public static void LengthArc_Returns_Curve_Line_Distance_Between_Offset_Points_of_Specified_Radius(double angleRadians, double radius, double expectedResult)
{
Angle angle1 = new Angle(0);
Angle angle2 = new Angle(angleRadians);
AngularOffset offset = new AngularOffset(angle1, angle2);
Assert.AreEqual(expectedResult, offset.LengthArc(radius), Tolerance);
}
//TODO Useful? Not used yet
///// <summary>
///// The length between the provided points along a circular curve, assumed to be about the origin.
///// </summary>
///// <param name="pointI">Point i.</param>
///// <param name="pointJ">Point j.</param>
///// <returns>System.Double.</returns>
//public static double LengthBetween(CartesianCoordinate pointI, CartesianCoordinate pointJ)
//{
// AngularOffset angle = AngularOffset.CreateFromPoints(pointI, CartesianCoordinate.Origin(), pointJ);
// double radius = pointI.OffsetFrom(CartesianCoordinate.Origin()).Length();
// return LengthBetween(angle, radius);
//}
///// <summary>
///// The length between the provided points along a circular curve.
///// </summary>
///// <param name="pointI">Point i.</param>
///// <param name="pointJ">Point j.</param>
///// <param name="radius">Arc radius</param>
///// <returns>System.Double.</returns>
//public static double LengthBetween(CartesianCoordinate pointI, CartesianCoordinate pointJ, double radius)
//{
// IntersectionCircularCircular intersection = new IntersectionCircularCircular(
// new CircularCurve(radius, pointI),
// new CircularCurve(radius, pointJ));
// // Shape is symmetric, so it doesn't matter if the 1st or 2nd intersection coordinate is taken.
// CartesianCoordinate center = intersection.IntersectionCoordinates()[0];
// AngularOffset angle = AngularOffset.CreateFromPoints(pointI, center, pointJ);
// return LengthBetween(angle, radius);
//}
/// <summary>
/// The length within the provided rotation along a circular curve.
/// </summary>
/// <param name="rotation">Rotation to get arc length between.</param>
/// <param name="radius">Arc radius</param>
/// <returns>System.Double.</returns>
public static double LengthBetween(AngularOffset rotation, double radius)
{
double length = rotation.LengthArc(radius);
return((length.IsZeroSign(rotation.Tolerance) && !rotation.Delta().Radians.IsZeroSign(rotation.Tolerance)) ?
Numbers.TwoPi * radius :
length);
}