/// <summary>
/// Constructor that does the same as CoordinateSystem.AtParameter but that it checks if the z-axis is
/// in the same general direction as the given upVector. If not, it flips the z-axis to make it point
/// in the same overall direction as the upVector and also flips the y-axis accordingly to preserve
/// the right-handed CoordinateSystem rule.
/// </summary>
/// <param name="contextCurve"></param>
/// <param name="t"></param>
/// <param name="upVector"></param>
/// <returns></returns>
public static CoordinateSystem AtParameter(Curve contextCurve, double t, Vector upVector)
{
if (contextCurve == null)
throw new System.ArgumentNullException("contextCurve");
else if (upVector == null)
throw new System.ArgumentNullException("upVector");
else if (upVector.IsZeroVector())
throw new System.ArgumentException(string.Format(Properties.Resources.IsZeroVector, "up vector"), "upVector");
var cs = contextCurve.CoordinateSystemAtParameterCore(t, upVector);
if (null == cs)
throw new System.Exception(string.Format(Properties.Resources.OperationFailed, "CoordinateSystem.AtParameter"));
// property assigments
//
cs.ContextCurve = contextCurve;
cs.T = t;
cs.Distance = contextCurve.DistanceAtParameter(t);
cs.UpVector = upVector;
return cs;
}
/// <summary>
/// Constructs a a CoordinateSystem with its origin at the given parameter on the given curve. Its x-axis is tangential to the curve,
/// y-axis is along the normal and z-axis is along bi-normal at that point. This method is complementary to the
/// CoordinateSystemAtParameterAlongCurve() method in Curve class and has consistent behavior.
/// </summary>
/// <param name="contextCurve"></param>
/// <param name="t"></param>
/// <returns></returns>
public static CoordinateSystem AtParameter(Curve contextCurve, double t)
{
if (contextCurve == null)
throw new System.ArgumentNullException("contextCurve");
var cs = contextCurve.CoordinateSystemAtParameterCore(t, null);
if (null == cs)
throw new System.Exception(string.Format(Properties.Resources.OperationFailed, "CoordinateSystem.AtParameter"));
cs.ContextCurve = contextCurve;
cs.T = t;
cs.Distance = contextCurve.DistanceAtParameter(t);
return cs;
}
