I had a look at your data. There are a lot of places with vertices within 1-2 mm.
Pretty much everywhere it is magenta in this screen shot.

I couldn't always find linework that is close to those clusters. How did you create that surface, via site improvements or take off? I don't have a licence for the later.
It's a bit unclear why there are that many clusters with closeby vertices and also, there are a lot of tiny spikes in your surface, which are most likely the main issue for the machine output error.
That prevents it from being a one macro task since my DTM cleanup tool combines/average closeby vertices if they fall within a certain threshold. It would combine the vertices at the bottom of the spike and maybe the ones at the top as well, but the spike would persist and retriangulate occasionally across the road to some other vertices.


As you can see from the red color, those spike are created from breaklines, computed by the site improvement? That's the reason we can't use the built-in Flatten Surface. You'd have to untick "include breaklines" and that would cause some of the near vertical steps to disappear as well.

So, I have to utilize another one of my macros. I export the surface as DWG, which converts it to 3D Faces. I then bring it either back into the same project or an empty one.
Now I have separate triangles which I can test for their area.

We'll lose a few triangles on those vertical steps, but there should be enough information left to be retriangulated.
The new surface created from those remaining 3D-faces does actually export to SVD, so I assume those vertical spikes were the main issue.
But we can reduce the surface data by combining some of those closeby vertices with the second macro.
Original - 484014 triangles - 245090 vertices
spikes removed - 397144 triangles - 200470 vertices
vertices combined - 149308 triangles - 76380 vertices
I've uploaded the data to Dropbox, you'll get a separate mail for that.
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Ronny Schneider
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Original Message:
Sent: 05-03-2023 14:59
From: Ben Wall
Subject: Surface Export Error-Too Dense
Ronny,
Give me a sec and I'll email you directly.
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Ben Wall
Original Message:
Sent: 05-03-2023 14:11
From: Ronny Schneider
Subject: Surface Export Error-Too Dense
Is this happening while your surface has too many vertices close to each other (wihtin mm) and hence way more vertices/triangles that it actually needs?
Can you upload your surface here, or send me a private download link?
I've got a beta stage macro that combines closeby vertices in TTM's. I could run a test with it.
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Ronny Schneider
Original Message:
Sent: 05-02-2023 10:50
From: Ben Wall
Subject: Surface Export Error-Too Dense
I've created a grading model using a provided site xml that I've exploded and used as contours to create my Finished Design and FD with subgrades adjusted. However, when I try to export the machine control files I get the error that the surface is too dense. I can export the subgrade surface as an xml but when I try to export it as a svd I get the error. I've tried using the project cleanup to filter line vertices but the surface is made of lines and dots so it has not made a difference. Is there any other way short of abandoning my exploded information to get this surface to export? Maybe a way to convert a xml to svd?
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Ben Wall
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