Export to 3DM

Export Revit geometry to Rhino 3DM format with WYSIWYG coordinate accuracy. Preserves spatial relationships across round-trip workflows.

What It Does

Export to 3DM converts your Revit geometry into Rhino 3DM format files with WYSIWYG (What You See Is What You Get) coordinate preservation. The command maintains sub-millimeter coordinate accuracy so geometry lands exactly where it should when you open it in Rhino.

Key features:

  • WYSIWYG Coordinates — Exported geometry preserves spatial relationships regardless of coordinate system
  • File-Level Metadata — Complete coordinate context stored in the 3DM file for reliable round-trip workflows
  • Broken Geometry Recovery — Recovers partial geometry from invalid solids through face extraction

Perfect for:

  • Round-trip workflows (Rhino → Revit → Rhino)
  • Complex geometry that needs further refinement in Rhino
  • Collaboration between Revit and Rhino users
  • Preserving coordinate systems across platforms

Export Dashboard

The Export Dashboard provides a modern interface for configuring and executing exports.

Section Purpose
Element Selection Shows selected elements and geometry count
Coordinate System Choose Internal Origin, Project Base Point, or Survey Point
Output Settings Set file name and destination folder
Progress Real-time export progress with element-by-element status

The dashboard uses responsive layout with minimum 800×600 dimensions and consistent Senibina branding.

How to Use

  • Open your Revit project
  • Select the elements you want to export
  • Click Export to 3DM in the Revit Project to Rhino panel
  • In the Export Dashboard:
    • Verify selected elements
    • Choose your Coordinate System (Internal Origin, Project Base Point, or Survey Point)
    • Set the output file name and location
  • Click Export and wait for completion
  • Open the 3DM file in Rhino

The geometry appears in Rhino at the exact same coordinates as in Revit, relative to the selected coordinate system.

Coordinate Systems

System Use Case
Internal Origin Default Revit origin — best for isolated geometry
Project Base Point User-defined project origin — best for coordinated projects
Survey Point Real-world coordinates — best for site-level coordination

WYSIWYG Behavior: All elements use the same coordinate system during export, regardless of how they were originally imported. This ensures consistent spatial relationships in the exported 3DM file.

What Gets Exported

Supported geometry types:

  • FreeForm elements (from Senibina-Bridge's [Import Solids] workflows)
  • Family instances with solid geometry
  • Generic models
  • Modified families (with joins, cuts, or openings)

What's preserved:

  • Coordinate positions (sub-millimeter accuracy)
  • Solid geometry shapes
  • Spatial relationships between elements
  • File-level coordinate metadata for round-trip workflows

Not exported:

  • Revit-specific data (views, sheets, schedules)
  • 2D elements (detail lines, text, dimensions)
  • Annotation elements
  • System families (walls, floors, roofs)

Round-Trip Workflows

Export to 3DM uses Schema v2.0 file-level metadata to maintain coordinate accuracy across round-trip workflows:

  • Import from Rhino (using [Import Solids] commands)
  • Work in Revit (modify, place, coordinate)
  • Export back to Rhino (using Export to 3DM)
  • Result: Geometry returns to original coordinates in Rhino

How it works:

  • File-level metadata stores complete coordinate context in the 3DM document
  • Aggregate bounding box calculated from native elements only (stable reference frame)
  • Exported geometry center stored for WYSIWYG offset calculation during import
  • Each import operation is self-contained, relying only on file-level metadata

Troubleshooting

Export button is greyed out

What to do:

  • Make sure you have elements selected in Revit
  • Verify Rhino 8 is installed
  • Check that you're working in a Revit project (not family editor)

Geometry appears at wrong location in Rhino

Possible causes:

  • Different coordinate system selected during import vs export
  • Project Base Point moved after import
  • Survey Point changes between operations

What to do:

  • Use the same coordinate system for import and export
  • Verify Project Base Point hasn't moved
  • Re-import the original geometry to refresh metadata
  • Check position validation logs if available

Some elements don't export

Common reasons:

  • Elements have no solid geometry
  • System families not supported (walls, floors, roofs)
  • Elements are 2D only (detail lines, text)
  • Invalid or broken geometry

What to do:

  • Check that elements contain solid geometry
  • Use supported element types (see "What Gets Exported" section)
  • Try exporting elements individually to identify problem elements
  • For broken geometry, the command recovers what it can through face extraction

Export takes a long time

Normal: Processing 500+ elements may take a few minutes

What to do:

  • Export smaller batches if needed
  • Let the progress indicator complete (don't cancel)
  • Close unnecessary applications to free memory
  • The dashboard shows element-by-element progress

Broken geometry exports incompletely

What happens: Some surfaces export but solid is incomplete

Why: The command uses face extraction fallback to recover what it can from invalid geometry

What to do:

  • This is expected behavior for broken geometry
  • Re-import from clean Rhino geometry if possible
  • Simplify the original geometry to avoid breaks
  • Use the recovered surfaces as-is (better than nothing)

Tips

Tip Details
Batch exports Select multiple elements to export them all at once
Coordinate consistency Use the same coordinate system for import and export
File naming Name exported 3DM files clearly (include date or version)
Quality check Open 3DM file in Rhino immediately to verify export success
Memory management Close export dashboard after completion to free resources