Subassembly Composer - API for start / end of horizontal curve?

[jimgi78okt]

Hi to everyone! I am trying to build a subassembly in SAC (C3d 2023) where the position of one of its points will vary depending on the horizontal alignment, i.e. have a variable offset (distance) from the origin.

To be more specific, this offset variation will take place inside the transition curve (spiral). So i would like to know the start and end chainage of my spiral.

I have looked the available API functions in SAC, but it doesn't seem to have something for this. Is there a way to achieve that? Thanks in advance!    

[Beka_Tchigladze]

@jimgi78okt 

Hello,

I don't think that there is an option to get spiral data in composer you have to try with regions or baseline chainage somehow what is the actual problem?

There is an option also to extract actual turn or if assembly is at the curve exactly.

https://knowledge.autodesk.com/support/civil-3d/learn-explore/caas/CloudHelp/cloudhelp/2021/ENU/Civi...

[ecfernandez]

Hi guys!

I agree with @Beka_Tchigladze, it might help if you get the turn direction because you will know if you are in a curve or tangent, and based on that make build your geometry. However, it depends on the complexity of the geometry you aim to create.

Best regards!

[jimgi78okt]

Thanks both! The thing is that i need to shift the subgrade's crown inside my spiral and not throughout the whole curve (i am dealing with a roadway project...). For example i would like to have it at the start of the spiral 2,5m to the right of the central axis, and at the end of the spiral 2,5m to the left of the central axis. I think i am going to over come it with feature lines and targets. I do not see any other way. Thanks anyway!

At a next version of autocad, it would be nice to have an interaction between subassembly composer and the alignment (through APIs e.g. giving data for the whole curve at which the station belongs and not only data for the current/specific station e.g. start/end of spirals and circular curves, the full superelevation/cant of the curve, radius at the curve etc.). Basically this would boost the engineering capabilities of the software!

[ecfernandez]

Hi @jimgi78okt, pretty nice to know you thought of a solution. Regarding your comments, I think they are really good also. You can create with them an "idea" you can share with the Autodesk team. Remember you can post your ideas for the enhancement of the software here:

Link: Civil 3D Ideas 

Best regards!

[jimgi78okt]

Thanks @ecfernandez . Did that! Hope someday this becomes real!