XML Export missing ROT for Curve data

[brettHF455]

I use Civil 3d to create surfaces for grading that I export to Leica Machine Control.  XML files are the easiest means to do this.  When Civil3d exports and xml with a curve it does not include the ROT value.  From what I can find on the XML 1.2 formatting for curves this is a required attribute.  With the missing I get an error on import. 

If I open the file by other programs such as XML notepad or Carlson Land XML it also shows this an error but will continue to load file.  The Leica software will not load the file and needs to be corrected.  For surfaces the only fix I have found is exploding the surface twice and saving as a DXF then I can load and use the surface this way, but fairly time consuming.

I haven't been able to find a fix for this or anyone else having this problem.

Thanks for any help.

[rl_jackson]

Forgive me for being dense here but what is ROT?

Also, I would not expect a surface to export any curve data, a surface does not have curves. I have also had issues with Leica Infinity/Smartworx reading XML files, and attributed it to a Leica issue, having bumped into so many. 

[brettHF455]

ROT defines if the curve is cw or ccw.  You are correct in that the surface does not have curve data, but if the surface was created with feature lines with curves these are included in the xml under plan features.

I did some more digging and found this out, if an alignment is exported in xml the curve data in it will contain a ROT value, but feature lines exported will not.  I have attached a file that has both in it.  The curves under Plan Features  do not contain a ROT value but the curves under the Alignment  do.  If opened in xml notepad these can be seen.

[rl_jackson]

I would say there is a valid reason for that.

As an alignment the arc is planar there's no deviation in elevation so ROT would apply in that case. With a FL you have a "elliptical arc" (I use that term lightly) that travels along a path from one Z to the tangent Z it's not really a arc in the same sense and is defined by the XYZ values provided and the radius, there's no "direction" as it's in multiple planes.

[brettHF455]

That makes sense, but the problem seems to be that Civil 3d exports curve data in a XML file that does not contain a ROT value which the XML standard shows as a required field.  So other software cannot use the data that is contained within the curve field of the file.

Wouldn't a FL with an elliptical arc still have either a cw or ccw curve unless it was completely vertical?