Home » Tech Tip: AutoCAD Map 3D – Coordinate Systems

Tech Tip: AutoCAD Map 3D – Coordinate Systems

Tech Tip AutoCAD Map 3D: Coordinate Transformation

Map Tools – Coordinate Transformation

The AutoCAD Geographic Information System (GIS) and Mapping toolset is model-based GIS mapping software that provides access to CAD and GIS data to support planning, design and management.

Use the Map tools to move CAD objects between the different Coordinate Systems in the Civil 3D Library.

Assigning Coordinates

Use the MAPCSASSIGN command or change the Workspace to Planning and Analysis and in the Map Setup tab, click the Assign button.  All of the available Coordinate Systems are displayed in the Coordinate System form so use the Search field for “MGA” (Map Grid Australia) for example.  Choose the source Coordinate System for your data and note the Datum in the Referenced To column.

Note that once the Coordinate System has been set, the Geolocation tab is available where users can activate an Aerial Map.

Create a new drawing and Assign the new Coordinate System.  If you are using the MGA map grids with the GDA 2020 Datum, there are 3 options denoted as 7P, C and CD.  These are the transformation methods used to reference the new Datum and stand for Seven Parameter, Conformal, and Conformal with Distortion respectively.  More information can be found on the different methods here. You can also find more information on which version of the 2020 Datum to use here.

Assign Coordinate System
Screenshot of assigning a Coordinate System.
Screenshots of Track Coordinates
Screenshot of track Coordinates

Create a Map Query

In the View tab, click to open the Map Task Pane or use the MAPWSPACE command.  Click on the Map Explorer tab and attach your source data by dragging and dropping it into the Panel.  Note that source data must be closed to be available for Attachment so Save and Close your Drawing first.  Right click on Query Library and Define… to open the Define Query form.  Apply data filters or specify Location… > All for all of the data.  This reveals the Query Mode; choose Draw and Execute Query to draw the CAD data in the new drawing to the new Coordinate System.  Civil 3D elements such as COGO Points, Alignments, Surfaces and Corridors are not included in the Map Transformation.

Tracking the Coordinates

Click the Customization button and display the Coordinates. This will show a real time track of your cursor position in the X,Y and Z axis. Go to the Analyze tab and click the Track Coordinates button or use the MAPTRACKCS command. This panel can display the cursor position in multiple Coordinate Systems at the same time.

Want to learn more?

Check out our video ‘AutoCAD Map 3D: Coordinate Systems‘.