A frequent question is how to import Lidar data like LAS/LAZ or other point cloud formats into Civil3D.  Here is a step by step procedure on the process, using Civil3D 2018 as the target.  The procedure assumes you  have your Lidar data files downloaded and ready in a folder.

First Step: Prepare the Lidar Data

Because recent versions of Civil3D don’t allow you to filter by classification, you need to break your source data into separate files first.  This actually is a good idea because the remaining steps will have less data to process and will move faster.

The key to this step is a tool called LasSplit from Martin Isenburg at rapidlasso.   You can use LasSplit to break massive files into multiples by interval but most importantly by classification.  Separating your Class 2 (ground points) is critical.  Detailed instructions are on the LasSplit page so we won’t reproduce them here.

Second Step: Prepare the Recap Project

  1. Launch Autodesk Recap, a separate product installed with Civil3D.  You will find this in the Start menu, or in the Point Cloud panel of the ribbons Insert tab.
  2. Click the large [Scan Project] button.
  3. Click the folder field at the bottom of the “Create New Project” dialog and navigate to the folder containing your (split?) source lidar files.
  4. Click the project name field at the top of the same dialog and optionally change the name.
  5. Click the [Proceed] button in the lower right.
  6. Click the [+ Select Files to Import] button.
  7. Select all the LAS/LAZ files applicable to the project, click OK.
  8. Click the [Import Files] button in the lower right.
  9. Wait while Recap imports the files into the project (thick rings are yet to be done, thin ones are finished).
  10. Click the [Index Scans] button in the lower right.
  11. If necessary wait for all files to be indexed.  Completed files should have a cog with a check mark in the upper right corner.
  12. Click the [Launch Project] button in the lower right.
  13. Click the [Home] icon in the upper left, click the Save button.

Third Step: Preparing the Point Cloud

If you haven’t already, launch Civil3D and load an existing drawing or create a new one.  You may need to assign a coordinate system using the ToolSpace Settings tab, right click the drawing name, choose Edit Drawing Settings.

  1. Activate the Insert tab of the ribbon, choose Attach in the Point Cloud panel.
  2. Navigate to the data folder used in the above procedure and select the .RCP file created.
  3. Review the details if desired, noting the number of points and height  Note the height to help determine an appropriate contour interval in the next step.
  4. Zoom extents if necessary to see the point cloud in your drawing.

Fourth Step: Creating the Surface

  1. Activate the Home tab of the ribbon, click Surfaces in the “Create Ground Data” panel, then choose “Create Surface from Point Cloud”.
  2. You will be prompted to select the point cloud, you can’t pick in the middle.  Although it’s may not be visible pick an edge like left, or top.
  3. Optionally change the name, enter a description and choose a display style.
  4. Click the [Next] button to review the total points in the cloud.
  5. Click the [Create Surface] button to begin.

The application tells you that you can continue to work while the surface is being created.  Large data sets may require some time.  Sadly the ability to limit the surface to lidar classifications is missing!  Hopefully this will be restored in a service pack.

Single Step Alternative:  If you value your time there is a single step alternative in our C3D Surfaces module.  It’s Mass Points Processor lets you select multiple source data files (LAS, LAZ and more), specify your desired classifications, elevation range, area of interest (any closed object) and more.  In a short unattended period you will have a TinSurface ready to move forward.

Important: Keep your source files!  Applications come and go with their proprietary formats and there may come a time you need to rebuild your project in another application.  When that time comes you can’t count on current software to be available or even guaranteed compatible.  As an example anyone who stored their data exclusively using Ambercore ISD files found that data orphaned!

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