AutoCAD Civil 3D General Discussion

AutoCAD Civil 3D General Discussion

Reply
*Expert Elite*
BrianHailey
Posts: 2,850
Registered: ‎04-27-2005
Message 1 of 11 (2,146 Views)

Non-Destructive Breakline - What's it used for?

2146 Views, 10 Replies
11-07-2012 04:30 PM

When adding data to a surface, there is the option to add it as a "Non-destructive" breakline. 

 

http://screencast.com/t/qBnciKzR3i

 

What is this good for? I created a surface, copied it, and created a volume surface between the two of them. As expected, the resultant volume was 0.

 

I then draw a 3d polyline and snapped to elevations on the surface. I then took that 3d polyline and moved it up 5'. I then added that breakline to the surface as a "Non-destructive" breakline and the resultant volume between the original surface and the one modified with the new breakline was still 0. Absolutely no change was made to the actual surface, it just added additional triangles. 

 

Anyone have any idea why anyone would ever use such a thing? I'm trying to find a reason it's even option and I'm coming up blank. There has to be SOME reason it's there.

Brian Hailey
CAD-1.com
My Blog
*Expert Elite*
mathewk
Posts: 2,768
Registered: ‎07-09-2003
Message 2 of 11 (2,135 Views)

Re: Non-Destructive Breakline - What's it used for?

11-07-2012 07:25 PM in reply to: BrianHailey
I have never found a good reason to use non-destructive breaklines. However, when defining surface hide boundaries, I will use non-destructive often. This "trims" the TIN lines (by adding new verticies) instead of removing them. Essentially, when you use them for breaklines, you get new vertices when your breakline crosses a TIN line. Again, I"ve found no good use for them as breaklines.
Matt Kolberg
Cansel - Autodesk Division
http://www.cansel.ca/
*Expert Elite*
sboon
Posts: 2,204
Registered: ‎11-08-2005
Message 3 of 11 (2,127 Views)

Re: Non-Destructive Breakline - What's it used for?

11-07-2012 10:50 PM in reply to: mathewk

I've used them rarely, but there have been a few times when I needed to preserve the existing TIN either inside or outside of a closed area before adding new data to the surface.  A non-destructive breakline is useful for that purpose.

*Expert Elite*
neilyj
Posts: 3,926
Registered: ‎08-01-2008
Message 4 of 11 (2,123 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 12:10 AM in reply to: BrianHailey

I suspect that the "non destructive" part (as sboon suggested) does what it says - it merely preserves the original TIN structure but with additrional TIN lines at where the non destructive breakline crosses the TIN.

 

From the help "....The elevation for each new point is extracted from the original surface triangle, therefore maintaining the integrity of the original surface..." so the line could have been raised 100 feet and it still wouldn't have affected the TIN

 

I also use them in the same way as mathewk and sboon do as I guess this is the intended use.

neilyj
(No connection with Autodesk other than using the products in the real world)


IDSP Premium 2015 (mainly Civil 3D 2015 UKIE & Infraworks with some limited 3ds Max Design)
Win 7 Pro x64, 500Gb SSD, 1Tb HDD
32Gb Ram Intel Xeon CPU E5-2650 v2 @ 2.6GHz (32 CPUs), ~2.6GHz
NVIDIA Quadro K4000, Dual 27" Monitor, Dell T5610
*Expert Elite*
antoniovinci
Posts: 1,750
Registered: ‎06-03-2011
Message 5 of 11 (2,114 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 01:21 AM in reply to: BrianHailey

I would define a "non-destructive Breakline" as a "projected contour" added to the surface definition.

It does NOT affect the curvature of the C3D surface, just adding triangles to it. 

*Expert Elite*
Neilw
Posts: 2,322
Registered: ‎09-04-2006
Message 6 of 11 (2,068 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 08:11 AM in reply to: antoniovinci

So what is the purpose of these things? In the context of breaklines (not boundaries) I can't see any use for them either. A breakline that doesn't influence the surface isn't really a breakline in my thinking.

Neil Wilson (a.k.a. neilw)
Infrastructure Suite/C3D 2013, LDT 2004, Power Civil v8i SS1
WIN 7 64 PRO
HP Pavillion h8xt, i7 2600, 12 GB
RADEON 6450, 1 GB
http://www.sec-landmgt.com
*Expert Elite*
troma
Posts: 2,524
Registered: ‎05-21-2008
Message 7 of 11 (2,061 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 08:32 AM in reply to: Neilw

Neil, I think Steve got it.  You can use it to create a breakline on the existing surface before you perform edits on one side of it.  If you paste a surface onto a larger one, for example, C3D will triangulate from the edge of the surface you paste in, to the nearest data on the larger surface.  If you were to add a non-destructive breakline first you can control where that match point will be.

I had never looked at these, never used them.  But I have used feature lines to do something similar: draw feature line, elevations from surface (add verticies), add feature line back into surface to make sure that it doesn't change at this point, while I edit nearby.  Non-destructive breaklines look like a better way to go for that.

 

This is why I love coming here: always new ideas floating around.  (New to me anyway.)


Credit where credit is due! Give kudos or accept as solution whenever you can.

*Expert Elite*
Neilw
Posts: 2,322
Registered: ‎09-04-2006
Message 8 of 11 (2,055 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 08:52 AM in reply to: troma

Ok I get it now. I assumed it ALWAYS maintained the triangulation of the TIN, but after running some tests I see that it's position in the surface definition is a factor. Good to know.

Neil Wilson (a.k.a. neilw)
Infrastructure Suite/C3D 2013, LDT 2004, Power Civil v8i SS1
WIN 7 64 PRO
HP Pavillion h8xt, i7 2600, 12 GB
RADEON 6450, 1 GB
http://www.sec-landmgt.com
*Expert Elite*
AllenJessup
Posts: 6,100
Registered: ‎05-21-2003
Message 9 of 11 (2,022 Views)

Re: Non-Destructive Breakline - What's it used for?

11-08-2012 12:35 PM in reply to: troma

That sounds about right. I think I've seen post that describe exactly what you're talking about. Thanks for figuring it out.

 

Allen

New Member
dbrownsurvey
Posts: 2
Registered: ‎01-03-2014
Message 10 of 11 (1,077 Views)

Re: Non-Destructive Breakline - What's it used for?

01-03-2014 12:06 PM in reply to: BrianHailey

I have an design surface and also have multiple surveyed existing ground surfaces that need to be pasted into the design surface for quantity calculations. I can't figure out how to hold the integrity of the design surface outside of these little existing ground surfaces. Outside of all my existing ground surfaces, the tin lines are interpolated to the next design tin line instead of keeping the design surface elevation. I've tried the non-destructive breakline approach and maybe I'm doing something wrong, i don't know. Any help would be appreciated.

 

thanks

Post to the Community

Have questions about Autodesk products? Ask the community.

New Post
Announcements
Are You Going To Be @ AU 2014? Feel free to drop by our AU topic post and share your plans, plug a class that you're teaching, or simply check out who else from the community might be in attendance. Ohh and don't forgot to stop by the Autodesk Help | Learn | Collaborate booths in the Exhibit Hall and meet our community team if you get a chance!