Grasshopper change 0.9 to 1.0

[JHA (Jan)]

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

[DavidRutten]

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.

[JHA (Jan)]

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

Jan

[JHA (Jan)]

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

[ErickVasquez (Erick Vásquez)]

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

[JHA (Jan)]

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

[wim (Wim Dekeyser)]

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

Geometry on Shapediver is different from the Rhino

This is a common problem where a list order varies from computer to computer or between Grasshopper version as the tolerances and other factors may have affected the order of your lists. In order to keep the order stable and predictable, you have to create a geometrical or mathematical check and sort the list accordingly. More in this tutorial or video below:

-wim

[JHA (Jan)]

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

[ThomasE (Thomas Evans)]

Hi @wim what do you think about this? Does the same thing happen on your computers?
@pavol @edsahergom

Keep Rhino 5, or upgrade to Rhino 6?

thank you @dan Going deeper into this, it happens when you pass a Brep to a curve parameter, the vertices order goes back by 1. This issue started in Rhino 6 and continue in Rhino 7. [SharedScreenshot] CURVE_bug_te.gh (14.3 KB)