Infraworks automatically splits imported topography

[jaronkDDX26]

I have this topography that was split using arcgis and imported as a tiff. For some reason when I import them individually Infraworks would split up the topography. But when I select a group of them and import them as one file, they are automatically joined. Is there a setting or ability to disable this? I need to export my model and it keeps the topography split when exported, I need them to be kept as separate data sources.

[Karsten.Saenger]

Hi @jaronkDDX26 ,

I'm not sure if I fully understood what you are doing.

You have Tiff elevation files and load them separately. That results in split terrain?

When you load the raster data sources all in one selection, it's not split?

But later you want to export the model (to what file format?) and keep the terrain split?

Can you please clarify the workflow?
What InfraWork version do you use? Do you place all raster files on the terrain layer, so that they are merged into one single terrain?

Regards,

Karsten.

[jaronkDDX26]

You are correct with how I'm importing the terrain. When I import them as individual data sources they have a gap between them, but when I select all of them to import as a single data source, there's no gap. I want to be able to export the model with the terrain as separate data sources as an fbx., but when exported the gap is still there in between the terrain meshes.

My workflow right now is generating heightmaps from Arcgis and exporting them as tiffs. They're tiled and in a grid over an area which is why I need to keep them separate. Then I'm trying to import them as the topography into my Infraworks model. In the end I would need to be able to export the Infraworks model as an fbx. 

I am current working with Infraworks 2019 but I won't upgrade to the newest version right now.

[Karsten.Saenger]

Hi @jaronkDDX26 ,

thanks for the additional information.

Can you double check and see if you have terrain layers available in the Layers list?
These have been introduced with one of the 2019.x updates - more info at InfraWorks Help: Surface Layers

If the layers are there but you haven't moved all of your Tiff data sources to the terrain layer - it could be an explanation for the seam lines.

Regards,

Karsten.

[jaronkDDX26]

They're currently under ground surface. 

[Karsten.Saenger]

Hi @jaronkDDX26 ,

ok - then I don't have an explanation in the moment.

It could be a program issue that has been fixed in a newer version. Is it possible to share the three Tiff files so I can test on my system with version 2021?

Regards,

Karsten.

[jaronkDDX26]

Here are the heightmaps

[Karsten.Saenger · Accepted solution]

Hi @jaronkDDX26 ,

thanks for sharing the files. I think I have an explanation, but not an easy solution.

I loaded one TIFF into a new InfraWorks model, then added the other two TIFF files. I put all on the terrain layer in InfraWorks.

There are seamlines for all three TIFFs, so it doesn't make a difference if I load more raster files at once or raster by raster:

A second test in Civil 3D - TIFF's as FDO connection and you get the same result.

The explanation is most likely, that InfraWorks and Civil 3D read the raster files differently compared to ArcGIS.

There are different "allowed" was where to put the origin for each pixel in an image. It seems that one program puts it at a corner point, the other in the middle.

You can see that the gap is half a pixel in Civil 3D:

The solution is to make the tiles at least half a pixel larger so that you get an overlap along the borders. I can't say if that is easily possible in your workflow.

Another possible workaround - that worked in the past, but I don't know if ArcGIS supports it: Export points for each pixel -> create point cloud in Recap (Pro) - > create a surface terrain in InfraWorks from point cloud.

Regards,

Karsten.

[jaronkDDX26]

Thanks a lot for your time and help! Now I know the base problem and a some direction to try and solve this.