Monday, December 16, 2013

 
 

How to scale Civil 3D Points without scaling Elevations

As you might be aware, when you use the AutoCAD Scale command to scale Civil 3D Points, the elevations of the points are scaled along with the x and y coordinates.
We have a few different methods of working around this limitation.
 
1. Delta Engineering Systems has written a VisualLISP routine that will scale the points while maintaining the elevations. You select the points on the screen, give a basepoint and scale factor, and the routine does the rest. If you are interested in obtaining this routine, free of charge, please contact Tim Corey at Delta Engineering Systems, tcorey@Shasta.com or 530.221.2994.
 
2. Use the Survey database (Survey tab of the Ribbon) to import the points from an Autodesk Fieldbook file (*.fbk). Most data recorders include software that will convert their files to Autodesk .fbk format. Once you have that file, add the line: SCALE FACTOR <>, for example: SCALE FACTOR 1.00043, to the .fbk file before any new points are listed. Import the fbk using Import Events in the Survey Database.
 
3. Use Civil 3D's Drawing Settings, Transformation tab to apply a scale factor to existing points. The Grid Easting and Grid Northing columns of the Point List will now have the scaled coordinates. Create a Point File Format the includes the Grid Easting and Grid Northing along with Point Number, Elevation, and Description. Export to this format. Erase the points. Now import the previously exported file using a Point File Format that uses Northing and Easting instead of Grid Northing and Easting. The new points will have the same points numbers and elevations as before, but the coordinates will have changed to the scaled values.
 
4. Chris at Civil3dReminders.com has written a VB.NET program you can copy here:
 
We have not tested Chris's solution, but wanted to be sure you know about it as a possible solution.
 
Happy scaling!