Breaklines

[patcloutier5765]

I'm trying to learn C3D 2008 and am hitting a few snags. Right now I have a surface created from a point file with contours and tin lines. I want to add breaklines around existing buildings, so the contours don't go through them. Can somebody please help?

[Anonymous]

PatCloutier wrote:
> I'm trying to learn C3D 2008 and am hitting a few snags. Right now I
> have a surface created from a point file with contours and tin lines.
> I want to add breaklines around existing buildings, so the contours
> don't go through them. Can somebody please help?

Sure, Pat.

Draw a polyline from node to node to node connecting where you want your
breakline to be. Under your surface definition in Prospector, right
click on breaklines, and add as proximity breaklines. Your surface
will automatically update.

--
Jason Hickey

Civil 3D 2008
Dell Precision M70
2 GIG RAM, 256 MB nVidia Quadro FX Go1400
Intel Centrino 2 gHz Processor

www.civil3d.com

[patcloutier5765]

When I do this the contour lines change, but still go through the building. I'm thinking this is because the survey points, taken at the corners of the buildings, that I'm using for my nodes are different elevations. Does the polyline have to be set at one elevation?

[patcloutier5765]

or is there a way to just trim the contour lines at the builing edge? do I have to explode the surface to do this?

[Anonymous]

PatCloutier wrote:
> or is there a way to just trim the contour lines at the builing edge?
> do I have to explode the surface to do this?

You explode your surface, you remove the dynamic link that any further
edits would have. In other words - "DON'T DO THAT"

Yes, the contours are going through the buildings because of varying
point elevations. How to stop it? Many ways - create a feature line
at the correct elevation (what's the correct elevation? That's for you
to determine) and add that feature line (with the same elevation at each
PVI) to the surface as a breakline. Or explore surface masks. Or,
if you're comfortable with holes in your surface, use a hide boundary on
the surface (warning - be prepared for inaccurate volume calcs.) Or
adjust the points so that they have the correct elevation (although the
surveyor may smack you on the head for this, unless you are the
surveyor, in which case your license gives you free reign over the
survey data.)

As you can see, there are numerous ways to accomplish your task. A
firm understanding of TIN modeling and the editing features of Civil 3D
will assist you in far more detail than I can/have.

--
Jason Hickey

Civil 3D 2008
Dell Precision M70
2 GIG RAM, 256 MB nVidia Quadro FX Go1400
Intel Centrino 2 gHz Processor

www.civil3d.com

[Anonymous]

You are talking about boundaries or masks, not neccessarily breaklines.

Create HIDE boundaries for every building you don't want the contours to go
through.

Surfaces, edit, add boundaries (in the toolspace)

Matt

[mpowelljr]

You all beat me to it... lol Message was edited by: mpowelljr

[patcloutier5765]

Thanks for the help. I went with the boundaries - hide and it worked. I've been fighting with this for a day and a half now, and the actual process took 10 seconds. Anyway, thanks again for the help.

Pat

[Civil3DReminders_com]

If your adventurous, you can try this also. Not quite sure if it affects the contour label text.

http://civil-3d.blogspot.com/2007/04/using-aecpolygon-to-hide-surface.html

Christopher
http://civil-3d.blogspot.com/

[Sinc]

If you have a lot of buildings, there's a routine in the SincpacC3D that lets you select them all and create hide boundaries for every building all at once. Buildings should be polylines, survey figures, or feature lines.

http://www.ejsurveying.com/sincpacc3d.htm

[Anonymous]

Nice tool.

Matt