ArchiCAD and Civil 3D

[Anonymous]

Hi everyone,

I'm a draftsman at a surveying company working with Autodesk Civil 3D, and we have a handful of clients using ArchiCAD. I'm working with one at the moment to get our 3D surface from Civil into ArchiCAD.

We've tried exporting the points to an .xyz file, but the only problem is that when that gets bought into ArchiCAD there are no breaklines like there would be in Civil 3D. Is there anyway to bring in the 3D faces from Civil, or to bring in the breaklines from Civil 3D?

[Barry Kelly]

What do you mean by "break lines"?
Are you referring to contour levels?

Can you show a screen shot from Civil 3D of what you want to see?

Barry.

[Anonymous]

Barry wrote:
What do you mean by "break lines"?
Are you referring to contour levels?

Can you show a screen shot from Civil 3D of what you want to see?

Barry.

Thanks Barry.

In Civil 3D, breaklines are parts of the surface that helps dictate which points on the surface to join.

For example, if you had a brick wall with spot heights taken on either side of it, the each side of the wall would act as a breakline stopping the spot heights on either side from joining.

The 3D Faces I've got would reflect the breaklines, so if there is someway to bring those in, it would be the easiest way.

I've attached a screenshot illustrating what I mean.

[Barry Kelly]

commanderjarak wrote:
I've attached a screenshot illustrating what I mean.

No image attached.

If your 3D form is correct in Civil 3D then it should appear the same in Archicad.
Possibly you might need to add (magic wand) your own ridges (contours) onto the mesh in Archicad.
Then you will have the option to display the 'User Defined Ridges' so you don't see all the triangulation lines.

Barry.

[Paul King]

Hi Barry - that is not quite correct - breaklines ensure mesh triangles do not span across defined vertical steps in the terrain, but merely abutt one another at differents heights on either side of the break, so as to reflect a vertical step (for example along a retaining wall) . This is something that xyz point data import in ArchiCAD simply cannot handle with the current implementation. A long standing ArchiCAD problem, forcing painful time consuming workarounds and manual kluging.

See my post here for an example: https://archicad-talk.graphisoft.com/viewtopic.php?p=280995#p280994

[Anonymous]

I have this same issue and it is a major want. If this was solved, we could kick smart BIM information back and forth between us and civil, landscape and surveying and greatly streamline our process. This is the key to true BIM intelligence on the site level.

[Laszlo Nagy]

I think that break line information gets lost when the Terrain is saved as XYZ files, since an XYZ files is just a huge collection of points that define a surface, but with no added intelligence about the exact composition of that surface.

You could try to save the Terrain as IFC file and bring that into ARCHICAD. Try to save it from Civil 3D with the BREP (boundary representation) option (should be available among IFC Export settings), which guarantees correct reproduction of 3D surfaces and bodies. Then import or merge the IFC file into your ARCHICAD Project File.

[Barry Kelly]

The Civil cad model may be correct and the XYZ file may be technically correct.
The problem may be that in Archicad, a mesh can not have a vertical face (except for the sides of the mesh).

Bringing it in as an IFC BREP form should work although I can't say for sure as I have never tried it.
BREP should keep the exact form and create an object (NURB) of it in Archicad (unless I have that all wrong).

Barry.

[Nader Belal]

Sorry that I came late, but I think I have some ideas that may work.

Continuing to what was said by @Barry Kelly, you have these options:
1. Take points before and after the break lines, but near to it.
2. Import the XYZ file into ArchiCAD (don't make any changes just yet even if it means that the model is not correct).
3. Create a new layer with the same name where the mesh is located, but with an extension of .hid (for hidden)
4. Create a morph (or any other geometrical body) that by SEO (solid element operations) would give you the correct operation.

The other way is, in case that you don't need the mesh volume, create a hole in the mesh.

[Paul King]

I guess with SEO you can eventually, with a lot of backwards and forwards, emulate the appearance of what other platforms can do without effort - but this runs counter to efficient workflows, and makes auto contour line generation to follow dynamic mesh sculpting, and two way iterative information flows with civil engineer difficult.