Provides access to members that control properties of circular arcs.

#### Product Availability

#### Description

A CircularArc is an object that describes any portion of a circle. The size of the CircularArc is determined by the length of the Radius and the Central Angle. CircularArcs can be constructed by numerous different methods given a wide variety of input parameters. A CircularArc differs from an EllipticArc in that every point along the CircularArc must be a fixed distance (the Radius) from the CenterPoint.

#### Members

Description |
||
---|---|---|

CenterPoint | The center point. | |

CentralAngle | The included (or central) angle. | |

ChordHeight | The chord height (assigning preserves endpoints, and orientation unless chord height is < 0). | |

Complement | Changes this arc into its complement; 'from' and 'to' points are unchanged. | |

Dimension | The topological dimension of this geometry. | |

Envelope | Creates a copy of this geometry's envelope and returns it. | |

FromAngle | The angle, measured from a horizontal line through this circular arc's center point, that defines where this arc starts. | |

FromPoint | The 'from' point of the curve. | |

GeometryType | The type of this geometry. | |

GeoNormalize | Shifts longitudes, if need be, into a continuous range of 360 degrees. | |

GeoNormalizeFromLongitude | Normalizes longitudes into a continuous range containing the longitude. This method is obsolete. | |

GetSubcurve | Extracts a portion of this curve into a new curve. | |

IsClosed | Indicates if 'from' and 'to' points (of each part) are identical. | |

IsCounterClockwise | Indicates if this circular is oriented counter-clockwise from its 'from' point to its 'to' point. | |

IsEmpty | Indicates whether this geometry contains any points. | |

IsLine | Indicates if the arc has degenerated to a line (radius is infinite). | |

IsMinor | Indicates whether this circular arc is a minor arc or a major arc. | |

IsPoint | Indicates if the arc has degenerated to a point (radius is 0). | |

Length | The length of the curve. | |

Project | Projects this geometry into a new spatial reference. | |

PutCoords | Defines this arc by a center point, 'from' and 'to' points, and orientation. If the from and to points do not lie on the same circle, the arc's center point will be adjusted. | |

PutCoordsByAngle | Defines this circular arc by a center point, 'from' angle, signed central angle, and radius. | |

PutRadiusByPoint | Defines the radius of this circular arc to be the distance from the arc's center point to the input point; other properties remain unchanged. | |

QueryCenterPoint | Copies the center point of this circular arc to the input point. | |

QueryCoords | Copies the center, 'from' and 'to' points, orientation and major/minor property into the input parameters. | |

QueryCoordsByAngle | Returns the center point, 'from' angle, signed central angle, and radius. | |

QueryEnvelope | Copies this geometry's envelope properties into the specified envelope. | |

QueryFromPoint | Copies this curve's 'from' point to the input point. | |

QueryNormal | Constructs a line normal to a curve from a point at a specified distance along the curve. | |

QueryPoint | Copies to outPoint the properties of a point on the curve at a specified distance from the beginning of the curve. | |

QueryPointAndDistance | Finds the point on the curve closest to inPoint, then copies that point to outPoint; optionally calculates related items. | |

QueryTangent | Constructs a line tangent to a curve from a point at a specified distance along the curve. | |

QueryToPoint | Copies the curve's 'to' point into the input point. | |

Radius | The radius. | |

ReverseOrientation | Reverses the parameterization of the curve ('from' point becomes 'to' point, first segment becomes last segment, etc). | |

SetEmpty | Removes all points from this geometry. | |

SnapToSpatialReference | Moves points of this geometry so that they can be represented in the precision of the geometry's associated spatial reference system. | |

SpatialReference | The spatial reference associated with this geometry. | |

ToAngle | The angle, measured from a horizontal line through this circular arc's center point, that defines where this arc ends. | |

ToPoint | The 'to' point of the curve. |

#### Inherited Interfaces

Interfaces | Description |
---|---|

ICurve | Provides access to properties and methods of all 1 dimensional curves (polylines, segments, boundaries of polygons, etc.). |

IGeometry | Provides access to members that describe properties and behavior of all geometric objects. |

#### CoClasses that implement ICircularArc

CoClasses and Classes | Description |
---|---|

CircularArc | A portion of a circle that connects two points optionally has measure, height and ID attributes at each endpoint. |

#### Remarks

private void OutputArcProperties(ICircularArc circularArc)

{

String report = "Center Point: (" + circularArc.CenterPoint.X + ", " +

circularArc.CenterPoint.Y + ")" + "\n" +

"From Point: (" + circularArc.FromPoint.X + ", " +

circularArc.FromPoint.Y + ")" + "\n" +

"To Point: (" + circularArc.ToPoint.X + ", " +

circularArc.ToPoint.Y + ")" + "\n" +

"From Angle: " + circularArc.FromAngle + "\n" +

"Central Angle: " + circularArc.CentralAngle + "\n" +

"To Angle: " + circularArc.ToAngle + "\n" +

"Radius: " + circularArc.Radius + "\n" +

"Chord Height: " + circularArc.ChordHeight + "\n" +

"IsCounterClockwise: " + circularArc.IsCounterClockwise + "\n" +

"IsMinor: " + circularArc.IsMinor + "\n" +

"IsLine: " + circularArc.IsLine + "\n" +

"IsPoint: " + circularArc.IsPoint + ")";

//IsLine and IsPoint check for degenerate cases of CircularArcs

System.Windows.Forms.MessageBox.Show(report);

}

#### See Also

IPoint Interface | IGeometry Interface | ISegment Interface | IConstructCircularArc Interface