Issue with Curves on Surface often not Extending in 2024.1

[amandaallsion.lila]

Hello.

I have noticed a consistent issue in 2024/2024.1 where curves on surface will not extend the same as in previous versions. It seems about 4 or 5 times more often that I am experiencing a "fail" when trimming a surface and asking it to extend a COS to create a boundary. A re-project does not help. In these cases, I have to duplicate the curve on surface, and extend the CURVE, and reproject the extended curve, in order to create a successful trim boundary. This did happen in previous versions, but it's MUCH MORE common now.

I am able to duplicate this issue between 2024.1 and earlier versions of 2022.1 and 2022.2 consistently. The curve that is not extending is made from a projection of the adjacent templated surface. If you delete the curve on surface, untemplate that adjacent surface and reproject it in both 2024.1 and in 2022, you should also see it calculates the curve differently, and will extend in 2022, but not 2024.1. The issue happens with both view projection and normal projection methods. I am not sure if this is an issue with the original projection, or the way it is calculating the extension.

I did also try intersecting the adjacent surface. (by extending the templated surface, and trimming it back to its shorter form, then intersecting that), and that WILL extend in 2024.1. Perhaps this may be what lead to some of the “higher math” and warped trim converts I have been experiencing? If there is something unusual with the project tool, it could cause a cascading effect of surface issues down the line. I'm on the hunt for other examples to share, but hopefully this will be a clue to at least something that may be happening.

I have an image attached showing the COS I am trying to extend and tried to attach a wire file as well. It says the wire file is not supported?? Why is it that I cannot attach a WIRE file to an Alias forum? I have shared the file directly with GG. If there is a better place/way for me to share the wire file, please let me know.

Thanks!

[KaiTi.L]

@amandaallsion.lila thanks for pointing this out. I will investigate
You can attach a wire file by zipping the file.

[amandaallsion.lila]

Thank you, KaiTi! Please see my response below with the attached file. I accidentally responded to myself here, but cannot find a way to delete this post.

[amandaallsion.lila]

Thank you very much, KaiTi! I have attached the zipped Alias file.

I also have an example of how a projected curve on surface is worse in 2024.1 than in 2022, which seems related to me. (The resultant surface built is worse in 2024 from the same projected curve.) But it was suggested to me to make individual posts rather than one with many things, so in case it is a separate issue, I will post elsewhere.

[amandaallsion.lila]

Please let me know if you are able to duplicate this issue. I just tried it again, and can confirm the issue is still happening even after a reboot. I can reproject the curve in each version, and it will extend in 2022-2.1 and will not extend in 2024.1.

[KaiTi.L · Accepted solution]

@amandaallsion.lila thanks for your detailed explanation and the attached wire file. I was able to reproduce the mentioned issue. I created a ticket: ALS-27162 CoS does not extend as expected.

Best regards
Kai