/// <summary>
/// Find the closest point on a line segment specified by start and end points to
/// a test point.
/// </summary>
/// <param name="startPt">The start point of the line</param>
/// <param name="endPt">The end point of the line</param>
/// <param name="testPt">The point from which the distance is to be checked</param>
/// <returns></returns>
public static double ClosestParameter(Vector startPt, Vector endPt, Vector testPt)
{
Vector direction = endPt - startPt;
double t = Axis.ClosestParameter(startPt, direction, testPt);
if (t < 0)
{
return(0);
}
else if (t > 1.0)
{
return(1);
}
else
{
return(t);
}
}
/// <summary>
/// Find the closest point on a line segment specified by start and end points to
/// a test point.
/// </summary>
/// <param name="startPt">The start point of the line</param>
/// <param name="endPt">The end point of the line</param>
/// <param name="testPt">The point from which the distance is to be checked</param>
/// <returns></returns>
public static Vector ClosestPoint(Vector startPt, Vector endPt, Vector testPt)
{
Vector direction = endPt - startPt;
double t = Axis.ClosestParameter(startPt, direction, testPt);
if (t < 0)
{
return(startPt);
}
else if (t > 1.0)
{
return(endPt);
}
else
{
return(startPt + direction * t);
}
}
/// <summary>
/// Find the closest point on this line to a ray, expressed as a parameter
/// from 0-1 (Start-End)
/// </summary>
/// <param name="ray"></param>
/// <returns></returns>
public override double ClosestParameter(Axis ray, out double tRay)
{
tRay = ray.ClosestParameter(StartPoint, EndPoint - StartPoint, out double t);
t = t.Limit(0, 1);
return(t);
}