QGIS → Rhino / Grasshopper

A Grasshopper definition that rebuilds QGIS site data as Rhino geometry.

The problem

Getting real site context — building footprints, roads, parcels, terrain — out of QGIS and into Rhino is a notorious pain: projection mismatches, lat/long in degrees, geometry that lands kilometres from the origin, and no clean importer.

What this does

A downloadable GHPython script + Grasshopper definition that reads a GeoJSON exported from QGIS, handles the projection/origin offset, and rebuilds it as Rhino curves and attribute-extruded building masses — so your site model is ready in minutes, not an afternoon of cleanup.

Downloads

geojson_to_rhino.py (GHPython)Paste into a GHPython component (Rhino 7 / 8). Stdlib only — no install.

What it does

You export your QGIS layer as GeoJSON (in a projected, metre-based CRS). The Grasshopper definition reads the file, parses each feature's geometry, recentres it near the Rhino origin, and builds:

Polylines for roads, parcel boundaries, and contours (LineString / Polygon rings)
Extruded building masses driven by a height attribute (e.g. height or levels)
Points for trees, sensors, or labelled locations

Why it's useful

Skips the projection / "geometry is 2 km from origin" nightmare.
Attribute-driven extrusion — building heights come straight from the data.
Plain GHPython using the standard library, so it's easy to read and modify.

How to use

In QGIS, reproject your layer to a local metric CRS (e.g. SVY21 / UTM) and export as GeoJSON.
Drop the .gh definition into Grasshopper and point the file path at your GeoJSON.
Set the height attribute name and the origin offset; bake the result into Rhino.

Honest limits

Very large datasets should be clipped to your site in QGIS first.
Curved geometries are exported as dense polylines (GeoJSON has no arcs).