Corridor Transition Controls

[doni49]

I'd like to see some kind of transition control added in C3D.  One of the most common places that I used to use such controls (in InRoads at my previous job) was to transition between having NO ditch and having a ditch. 

InRoads had a "Transition Editor"  At every station that is between two different End Conditions, I could bring up the TE and it would show me the cross section view of each station in kind of an iso view.  I would ID a point in one section and connect it to a point on the next section.  In the ditch scenario I mentioned, I would connect the daylight point of the NO_ditch section to the daylight point of the ditch section and then I would connect the ditch bottom (both sides) and the ditch top to the NO_ditch section's daylight point.  The attached screen shot is two such cross sections with lines drawn (in red) showing how I'd like to connect them in transition.

By doing this, the feature lines get drawn correctly and the surface breaklines were correct. 

Another place this would be usefull is going from curb to no curb.  I can't put both assembly insertions at the same station because that messes up the surface.  But if I put a gap between them, there is a gap in the ETW feature line.

[fcernst]

Need a Daylight slope transition stations Tab on the Corridor Properties dialog box for transitioning daylight slopes in the longitudinal direction.

The Tab will show the Daylight subassemblies that are currently being used by the Corridor. The User will be able to enter (or pick) the Baseline station ranges the transitions will occur over. 

This should not be dependent on setting up Regions... In other words, no Regions would need to be created simply to execute the slope transitioning.

[joantopo]

In some software like Istram Ispol, for each region you specifies an assembly for the start station and another one for the end station, so for each station within the region, there is a transition between 2 assemblies.

In SAC, we can make transitions because we know the StartStation and EndStation of the Region, but it is very hard to do that for every subassembly.

[barrz84]

The amount of times I've had grief with this is lost on me! Why can we create a transition so simply in between gradings along the same feature line with one click however, we can't leave a desired gap in our corridor parameters as an empty region and simply transition between two regions?! There is no way to transition from one cross section to another over a desired length!! Even a simple kerb transition around a horizontal curve becomes impossible or fudged to get the model looking half correct!

[doni49]

I'm in agreement with you on this one.  If one region has a FL named "ETW" and then there is a gap but the next region down the line also has an FL named "ETW", it should just connect the two.  I think there should be an option to disable a region as there are sometimes valid reasons to have a blank region with no corridor info there.

[joantopo]

We can nake custom subassemblies with SAC ( BaseLine class) to do transitions in that subassembly in the selected region but it is not practical.

In Inroads or Istram Ispol you can choose the start assembly and end assembly for a region, so the region is composed by two assemblies, in the start and in the end and there is transition between them.

[peterfunkautodesk]

This is a great idea, but the timing isn’t quite right for development consideration in the near term. As such, it is being put on the back burner to be re-visited at a later date. Please continue to comment and add your support.

Regards,

Peter Funk

Sr. Product Manager

Autodesk, Inc.

[Dexterel]

To make transitions just use in your custom subassembly's this expression, but this is hard work to control correctly everything:

if(SA.IsLayout,CType(BLS,Double),
(-((CType(BLSE,Double)-CType(BLS,Double))/(Baseline.RegionEnd-Baseline.RegionStart)*(Baseline.Station-Baseline.RegionStart))+CType(BLS,Double))
)

Where:

BLS and BLSE types are double in this case (for example widths)

BLS represents start parameter

BLSE represents end parameter

This expression varies linear starting from BLS value and ends in BLSE value for start to end of an corridor region.

Check the red minus if you need it, depends on how you use this expression.

If you need the transition for a fix longitudinal length modify Baseline.RegionEnd and add a if() to check if you are over this value to use only BSLS

[joantopo]

It is very important for this feature, that the user can define a particular scenario.

Imagine that the Start Assembly has the code point: "AR2", but this code point doesn´t exist in the End Assembly.

Then, it would be interesting offer the possibility to the user, he can select a code point of the end subassembly to join to the code "AR2".

In fact, Istram Ispol has internally some criterias about this. 

Another scenario, was if the end assembly had 2 points with that code "AR2", if we want to select the nearest to the Baseline or the furthest.

[Dexterel]

I don't know the software you are referring to (Istram Ispol).

I don't like the idea that you can join inside a corridor two different codes.

Usually if a code exists in the beginning of a corridor region and dose not exist in region end, there is a reason for it (the point dose not exist).

You can create same FL styles for different codes and check in corridor properties "Connect extra points".

In civil you can control to join same codes Inward of outward. here it will be indeed nice to be able to select individual how to connect this points.

[javiermend]

start assembly-7 parts with diferents wide lanesFinish assembly-7 parts with diferents wide lines.

With regard to this question , is a pity that Autodesk don't take care about this question in the near term. It would be a clear competitive advantage that would put in equal conditions with others common software like Istram, Clip or Inroads.

It is not use to having diferent kind of assemblies between start and end regions with diferents number of layers and lanes.

In the photograhs, the finish assembly has 7 parts and the parts with number 2 and 3 has a symbollical wide such as 0.001m. In the star assembly this lanes has 3.2 m and 3.2m , so that the transition should be 3.2m to 0.001m.

Under my point of view if we employ coherence in the definition of the assembly, linear or parabolic transitions shouldn't be a programing problem for autodesk developpers, will it?

Thank you in advance.

Javier

[TimYarris]

Transitions are something we're considering as part of our initiative to make corridor modeling more efficient. Watch this space!

[Beka_Tchigladze]

when this feature will be implemented for 2023 version? or for 2035 version 😄

[doni49]

@Beka_Tchigladze 😂

[martin.folber]

Hi guys, as Civil 3D addicted. The ability to "map" corridor feature lines in transitions between two different assemblies is essential. Unfortunatelly, as it was mentioned...this is possible in competing products. The idea is generally here...

Thanks

Martin

[cmerrell85]

Any chance this is still on the roadmap?

[martin.folber]

Probably not... it is not on the public roadmap yet...

[TimYarris]

In recent versions, we added the ability to create transitions in the same subassembly (even across regions). What is still missing is the "connect the dots" between different subassemblies interaction that's shown earlier in this thread.

Autodesk Civil 3D Help | Corridor Transitions | Autodesk
https://help.autodesk.com/view/CIV3D/2025/ENU/?guid=GUID-FF0FC8DB-845F-47B5-92FD-6D226513BE34

[cmerrell85]

Yes, I'm aware of the corridor transitions feature but the graphic interface shown earlier in the thread would be extremely helpful. then we could do custom transitions from one subassembly to another. I've been using that tool and workflow in InRoads for over 10 years.

[doni49]

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@TimYarris  wrote:

What is still missing is the "connect the dots" between different subassemblies interaction that's shown earlier in this thread.

---

Is that part still "on the roadmap" for a future version?

[doni49]

@TimYarris  wrote:

What is still missing is the "connect the dots" between different subassemblies interaction that's shown earlier in this thread.

---

Is that part still "on the roadmap"?

EDIT:  I posted the comment above but it didn't show up so I thought I did something wrong and reposted it.