well distributed, so at least there are no super short segments.

However you could definitely clean this up by using a Simplify Curve component with an as large as possible absolute tolerance and angular tolerance setting. But even then there are some missing segments. I have to project the curve onto a single plane before simplifying to make it work everywhere.

I get the exact same problems btw. using the Rhino _Pipe command. Moving the curve to near the origin fixes some but not all problems. The problem as far as I can work out is that your segments are so short that near the sharp kinks more than one segment intersect:

I think the result you are after will require that the base curve is cleaned up significantly. Project and Simplify Curve may be part of this, but maybe you have to split the curve at all sharp kinks and either rebuild or just straight up linearise the segments in between all the kinks.


(Ethan Gross) #7

I use Rhino’s Zoom Extents but always feel more comfortable working with a grid visible. I guess it’s just a personal preference, although I don’t believe most of the people who submit such outlandish data are even aware of where it resides.


(David Rutten) #8

Incidentally the ridiculously long meshing times needed for the pipe geometry is clearly due to the shape being waaay out there. Move it closer to (0,0,0) and that part becomes much quicker. There is an outstanding bug report for this, I do not know when this will be fixed. (RH-37732)

GH_script_origin.gh (36.6 KB)


(Thomas) #9

Hi all,

Thanks for the replies

I have been away from GH for a looong time. I have obviously forgot some of the basic components - such as the simplify curve component … Simplify curve and the fillet component did the trick

Quick question: Does RH/GH have something similar to Revits “project base point”?


(Chris Hanley) #10

Quick question: Does RH/GH have something similar to Revits “project base point”?

I’ve recently been looking into this relationship, (I imagine your question might be along the same lines…working with imported geometry from “geo-refereced” drawings, Civil3D or something), and aligning them in Revit.
I think the short answer is…kind of. The Rhino drawings base point, (which technically can be set to anything), I think…corresponds to Revit’s project base point. This is not to say that the units/scale will be correct. It also doesn’t account for the relationship between Rhino’s Earth Anchor Point, and Revit’s Survey Point. I am literally working on a few examples of this today. Hopefully I will find a few more definitive answers. IMHO, This topic might be worthy of a new thread.