/// <summary>
/// Extend this line to meet (as closely as possible) another.
/// The start or end vertex of this line (whichever will result in the smallest
/// overall movement) will be moved to meet the other at the closest point.
/// </summary>
/// <param name="other"></param>
/// <returns></returns>
public bool ExtendToLine(Line other)
{
Vector pt = Axis.ClosestPoint(StartPoint, Direction, other.StartPoint, other.Direction);
if (pt.IsValid())
{
double t = ClosestParameter(pt);
if (t < 0.5)
{
Start.Position = pt;
}
else
{
End.Position = pt;
}
return(true);
}
else
{
return(false);
}
}
/// <summary>
/// Calculate the data needed for initialising a circle from 3 points
/// </summary>
/// <param name="pt0"></param>
/// <param name="pt1"></param>
/// <param name="pt2"></param>
/// <returns></returns>
private static Vector[] Calculate3PtCSystem(ref Vector pt0, ref Vector pt1, ref Vector pt2, ref double radius)
{
Vector v01 = (pt1 - pt0);
Vector v12 = (pt2 - pt1);
//Find mid-points
Vector mid01 = pt0.Interpolate(pt1, 0.5);
Vector mid12 = pt1.Interpolate(pt2, 0.5);
Vector normal = v01.Cross(v12).Unitize();
//Find perpendicular axes
Vector axis1 = v01.Cross(normal);
Vector axis2 = v12.Cross(normal);
//FInd intersection:
Vector origin = Axis.ClosestPoint(mid01, axis1, mid12, axis2);
Vector vO0 = pt0 - origin;
radius = vO0.Magnitude();
if (radius == 0)
{
return new Vector[] { pt0, Vector.UnitZ, Vector.UnitX }
}
; //Zero-radius circle!
return(new Vector[] { origin, normal, vO0 / radius });
}
