I’m not exactly sure why anyone would need to do this but I’ve seen it asked a couple of times in the last few weeks so I figured I would address it. Perhaps some other pieces of software can only accept point files. Whatever the reason, how do you extract the points from a surface to a point file? Well, it turns out that it’s a four step process. Display the points, extract the points, convert the points, export the points.
First, the surface needs to display points. A c0ouple options, create a new style that displays the points or edit the style the surface is using to display the points then, when you are done, change it back. In this example, I’m going to edit the style the surface is currently using. Select the surface, on the ribbon, expand out the surface properties pulldown, and choose Edit Surface Style. On the display tab of the surface style, toggle on the display of the points. It doesn’t really matter how they are displayed, just as long as they are displayed.
Next step is to extract the points from the surface. Again, use the ribbon. Select the surface and then on the ribbon, choose Extract Objects. Uncheck everything except the points and hit ok. This will create an AutoCAD point at every surface point. After you do this, you can change the style back to not displaying points if you want.
Now that there are AutoCAD points in the drawing, it’s time to convert them to Civil 3D points. Before you do this, make sure you point settings are set appropriately so you don’t have to hit enter for a description or name after each point is created. To speed things up, make sure your settings are as follows: Point Names – None, Point Description – Automatic or Automatic Object, Elevation – Automatic. On the Home tab, choose the points pulldown and then Convert AutoCAD Points. You now have Civil 3D Points in your drawing.
The final step is to export the points out to a file. If these are the only points in your file, you can export the All Points point group. If you have other points in the drawing, create a point group for just these points. Right click on the point group in the prospector and choose Export Points. In the export points dialog box, choose the point format and the file name and you’re done.
Hopefully someone will find this helpful.




March 23, 2010 at 5:36 am
Olá! Estou precisando de uma ajuda, eu fiz esse procedimento e deu certo agora eu gostaria de fazer outra coisa. Eu tenho varias linhas em 2D e quero jogar elas “casando” com a minha surface em 3D. Por favor se vocês puderem me ajudar e disponibilizar pra mim pelo e-mail ou algum link para eu aprender, ficarei muito grato!
Obrigado!
March 23, 2010 at 6:08 am
Translated via http://translate.google.com:
“Hello! I need a help, I did this procedure and it worked now I’d like to do something else. I have several lines in 2D and they want to play “wedding” with my surface in 3D. Please if you can help me and make me by e-mail or a link for me to learn, be very grateful!
Thank you!”
November 30, 2010 at 8:02 am
Thanks a lot for this information. This is very useful to generate the points of a surface after a “smoothing”, for example, instead of generating a “gridded” DEM.
December 4, 2010 at 10:27 am
I’m glad it’s helpful for you and let me know how well it works. I’m really interested in hearing how well or poorly my suggestions work.
April 13, 2011 at 6:24 am
Thanks so much for your post. It is really useful. I just wanted to add, (for those who are not too familiar with Civil 3d menus like me), that the “point settings” (mentioned in the fourht paragraph) are found in the prospector window at the settings tab>points>commands>create points>points creation.
If these settings are not configured as Brian suggested, Civil 3d will be prompting the user for description and elevations for each single point that will be converted
On the other hand, there are programs such as STWAVE (for waves modeling) where the user has to define the seabed surface with points as an input for the calculation of waves heights.
April 14, 2011 at 9:04 am
Vicky,
The settings can also be set by expanding the point creation tools.
January 5, 2012 at 2:16 pm
Thanks for the information, it was very helpful in extracting the points to do my modeling
January 30, 2012 at 6:27 am
Thanks for this helpful tip :)
January 30, 2012 at 1:16 pm
I’m glad it helped you out.
February 27, 2012 at 12:26 pm
Hi.I need to extract points from a surface, but at some specific locations. The surface was created from survey data. Actually, it is more like I would like to specify a grid (set of x,y coordentates) and obtaing the surface elevation at each location. With that data, I plan to use a parametrical model of the desired land surface, and to run an algorithm that finds parameters that optimize some earth moving criteria. Surface data at an appropriate sampling grid, facilitates the comparison between actual land surface and the modeled desired surface. Is such surface extraction possible from Civil 3D? Thanks.
February 29, 2012 at 8:25 am
In this case, I wouldn’t use the surface points but I would use standard Cogo Points instead. There is an option to create points on a grid that will get the elevation from the surface. You can then simply export those cogo points out to a file.