Tractrix for Revit manual
Tractrix for Revit brings the same commands as the AutoCAD add-in into Revit. Results are drawn as view-specific elements in the active plan or drafting view, so they never enter your model geometry or schedules.
Dialogs may change before 1.0. The commands, engine and results are shared with Tractrix for AutoCAD; this manual covers what is specific to Revit.
On this page
Installation
- Revit 2025 or later on 64-bit Windows 10 or 11. The add-in targets .NET 8.
- Local engine bundled with the add-in, or a Tractrix Cloud API token.
- Close Revit and run the installer from the download centre. It installs the add-in manifest for your Windows user.
- Start Revit. When Revit asks about the unsigned or new add-in, choose Always load.
- Open a floor plan or site plan view: the commands draw into the active plan view.
- On the Tractrix ribbon tab, open Settings (TXSETTINGS) and choose the engine.
Engine
The engine options are the same as in AutoCAD: the local engine runs tractrix-engine on your computer, found through the settings path, the TRACTRIX_ENGINE environment variable, %ProgramData%\Tractrix\engine, the add-in's engine folder or PATH; the cloud engine sends requests to Tractrix Cloud with an API token stored encrypted for your Windows user in %AppData%\Tractrix\settings.json. See engine set-up.
Commands
The ribbon buttons run the same operations as the AutoCAD commands:
| Command | Select in the view | Result |
|---|---|---|
| TXPATH | Model or detail lines forming the path; optional pavement and obstacle outlines | Envelopes, tracks, footprints, issues |
| TXPUSHBACK | The pushback or tow path | Aircraft and tug envelopes, tracks, issues |
| TXTURN | Optional point and heading for the 180° turn | Radii table and 180° turn |
| TXJETBLAST | Positions and headings | Jet blast contours and intake hazard areas |
| TXGSE | The vehicle path | Vehicle and trailer envelopes, issues |
| TXLIBRARY | — | Aircraft and vehicle libraries |
| TXSETTINGS | — | Engine and drawing options |
| TXCLEAR | — | Removes Tractrix elements from the view |
| TXREPORT | — | HTML or CSV report of the runs |
| TXRERUN | A Tractrix result | Runs its stored request again |
Command options are described in the AutoCAD manual. Stand design and taxiway fillets will follow with protocol v1.1.
Line styles and filled regions
Revit has no layers, so each TX layer maps to a Revit line style (a subcategory of Lines) and, for areas, a filled-region type. Their names follow the AutoCAD layer names in title case: TX-ENVELOPE becomes the line style TX-Envelope, TX-TRACK-NOSEGEAR becomes TX-Track-Nosegear. Jet blast contours use filled-region types such as Tractrix – Jet blast 56 km/h.
- Areas (envelopes, swaths, issues, contours) are filled regions, outlined in the matching line style.
- Tracks and footprints are detail lines.
- Where Revit cannot show fill transparency, the fill colour is pre-blended with white to the same visual weight.
- Control visibility with Visibility/Graphics → Annotation Categories / Lines or a view template.
Units
Revit stores lengths internally in decimal feet. The add-in converts to metres (1 ft = 0.3048 m, exact) before sending a request and back when drawing, whatever display units the project uses. Coordinates are those of the view's internal origin; headings are degrees clockwise from the project's +Y axis.
Troubleshooting
- Nothing is drawn: make sure a plan or drafting view is active, not a 3D view, section or schedule.
- Engine not found
- Cloud token rejected
- Steering exceedance explained