Toposolids by csv are offset on global coordinates

[robertklaschka]

Using Revit 2025 I have been trying to create a toposolid from points in a csv file that have been digitised on OSGB36 (British national grid) I am using a revit file pre set-up to place the toposolid close to the internal origin but am getting a result that offsets the position of the toposolid from the coordinates that have been digitised.

I have attached the .csv file.

Below shows the digitised coordinates

And here in Revit the coordinates on the left reflect the highlighted coordinate above. So there appears to be an offset of roughly 19m West and 6m South from the cooridnates in the .csv file

I have also found that toposolid creation this way doesn't honour share coordinate rotation which is a bit of a disappointment.

In short it looks like toposolids don't play well with shared (global) coordinate systems which working in measured survey is a disappointment, because in many other ways they support topographic survey much better than their predecessor toposurfaces.

I can do a manual fix by offsetting, but this doesn't bode well for the wider use of toposolids for existing conditions.

[YorickSOHO]

Toposolid from csv is created using the "internal" coordinate system. Meaning origin is at "internal origin", x axis goes right on the screen and y axis goes up on the screen (north project ofc).
What I understand from what you provided is that because you have large values (which is what you get with usual geodesic coordinate systems) revit creates the toposolid "center to center". When creating the toposolid you should get a warning stating that it will be created where Revit wants but maybe your .ini file skips this warning.

To solve your problem, the only solution I found so far was to :

1. open the csv in excel
2. create two new columns for x and y
3. subtract revit project base point coordinates (assuming project base point is placed at internal origin) N/S to original y column and E/W to original x column
4. expand the formula across all rows
5. copy paste as value the calculated values to the first two column
6. delete the formula column
7. save as CSV
8. create the toposolid
9. copy angle to north value in project base point
10. rotate the create toposolid with project base point as rotation center using copied value

Or use dynamo/Revit API to do all this with a single button ..

[robertklaschka]

Yes pretty much what I have done. No warnings and no I haven't touched my ini. Thank you though, you've confirmed my own conculsions...

While I am tempted to accept this a solution its really a work around to a deficient implentation, another half finished tool for a full priced product.

[YorickSOHO]

I agree that a prompt asking for import by origin or shared coordinates wouldn't be so hard for Revit dev team to implement.
Maybe give this Idea a ton of votes : Toposurface from CSV/TXT - shared coordinates

P.S. : To complete the answer, this warning should appear when using "large" values : "Imported Toposurface Points are located a large distance from the model [...]" while creating site ...