algorithmic modeling for Rhino


I am new to Gismo and having a problem getting it to working. I tried running the analyse_terrain example and it produced the following error in the generate terrain script:-

Runtime error (TypeErrorException): iteration over non-sequence of type NoneType

line 966, in createElevationContours, "<string>"
line 984, in title_scalingRotating, "<string>"
line 1084, in script

Do you have any idea what I am doing wrong?



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Replies to This Discussion

Hi Patrick,
Would it be possible to attach the .gh file? Then we can immediately identify what is the issue.


 Thanks for the quick response!

 I used the analyse_terrain example you provide and both give the same error message with generate terrain 1. "Solution exception:iteration over non-sequence of type NoneType" which seems to follow from the error message from the python.



Hi Patrick,

Thank you for the attached file.
When I run your .gh file on Rhino 6 SR21 I get no errors.
Here is the result showing generated terrain and its terrain analysis and the second photo is flow paths analysis on top of it:

Are you using Rhino 7?
I wonder if it has something to do with tolerances?
Can you set the Rhino units to 'Meters' with 'Absolute Model tolerance': 0.01? Like this:

Hi Djordje,

 I made this change to the tolerances with no impact on the error. Yes, I am using Rhino 7,  I was trying this morning to check in 6 but cannot as I just purchased 7 licenses and my 3-month trial with 6 expired just. 


Okay. The problem is that I don't own Rhino 7 at the moment to replicate this error.
Try this: set the 'numOfContours_' input of the "Terrain Generator" component to '0'.


 That fixed the issue! The output terrains are shown below. Which seems the same as the one you posted! So when I build my own model I should set this input parameter numOfContours_' 0.


Thank you


Hi Patrick,
I am glad it helped.
Yes, for now you will have to have no contour curves on your terrains. Until I figure what is the issue with the Rhino 7.
If you really need them, you can also create these contour curves with regular Grasshopper components:

Create one vertical line from top to the bottom centroid of the terrain brep/mesh bounding box. Then divide that line (that's 'numOfContours_' input) by some number. Position the XY planes at those division points, and then just intersect the terrain brep/mesh with those XY planes. The result of intersection are contour curves.

Hi Djordje,

 Thanks for the help getting things up and running. This is a supper help apps and so impressed by the speed at which this was sorted out!

Thank you


Good to hear that. If any other issue arise, please do not hesitate to open a new topic, or post it here. I am eager to know about the different behavior that may come up in Rhino 7.
Have a nice week.






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