randomly closed and opened curves from a solid

Hi,

I have this topographic geometry which i want to simply contour it and then the extrude them to show how these layers will be placed on each other.

the problem is, i cannot get closed curves. some of them are closed and some of them are open. i tried to check everything but there was nothing strange about the model itself.
if there will be a way to close the curves or even to know why these curves randomly get closed or opened, i can do the job. but unfortunately i couldn't find out the problem or solve it...

Attachments:

Topo Conturs2.gh, 6.8 MB

Replies to This Discussion

Permalink Reply by Joseph Oster on August 22, 2017 at 8:51am

If you flatten the input to the 'Join' just prior to 'Contour', the results will be different. In other cases, 'Join' was (also) doing nothing. Use panels to look at the output of each component to make sure you know what is happening at each step along the way.

Attachments:

TopoConturs2_2017Aug22a.gh, 6.8 MB

Permalink Reply by Joseph Oster on August 22, 2017 at 12:37pm

Contour distance = 20, with and without 'Cap Holes' - notice an important difference?

'Cap' is covering over a hole in the terrain!

I took two steps to rectify that:

used 'Boundary Surfaces' to get one or more surfaces per contour line.
added the expression "-x" to 'F' input of 'Z', so 'Extrude' goes down instead of up.