Import Reference Lines (RFA)

Import Rhino curves as Reference Lines for family construction geometry. Configure curve settings and select layers from a single dashboard.

What It Does

Import Reference Lines converts Rhino curves into Revit Reference Lines—construction geometry that helps you build parametric families. Reference Lines guide family elements but don't appear in projects when the family is loaded.

Everything happens through a single Import Dashboard where you select your file, pick layers, configure curve settings, and run the import with real-time progress tracking.

When to Use This

Use Import Reference Lines when:

  • Building parametric families that need construction geometry
  • Creating reference geometry to drive family element placement
  • Setting up dimensions and constraints in families
  • Importing curves that shouldn't be visible in projects

For visible curves, use Import Model Lines instead.

How to Use

Step 1: Open a Family Document

  • Open an existing family or create one from a template
  • Reference Lines only work in family documents

Step 2: Open the Import Dashboard

  • Click Import Reference Lines (RFA) in the Rhino to Revit Family panel
  • The Import Dashboard opens

Step 3: Select Your File

  • Click Browse to select your .3dm file
  • Your last used file is remembered for next time

Step 4: Select Layers

  • Available layers load automatically from your file
  • Each layer shows its Rhino color for easy identification
  • Select the layers containing curves you want to import

Step 5: Configure Curve Settings

Expand the Curve Settings section to adjust:

Points per Curve (slider: 2-50, default: 10)

  • Controls point sampling for complex curves converted to splines
  • Lower values = faster, simpler geometry
  • Higher values = more accurate curves

Force Convert to Splines (toggle)

  • Off (recommended): Preserves native curve types (smaller file, better performance)
  • On: Converts everything to splines (use only if native curves cause issues) or if NURBS Curves are required.

Step 6: Run Import

  • Click Start Import
  • Watch real-time progress as curves convert to Reference Lines
  • Review the completion summary with curve type breakdown

Curve Conversion

The command intelligently recognizes curve types:

Rhino Curve Revit Result Notes
Lines Native lines Best performance
Arcs Native arcs Properties preserved
Circles Two semicircular arcs Standard Revit behavior
Ellipses Native ellipses Full accuracy
Polylines Individual line segments Vertices preserved
Complex curves Splines Uses Points per Curve setting

Native curve types result in 82% smaller file sizes compared to splines.

What You Get

In your family document:

  • Reference Lines for construction geometry
  • Native curve types where possible
  • Curves ready for dimensions and constraints

Troubleshooting

Dashboard doesn't open

Try these steps:

  • Ensure you're in a Revit family document (.rfa), not a project
  • Click the button again
  • Restart Revit if the issue persists

Some curves missing after import

Possible causes:

  • Curves may be too short or too long
  • Curves are invalid in Rhino
  • Curves are on layers you didn't select

Circles appear as two arcs

This is expected. Revit represents circles as two semicircular arcs. They function correctly for dimensions and constraints.

Reference Lines not visible

What to check:

  • Reference Lines are construction geometry
  • They're visible in family editor views but not when loaded in projects
  • Check your view visibility settings

Tips

  • Native curves are faster: Leave "Force convert to splines" off for best performance
  • Start with default points: Use 10 points per curve, increase only if curves look too simple
  • Layer organization: Use Rhino layers to organize curves before import
  • Settings persist: Your preferences are saved between sessions