Rhino 3D Scripting Skill

Write production-quality scripts for Rhinoceros 3D. Covers the three scripting surfaces (RhinoScript/VBScript, RhinoPython, direct RhinoCommon .NET) and the Rhino 8+ Script Editor.

When to Use This Skill

• User asks to write, edit, or debug a .rvb, .vbs, or .py Rhino script
• User wants a Rhino command macro or wants to automate a sequence of Rhino commands
• User wants to manipulate geometry, layers, blocks, materials, viewports, or annotations from code
• User mentions rhinoscriptsyntax, scriptcontext, RhinoCommon, Rhino.Geometry, RhinoDoc, or the Script Editor
• User wants to pick objects, prompt for input, or build a small UI inside Rhino
• User asks how to load, run, or distribute a script (startup scripts, aliases, toolbar buttons)

Choosing a Scripting Surface

Pick the surface based on the task, not preference. Recommend Python by default for new work.

A macro is not a script — it is a string of command-line input (e.g. ! _-Line 0,0,0 10,0,0 _Enter). Use a script the moment you need a variable, loop, or conditional.

Prerequisites

• Rhino 7 or later (Rhino 8 strongly recommended — unified Script Editor supports Python 3, VB, and C# in one window).
• Script Editor: type _ScriptEditor (Rhino 8) or _EditPythonScript / _EditScript (older).
• Run a saved file from the command line with _-RunPythonScript or _LoadScript + _RunScript.

Core Patterns

Python: minimal scaffold

import rhinoscriptsyntax as rs
import scriptcontext as sc
import Rhino

def main():
    obj_id = rs.GetObject("Select a curve", filter=rs.filter.curve, preselect=True)
    if not obj_id:
        return
    length = rs.CurveLength(obj_id)
    print("Length: {0:.4f}".format(length))

if __name__ == "__main__":
    main()

Python: working with RhinoCommon directly

import Rhino
import scriptcontext as sc

doc = sc.doc  # Rhino.RhinoDoc.ActiveDoc
tol = doc.ModelAbsoluteTolerance

circle = Rhino.Geometry.Circle(Rhino.Geometry.Point3d(0, 0, 0), 5.0)
curve_id = doc.Objects.AddCircle(circle)
doc.Views.Redraw()

VBScript: minimal scaffold

Option Explicit

Call Main()

Sub Main()
    Dim strObject
    strObject = Rhino.GetObject("Select a curve", 4)  ' 4 = curve filter
    If IsNull(strObject) Then Exit Sub
    Rhino.Print "Length: " & Rhino.CurveLength(strObject)
End Sub

Picking objects with a custom filter (Python, RhinoCommon)

import Rhino
import scriptcontext as sc

go = Rhino.Input.Custom.GetObject()
go.SetCommandPrompt("Select breps")
go.GeometryFilter = Rhino.DocObjects.ObjectType.Brep
go.SubObjectSelect = False
go.GetMultiple(1, 0)
if go.CommandResult() != Rhino.Commands.Result.Success:
    pass
else:
    ids = [go.Object(i).ObjectId for i in range(go.ObjectCount)]

Step-by-Step Workflows

Bulk-modify many objects fast

1. Disable redraw: rs.EnableRedraw(False).
2. Wrap mutations in a single undo record: undo = doc.BeginUndoRecord("My Op") … doc.EndUndoRecord(undo).
3. Use RhinoCommon directly inside the loop (skip rhinoscriptsyntax overhead).
4. Re-enable redraw and call doc.Views.Redraw() in a try/finally so a crash never leaves the viewport frozen.

Distribute a script to a teammate

1. Save the .py / .rvb somewhere on disk.
2. Add the folder to Options → Files → Search paths so Rhino can find it by name.
3. Create a toolbar button or alias whose macro is:
   • Python: ! _-RunPythonScript "MyScript.py"
   • RhinoScript: ! _-LoadScript "MyScript.rvb" _-RunScript MySubName
4. The leading ! cancels any running command; - runs the command in script (no-dialog) mode.

Run code at Rhino startup

1. Place a .rvb/.py in a search path.
2. Tools → Options → RhinoScript (or Python) → add to Startup list. The file executes once per session.

Gotchas

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