/// <summary>
/// Calculates position of the closest point on the line to the passed point
/// </summary>
/// <param name="point">Passed point that will be snapped</param>
/// <param name="snappedPointType">Precalculated snapping type (from the distance method)</param>
/// <returns>Position of closest point</returns>
/// <exception cref="ArgumentOutOfRangeException">Invalid snapped point type</exception>
public Vector3 ClosestPoint(Vector3 point, SnappedPointType snappedPointType)
{
switch (snappedPointType)
{
case SnappedPointType.InBetween:
var x = (b * (b * point.x - a * point.z) - a * c) / a2b2;
var z = (a * (-b * point.x + a * point.z) - b * c) / a2b2;
return(new Vector3(x, point.y, z));
case SnappedPointType.Start:
return(new Vector3(start.x, point.y, start.z));
case SnappedPointType.End:
return(new Vector3(end.x, point.y, end.z));
default:
throw new ArgumentOutOfRangeException(nameof(snappedPointType), snappedPointType, null);
}
}
/// <summary>
/// Calculates distance to the line, returns float.MaxValue is greater than passed max distance
/// </summary>
/// <param name="point">Point that will be snapped to line</param>
/// <param name="maxDistance">Maximal distance that can be applied</param>
/// <param name="snappedPointType">Returns type how point will be snapped to the line</param>
/// <returns>Distance between the point and the line, returns float.MaxValue is greater than passed max distance</returns>
public float Distance(Vector3 point, float maxDistance, out SnappedPointType snappedPointType)
{
var distanceToStraightLine = Mathf.Abs((a * point.x + b * point.z + c) / sqrta2b2);
if (distanceToStraightLine > maxDistance)
{
snappedPointType = SnappedPointType.Invalid;
return(float.MaxValue);
}
var pointStart = Distance(point, start);
var pointEnd = Distance(point, end);
var lengthPow = Mathf.Pow(length, 2);
var pointStartPow = Mathf.Pow(pointStart, 2);
var pointEndPow = Mathf.Pow(pointEnd, 2);
//Check if point will be snapped to the start, end or in between
//Point is snapped to point between start and end only when the formed triangle is obtuse
if (pointStartPow > lengthPow + pointEndPow)
{
if (pointEnd > maxDistance)
{
snappedPointType = SnappedPointType.Invalid;
return(float.MaxValue);
}
snappedPointType = SnappedPointType.End;
return(pointEnd);
}
if (pointEndPow > lengthPow + pointStartPow)
{
if (pointStart > maxDistance)
{
snappedPointType = SnappedPointType.Invalid;
return(float.MaxValue);
}
snappedPointType = SnappedPointType.Start;
return(pointStart);
}
snappedPointType = SnappedPointType.InBetween;
return(distanceToStraightLine);
}
