Splitting merged contour lines (mesh)

[Anonymous]

I have received a DWG with contour lines for a terrain. Unfortunately, two contour lines intersect and is regarded as a closed polygon by ArchiCad. That means that when I now want to change the mesh point height of one of these contour lines (selecting a point and clicking "Apply to All"), it selects and changes both contour lines ... This results in me having to go through each and every point in the two contour lines and elevate each point manually. Quite a painful task as I am dealing with approx 800 points in each!

Is there any way in ArchiCad to split one contour line into two?

Essentially we are just talking about splitting up a polygon/mesh.

P.S. If the terms are wrong or confusing do tell me, and I can try to reword or explain more, perhaps using some screenshots or simplified example.

[Anonymous]

I don't think you can find in nature contour lines (lines with equal elevation) that intersect each other because they lie on parallel planes perpendicular to the Z vector (vector of gravity). Maybe the one line is a boundary line or ridge or constraint that just follows the terrain. I have made two videos on how to model properly a terrain. The one shows how to make excavation pits, plateau, how to cut contour lines that are already applied on terrain, how to calculate cut and fill volumes and schedule them. The other one shows how to make a river, how to make the banks and the water body. You can look up in YouTube under Archicad excavation and archicad river.

For your case you should dinstinguish which are the contours, finish the natural ground with these, and after you finished, you can apply the other lines that can follow the terrain ("All Ridges" selection).

[Anonymous]

laszlonagy wrote:
What if you cut a small hole around the intersection of the two ridge lines, then delete the hole? That will definitely separate the two ridge lines from each other as it will result in 3 ridge line segments.

Genius Laszlo. Thanks!