Circle

Public Struct

Represents a circle in 3D.

The values used are a radius and an orthonormal frame of the plane containing the circle, with origin at the center.

The circle is parameterized by radians from 0 to 2 Pi given by

t -> center + cos(t)*radius*xaxis + sin(t)*radius*yaxis

where center, xaxis and yaxis define the orthonormal frame of the circle plane.

Namespace: Rhino.Geometry

Assembly: RhinoCommon (in RhinoCommon.dll)

Syntax

[SerializableAttribute]
public struct Circle : IEpsilonComparable<Circle>,
  ICloneable

The Circle type exposes the following members.

Constructors

Name

Description

---

Public Method

Circle(Arc)

Initializes a circle from an arc.

---

Public Method

Circle(Double)

Initializes a circle with center (0,0,0) in the world XY plane.

---

Public Method
Code Example

Circle(Plane, Double)

Initializes a circle on a plane with a given radius.

---

Public Method
Code Example

Circle(Point3d, Double)

Initializes a circle parallel to the world XY plane with given center and radius.

---

Public Method

Circle(Plane, Point3d, Double)

Initializes a circle parallel to a given plane with given center and radius.

---

Public Method

Circle(Point3d, Point3d, Point3d)

Initializes a circle through three 3d points.

---

Public Method
Circle(Point3d, Vector3d, Point3d)

Initializes a circle from two 3d points and a tangent at the first point. The start/end of the circle is at point “startPoint”.

---

Properties

Name

Description

---

Public Property

BoundingBox

Gets the circle’s 3d axis aligned bounding box.

---

Public Property

Center

Gets or sets the center point of this circle.

---

Public Property

Circumference

Gets or sets the circumference of this circle.

---

Public Property

Diameter

Gets or sets the diameter (radius * 2.0) of this circle. Diameters should be positive values.

---

Public Property

IsValid

A valid circle has radius larger than 0.0 and a base plane which is must also be valid.

---

Public Property

Normal

Gets the normal vector for this circle.

---

Public Property

Plane

Gets or sets the plane of the circle.

---

Public Property

Radius

Gets or sets the radius of this circle. Radii should be positive values.

---

Public Property
Static Member

Unset

Gets a circle with Unset components.

---

Methods

Name

Description

---

Public Method

ClosestParameter

Gets the parameter on the circle which is closest to a test point.

---

Public Method

ClosestPoint

Gets the point on the circle which is closest to a test point.

---

Public Method

DerivativeAt

Determines the value of the Nth derivative at a parameter.

---

Public Method

EpsilonEquals

Check that all values in other are within epsilon of the values in this

---

Public Method

Equals

Indicates whether this instance and a specified object are equal.

(Inherited from ValueType.)

---

Public Method

GetHashCode

Returns the hash code for this instance.

(Inherited from ValueType.)

---

Public Method

GetType

Gets the Type of the current instance.

(Inherited from Object.)

---

Public Method

IsInPlane

Evaluates whether or not this circle is co-planar with a given plane.

---

Public Method

PointAt

Circles use trigonometric parameterization: t -> center + cos(t)*radius*xaxis + sin(t)*radius*yaxis.

---

Public Method

Reverse

Reverse the orientation of the circle. Changes the domain from [a,b] to [-b,-a].

---

Public Method

Rotate(Double, Vector3d)

Rotates the circle through a given angle.

---

Public Method

Rotate(Double, Vector3d, Point3d)

Rotates the circle through a given angle.

---

Public Method

Rotate(Double, Double, Vector3d)

Rotates the circle around an axis that starts at the base plane origin.

---

Public Method

Rotate(Double, Double, Vector3d, Point3d)

Rotates the circle around an axis that starts at the provided point.

---

Public Method

TangentAt

Circles use trigonometric parameterization: t -> center + cos(t)*radius*xaxis + sin(t)*radius*yaxis.

---

Public Method

ToNurbsCurve.

Constructs a nurbs curve representation of this circle. This amounts to the same as calling NurbsCurve.CreateFromCircle().

---

Public Method

ToNurbsCurve(Int32, Int32)

Create a uniform non-rational cubic NURBS approximation of a circle.

---

Public Method

ToString

Returns the fully qualified type name of this instance.

(Inherited from ValueType.)

---

Public Method
Transform

Transforms this circle using an transformation matrix.

---

Public Method

Translate

Moves the circle.

---

Public Method
Static Member

TryFitCircleToPoints

Attempt to fit a circle through a set of points.

---

Public Method
Static Member

TryFitCircleTT

Try to fit a circle to two curves using tangent relationships.

---

Public Method
Static Member

TryFitCircleTTT

Try to fit a circle to three curves using tangent relationships.

---

Public Method
Static Member

TrySmallestEnclosingCircle

Attempt to create the smallest circle enclosing a set of planar points.

---

Remarks

\>An IsValid circle has positive radius and an IsValid plane defining the frame.