Grasshopper change 0.9 to 1.0

Hi, there must be changed a lot with the new grasshopper. I had a good working model mostly with trigonometrical functions. But it seems the order, how curves and points are counted and indexed has changed? Some insights?

Best Jan

I really can’t tell from that image. The file looks pretty complicated so I doubt I’d be able to give you an answer even if I had the file without first spending a day digging through it.

Can you narrow it down to a specific component, or small group of components?

The possible explanations are:

  • There’s a bug in Grasshopper 1.0 making it behave differently from 0.9
  • There’s a bug in Rhino 6.0 making it behave differently form 5.0
  • You were relying on data being provided in a specific way which was never guaranteed, and a subsequent change to an algorithm (typically due to performance optimisations) changed its behaviour without breaking the contract.

This digging you described, is what I will do now, I only wanted to know if there where some major changes. There is not much documentation about this. I think this is a grasshopper bug. I will post my findings.

Thank you


I checked, it seems that taking a geometry and taking the brep edges and sorting out as a list is changing the index. So I had to chance the domain to get the right line.

Best Jan

Hi @JHA I reported it a few months ago, but without success. BUG - SURFACE TO CURVE @DavidRutten this could be fixed please.
thanks Erick.

I sorted all brep edges by hand to rescue the model, and again in the updated version 1.0.0007, everything is broken again. This sucks really. Sorry to say, but if I have to go through the gh files again and again to fix them.

best Jan

Hi Jan -
Perhaps this post helps explaining what’s going on:


Hi Wim,
thank you very much, I think this video addresses exactly my case! I was switching computers all the time and of course one time this occurred as I switched the version of grasshopper.

Best Jan