A government agency IT person called the other day and asked if we could sell him the Civil 3D Coordinate System Transformation Tool. One of his Civil 3D users pointed him to this site of the Framework for Civil 3D for some reason. Maybe the user watched a video?
Good news. I was happy to explain that the coordinate system transformation capabilities were included for free in Autodesk Map 3D which is part of Autodesk Civil 3D. He hung up before I could explain that there is some nuance and there is a separate tool. Oh. Bother.
Map Coordinate System Transformation
The Map ATTACH and QUERY tools do allow us to transform any AutoCAD primitives from a drawing in one supported Autodesk coordinate system to another.
Maybe you remember? Back in the day we could once Map Query Civil 3D objects too. Sadly, Autodesk removed those capabilities from Civil 3D a long time ago. Converting and transforming a finished Civil 3D project drawing got a bit more complicated. You know the drill.
We can dumb down (publish) our Civil 3D drawings to the AutoCAD primitive level and then transform the results and produce almost acceptable published results. At least the picture of our Civil 3D drawing ends up in the right place. I hope that makes sense.
Yes. This an art that takes considerable practice to work all the kinks out of the workflow. If you have to do this type of conversion in Civil 3D, it is truly painful and time consuming.
Autodesk Coordinates Transformation for Civil 3D
After many years of Civil 3D user whines Autodesk released the first Autodesk Coordinates Transformation for Civil 3D tools as an Extension to Civil 3D 2022. There is an existing Civil 3D 2023 version of this extension.
See Autodesk Coordinates Transformation for Civil 3D 2023 in help. You can change the release number in the link to get to the Civil 3D 2022 version of the extension.
Hopefully, we will see an Autodesk Civil 3D 2024 version real soon now.
The Coordinate Transformation Tool provides vital tools for civil engineering projects where we may need to transform Autodesk Civil 3D Feature (objects) from one coordinate system to another within the drawing environment.
The Coordinate Transformation Tool allows for horizontal transform, vertical datum transform, and a special case vertical units transform from US Survey Foot to International Foot and from International Foot to US Survey Foot.
To confuse matters, the Coordinates Transformation tool appears in the Civil 3D Toolbox >> Miscellaneous tab interface as the Drawing Conversion Tool. Say What?
Drawing Transformation Tools
The Toolbox name makes some sense when we understand that the Drawing Conversion Tool works in the single drawing context.
The Tool only functions in a drawing with an assigned coordinate system. It changes the drawing and the contents.
Inside the tool:
- The Coordinate System Transformation dialog box allows us to assign a target category and specific coordinate system.
- The mission critical Options button controls the transformation details via the specifics set up in the Transformation Options dialog box.
The Drawing Transformation Tool produces a comprehensive report of what was transformed (and what was not) along with the before and after coordinates to help us validate the accuracy of the transformed results.
The Drawing Transformation Tool for Civil 3D 2023
Needless to say, we want to employ the Drawing Transformation Tools on a copy of a Civil 3D project drawing. This will usually be a publish drawing with Reference Templates removed.
The Drawing Transformation Tool:
- Does not support transformation between metric and Imperial units
- Does not support XREFs.
Transform the XREFs separately - Does not currently support DREFs for obvious reasons.
Promote the project DREF Civil 3D Features first or convert the source drawings separately. - Does not convert Survey Points but can convert Survey point to COGO points if set in the Options
- Alignments are transformed by moving pass-through points (such as start of alignment or fixed tangents).
The dimensions in the alignment (arc radius, A value, or spiral length) with not be adjusted.
This maintains the design intent of the alignment during transformation. - DEMs (non-TIN surfaces), rasters, and images with insert points transform at the insertion point.
They will not rotate or adjust due to the transformation
For complex Civil 3D project drawings and Complex or Multiple Baseline Corridor models, we may want to divide and conquer the project data beforehand to better QAQC the initial Drawing Transformation Tool results.
In other words, we may want to convert and transform the DREF data sources separately and put a final published result back together again in a transformed version of the project.
I do like to remind folks that Civil 3D’s Survey database capabilities include built-in transformation capabilities for Survey data types. It always pays to employ the deep Civil 3D Survey features and benefits wisely in our projects. We plan to succeed.
The Transformation for Civil 3D
Get the Framework for Civil 3D Release 8