Convert Super Alignment to Super String - Null Points

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Darcy Richardson
Posts: 12
Joined: Mon Dec 09, 2019 12:10 pm

Convert Super Alignment to Super String - Null Points

Post by Darcy Richardson »

Hi all,
Has anyone had issues with converting superalignments to super strings, and sometimes getting null points appearing at the start or end? Vertex appears in a long section profile as “N/A, 0m”.
This is causing issues for us when we export to IFC via a chain, as Navisworks shows a line going down to -999.
I’ve tried playing with superalignment settings, and also with Filter functions, and I can’t seem to get rid of the null point after conversion (aside from manually deleting, which would interrupt our export chain).

Can anyone offer any help or suggestions? 12da file of one example of this is in the link below, with original SA and converted Super. String D.S0370.17.01.SS is the one showing the N/A null point.

[url]https://cardno1-my.sharepoint.com/:u:/g ... g?e=zuWCJh[/url]

Also worth noting, I was previously using version 14.0C2g and didn't have this issue as much, but have recently updated to C2j and have noticed it happening more frequently.

Cheers,
Darcy
Graeme Winfield
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Joined: Thu Nov 10, 2005 10:59 am
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Re: Convert Super Alignment to Super String - Null Points

Post by Graeme Winfield »

Hi Darcy

It may be that Navisworks does not allow for null points.

What would you like to do when a point doesn't have a height?
Richard Mitchell
Posts: 216
Joined: Tue Apr 22, 2014 11:52 am
Location: Melbourne

Re: Convert Super Alignment to Super String - Null Points

Post by Richard Mitchell »

Darcy, you could pop in a Delete panel with source box set to Filter. Use View or Model(s) etc to isolate and include Extents tab with tick box 'Process only selected vertices', to isolate you -999 data.
RMitchell
Arup
Darcy Richardson
Posts: 12
Joined: Mon Dec 09, 2019 12:10 pm

Re: Convert Super Alignment to Super String - Null Points

Post by Darcy Richardson »

The aim of this is to remove the null point from the string, and keep the rest of the string intact.
I've read the exported IFC file back into 12d afterwards, and it also shows the point trailing off to infinity, so it's not really a Navis issue.

Had a chat with Richard and tried a few things, but still haven't been able to get rid of the null value. We tried the Delete with filter that he suggested, but 12d doesn't seem to be fully able to identify/isolate a height of null. Also tried to convert to alignment first and then to super, but results in the same error.

Unfortunately it's also a bit unpredictable which strings it happens to and where. Sometimes it's the string start, sometimes end, and for some it's neither, which makes the suggestion of attribute manipulators a bit difficult as well.
Graeme Winfield
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Re: Convert Super Alignment to Super String - Null Points

Post by Graeme Winfield »

Darcy Richardson wrote: Thu Aug 25, 2022 5:39 pm The aim of this is to remove the null point from the string, and keep the rest of the string intact.
Do you want to remove the horizontal as well?
(For all null heights, delete horizontal point)

Or, for all null heights make it zero or another height?

Note, a super alignment has separate horizontal and vertical geometry. They can start and finish at different locations.
When a super alignment with partial vertical is converted to a super string, the points without a height get the null value.

I was told that usBIM software can work with null values in the IFC.
https://cloud.usbim.com/
Darcy Richardson
Posts: 12
Joined: Mon Dec 09, 2019 12:10 pm

Re: Convert Super Alignment to Super String - Null Points

Post by Darcy Richardson »

Thanks Graeme, I think there's something in that, about the SA geometry, it only seems to happen when we've got a superalignment referencing another superalignment, must be a very minor disconnect in there with the conversion function.
I've also got one simple SA that I converted, and it has N/A points on every vertex. But strangely IFC Export/Navis doesn't seem to have an issue if it's in the middle of the string, only when it's on the first/last vertex.
Darcy Richardson
Posts: 12
Joined: Mon Dec 09, 2019 12:10 pm

Re: Convert Super Alignment to Super String - Null Points

Post by Darcy Richardson »

In any case, we've managed to work out a process with a bit of help from Richard, the process ended up being:
- Use 'Utilities > A-G > Convert > Convert' to convert superalignments to super strings
- Use 'Utilities > H-Z > Null heights > Null to height' to change null heights to -999
- Use 'Utilities > A-G > Delete', and the filter selection Extents tab (with "process only selected vertices" ticked), to delete heights between min -1000 and max -998. Deletes the whole vertex, both horizontal and vertical.

Also noting that the Delete function wouldn't work in the export chain if we captured the step using type Option-Manual, only works if using the Option type.

Thanks everyone for your help!
Phil Davies
Posts: 876
Joined: Mon Jun 27, 2016 2:14 pm

Re: Convert Super Alignment to Super String - Null Points

Post by Phil Davies »

I am pretty sure you don't need the Null to Height step, I thought you could just type in null as your maximum Z value and it would find it.
Phil Davies
Spatial Data Manager
GMC Surveying
Phil.Davies@GMCSurveying.com
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