Calculate Curve Intersections

Demonstrates how to calculate the intersection points between two user-specified curves.

partial class Examples
{
public static Rhino.Commands.Result IntersectCurves(Rhino.RhinoDoc doc)
{
// Select two curves to intersect
var go = new Rhino.Input.Custom.GetObject();
go.SetCommandPrompt("Select two curves");
go.GeometryFilter = Rhino.DocObjects.ObjectType.Curve;
go.GetMultiple(2, 2);
if (go.CommandResult() != Rhino.Commands.Result.Success)
return go.CommandResult();

// Validate input
var curveA = go.Object(0).Curve();
var curveB = go.Object(1).Curve();
if (curveA == null || curveB == null)
return Rhino.Commands.Result.Failure;

// Calculate the intersection
const double intersection_tolerance = 0.001;
const double overlap_tolerance = 0.0;
var events = Rhino.Geometry.Intersect.Intersection.CurveCurve(curveA, curveB, intersection_tolerance, overlap_tolerance);

// Process the results
if (events != null)
{
for (int i = 0; i < events.Count; i++)
{
var ccx_event = events[i];
if (ccx_event.PointA.DistanceTo(ccx_event.PointB) > double.Epsilon)
{
}
}
doc.Views.Redraw();
}
return Rhino.Commands.Result.Success;
}
}

Partial Friend Class Examples
Public Shared Function IntersectCurves(ByVal doc As Rhino.RhinoDoc) As Rhino.Commands.Result
' Select two curves to intersect
Dim go = New Rhino.Input.Custom.GetObject()
go.SetCommandPrompt("Select two curves")
go.GeometryFilter = Rhino.DocObjects.ObjectType.Curve
go.GetMultiple(2, 2)
If go.CommandResult() <> Rhino.Commands.Result.Success Then
Return go.CommandResult()
End If

' Validate input
Dim curveA = go.Object(0).Curve()
Dim curveB = go.Object(1).Curve()
If curveA Is Nothing OrElse curveB Is Nothing Then
Return Rhino.Commands.Result.Failure
End If

' Calculate the intersection
Const intersection_tolerance As Double = 0.001
Const overlap_tolerance As Double = 0.0
Dim events = Rhino.Geometry.Intersect.Intersection.CurveCurve(curveA, curveB, intersection_tolerance, overlap_tolerance)

' Process the results
If events IsNot Nothing Then
For i As Integer = 0 To events.Count - 1
Dim ccx_event = events(i)
If ccx_event.PointA.DistanceTo(ccx_event.PointB) > Double.Epsilon Then
End If
Next i
doc.Views.Redraw()
End If
Return Rhino.Commands.Result.Success
End Function
End Class

import Rhino
import scriptcontext

def IntersectCurves():
# Select two curves to intersect
go = Rhino.Input.Custom.GetObject()
go.SetCommandPrompt("Select two curves")
go.GeometryFilter = Rhino.DocObjects.ObjectType.Curve
go.GetMultiple(2, 2)
if go.CommandResult()!=Rhino.Commands.Result.Success: return

# Validate input
curveA = go.Object(0).Curve()
curveB = go.Object(1).Curve()
if not curveA or not curveB: return

# Calculate the intersection
intersection_tolerance = 0.001
overlap_tolerance = 0.0
events = Rhino.Geometry.Intersect.Intersection.CurveCurve(curveA, curveB, intersection_tolerance, overlap_tolerance)

# Process the results
if not events: return
for ccx_event in events: