Drawing lines and points from a specific DAT/ txt file

[ivanov.chv460899]

Hi everybody,

Many times in my practice we receive a 3d design from an external design company in different formats. The most common one is the XML format, but that one is not always giving the best result. I talking about designs with many different layers, slopes...
The result surface from the import of XML file is basically only points and Civil is deciding how to make the triangulation.
That is why we ask for DAT file. Most of the times it is an export option in the microstation or 3Dmax I am not sure about.
That file is consisted by points and lines defined with E, N, Z and an extra forth column with the numbers 1 or 0. I think that is an old format also used for plotters - 1 is pen down, 0 is pen up.

I have lisp which can import that coordinates as a 3D plyline, but then is a real challenge to filter the break lines from the points.

I have some experience with lisp and I tried to write one by my self, but I am sucked at the moment where the line number from the file should be saved, line or 3dpoly command executed and then continue from the last used line till the end of the file.

Any routine which will read and import the points and lines correctly will help me a lot.

If anybody finds that a challenging and interesting I will highly appreciate any ideas and suggestions .

Two examples of that .dat file and txt are attached.