Applicable to SunDAT Pro & Standard


How do I create a topo surface from DWG into Sketchup/SunDAT?


  • Topo surfaces can only be created from 2D polylines.  Topo surfaces cannot be created from 3D Polylines, COGO points, AutoCAD Points, blocks.
  • Reduce the complexity of the DWG by cleaning up the file so it only has the contour lines and boundary.


  1. In the SketchUp, go to File->Import
  2. In the Import window, select AutoCAD Files (*.dwg, *.dxf) as import.  Then select the DWG file to import but do not click Import yet.
  3. Click the Options... button.  Check the Scale is set to the unit that matches with the DWG file drawing units.  Click OK, then Import
  4. A message box will appear asking do you want to explode the import and attempt to create faces.  Make sure to click No.  The linework will be brought into SketchUp as a single group.
  5. In SunDAT, go to the Topography panel.  Select the CAD tab.
  6. In the Select Boundary Layers, select the name of the layer of the edge of the project boundary (this will be the edge of the PV region).  If you do not know the layer, you can find it by double clicking the group to get into Group Editing mode.  Then select the edge of the project boundary.  In the default tray, expand Entity Info and you will be able to see the layer which you will use for the Boundary layer input.  If you are planning to have more than one region, and the boundary of each region is on a different layer, you can select more than one layer.
  7. In the Select Contour Layers, select the name of the contour layer.  If you don't know the layer, follow the same instructions as the previous step.  You can select more than one layer if for example you have major and minor contour lines.
  8. Press the Convert button to begin creating the topo surface.  Please note this can be a time consuming process depending on the size and complexity of the terrain.  At the bottom of the screen you can see the progress of the topo surface creation.
  9. When it is finished, the topo surface will be created in your model ready for use.  Also face(s) will be created which can be used for your PV region.