c3d-project-setup
Installation
SKILL.md
Civil 3D .NET Project Setup
Use this skill when creating a new Civil 3D plugin project or troubleshooting build/reference issues.
Project Type
- Class Library targeting .NET 8.0 (or .NET Framework 4.8 for older C3D versions)
- Platform: x64 only
- Output: DLL loaded via
NETLOADcommand in Civil 3D
Required DLL References
The acad_path.props file defines three path variables for the three subdirectory locations where Civil 3D DLLs reside:
| Variable | Resolved Path | DLLs |
|---|---|---|
$(ArxMgdPath) |
C:\Program Files\Autodesk\AutoCAD 2026 |
acdbmgd.dll, acmgd.dll, accoremgd.dll |
$(OMFMgdPath) |
C:\Program Files\Autodesk\AutoCAD 2026\ACA |
AecBaseMgd.dll |
$(AeccMgdPath) |
C:\Program Files\Autodesk\AutoCAD 2026\C3D |
AeccDbMgd.dll |