Export Super tins

[Sudheer Magapu]

How to export Super tins in XML format or any other format that is compatible with Civil3d ?

[Lee Gregory]

I don't think Civil 3D can support Super Tins.

[Graeme Winfield]

As Lee said, we are not aware of any other software have an object like a super tin.

I am not sure if a dwg output of a supertin is just the resulting triangles or something else.

[Fraser Hocks]

If you export a super tin to DWG or DXF it creates a set of 3D faces under the one layer that is essentially a singular tin. This should be readable by Civil3D, but will need some processing at the users end. As they use AECC objects (essentially a tin) which are a proprietary thing, so as far as I'm aware the only thing that can create / read them is Civil3D

[Richard Mitchell]

I am trying to create one export for Revizto using a supertin. The process I have so far is:

• Create faces from supertin (bigfoot licence with LiDAR data)

• Create new standard TIN using model from above

• Tick:
  • Weed tin
  • Triangle data
  • Colour by triangle data

• Create ifc file using standard TIN model

Supertin Mode is 'Replace' for all tins.

The issue I have is the resultant tin has triangle holes everywhere with the above settings even though it is quality 12d data and not some Bentley surface knock off from Open Roads.
The processing time when ticking 'Preserve strings' and removing 'Triangle data' pushes out to ~25 mins due to breakline checks which shouldn't be required when using triangle data. Now the completed tin looks good (no holes) but is set to the one colour, even though 'Colour by triangle data' is ticked. 'Weed tin' is auto selected when ticking 'Triangle data'

What should I be doing please? Going through all the options will take me the better part of 2hrs.
Could the Retriangulate Tin panel give an estimate of time based on radio button selections vs dataset using a base computer spec?

[Graeme Winfield]

Hi Richard

You can't turn a super tin into a standard tin, 99% to 100% of the time. They are not compatible. Fails at your 2nd step.

I am not surprised that "resultant tin has triangle holes everywhere".

Before there was a super tin, we manually created a merged tin.

Remember, a tin cannot have more than 1 height at the same x,y (vertical faces or caves). A tin in IFC land may have the same restriction.

[Richard Mitchell]

Thanks Graeme.
So my options are to either create boundaries and cut holes, which is not a simple process with shared tins, then export many tins to ifc. Or create boundaries and offset on the inside to trim the faces, add them to the retriangulate panel source.
The first option might create many sup trees in the properties box in Revizto which is also what I am trying to avoid.
I reckon exporting many tins to one ifc would work even if the same x,y has a different z as they are different entities. Any other solutions from your perspective?

[Richard Mitchell]

So Generate Trimeshes from 12d Objects works. Resultant ifc file is mega huge (2Gb in this instance).

[Sam Cech]

Generate Trimeshes from 12d Objects
is the only way I know to generate a Mesh for export to DWG/IFC that matches exactly the super tin

various macros have been tested in beta and I am not sure any actually work anywhere near 9/10 cases...

the issue with using super tin faces to generate a new tin is with the duplicate XY positions with different height
by default these clash and are weeded out, so if it works its an accident
the only way it could work would be to identify different tins by colour, shrink the edges by 0.1mm and that could retriangulate, a very complicated process.

[Lucien West]

With other software I have noticed, that when it combines tins it will adjust the the triangles of the first tin along the boundary of the second tin etc. I would say similar to nulling along the second tins boundaries, then triangulating across this gap. Maybe there is a way to get this to work in some automated way.

But maybe something like this has been tried.... I haven't so not sure what issues there would be.

various macros have been tested in beta and I am not sure any actually work anywhere near 9/10 cases...

[Alexander Cook]

This problem has been around for a long time.

In terms of a process to complete it with a macro, you would need to:
- Get the list of the tins in order
- Get the strings for the first tin
- Get the boundary of the second tin, offset it a small distance (ie 1mm) in and out.
- Drape the out boundary to the first tin
- Drape the in boundary to the second tin
- Fence the strings from the first tin by the boundary offset out.
- Fence the strings from the second tin by the boundary offset in.
- Combine the string sets and retriangulate
- Repeat, using the "merged" tin and strings as the first set, and the next tin in the order.

As far as a process, its not too complicated, there are little niggles, like dealing with holes, and knowing which way to offset a closed string to be "out".

By far the most complicated (and so far, insurmountable) tasks for me personally are:
- Creating a good algorithm for offsetting strings that will clean up all the loops, and check for bad polygons. (Non-jordan which happens to be Lee's favourite term)
- Getting the fencing to work neatly

I dare say that if anyone creates a program to complete all of that reliably, repeatably, and without taxing your CPU for large datasets, they will be very very popular