Road Template Layer

[ColC]

I am having trouble retaining information in The Road Template Layer. Some of the data is being deleted by another unkown operation/function. I suspect it could be when I run contour/triang and the erase previous contour entities.
When I have different .rdn files in the same job it is impossible to retain the data I need. I have to re-run the road network to get the data back. This is made more difficult if I used the road breakline data elsewhere. If I copy the road breakline data to another layer that data was also being deleted. I found the solution was to construct polylines from the road breaklines by using polyline follow.

Is there a flag Ican set to stop this problem?

[gskelhorn]

ColC, Carlson adds information to entities as extended data (XData). It then uses this data to identify what it should delete. If you want to prevent the automatic deletion of some entities then use command XXDATA being menu File | Drawing Utilities | Remove XData.

Hope it helps...

[ColC]

Thanks, I will give that a try

[ColC]

There is very limited information available for this Xxdata function. I need to know what are the connections that cause the deleting. In some situations I may be happy to delete items others less so. Is there somewhere I can see what stands to be deleted and what function will delete the entity.

With Road Networks, I have created my design, traced some of the polylines and worked away on various operations then turned my road breaklines layer back on and 80% has gone.

[gskelhorn]

Command XXDATA will remove extended entity data (XDATA) from an entity, not the entity.

Carlson attaches information to entities in XDATA. The Carlson routines then use the XDATA to provide the intelligence (links to source data / creation command etc.). When you process a Road Network design the routine erases the entities it created previously, creates new entities and tags them with XDATA. This would include the TIN, contours, 3D polyline breaklines, etc. whatever is configured to be drawn.

If you copy entities created by a Carlson routine the XDATA is considered part of the entity and is also copied so the copy has the same XDATA. This means if a Carlson routine is going to delete the entities identified by matching XDATA then both the original and copy are deleted.

If you want to prevent the copy from being managed by Carlson then you can use command XXDATA to remove the XDATA.

If you want to see what XDATA is attached to an entity use the command EDITEDATA.

[ColC]

Thank you for taking the time to reply.
I discovered that copying polylines that were part of the Road Network were being deleted. I got around this by Using 3d polylines, follow, therby creating a new entity with the same data. My problem has been that the original Road network is being deleted without me running Road Networks. I would have run Cont from Tin and I would have selected delete current surface. That was a problem also, because it did not delete the current surface info. But I suspect it did delete some of the Road Network polylines.

Are there other operations besides Road Network & Contour/Triang which are creating the exdata?

While I have been typing I have been trying the editedata. I found some interesting unwanted links with some of my contours. The contours were indicating links to entirely unrelated jobs/tins. More work for Leonid!

I appreciate your feedback, all the information you provided was not available from manuals.

[gskelhorn]

Hi ColC. Short answer: Yes there are definitely many other routines making use of XDATA. F2F, LotNet, Lot File, DRAWPROF, DRAWSCT, etc...

If you are using triangulation and contouring routines (or the Surface Manager) on a surface created by RoadNet there is a very good chance you will lose the breaklines created by RoadNet.

<opinion>
As you mention, the design and behavioural intent of the software is not documented so it is not possible to know beforehand. You really have to test a workflow before trying to rely on it. Any deviations or alterations to the established workflow need to be tested. And to be honest, I find it important to fully test a workflow after an update before I feel comfortable. The documentation for changes in each update (minor or major) is rather sparse.
</opinion>

[ColC]

Thanks for your feedback.
Yes I could not agree more, testing is essential before confidence some be gained in the software. Your information has opened up an aspect I was previously in the dark.