/// <summary>
/// Finds the distance from the triangle to a line segment
/// </summary>
public double DistanceFrom(LineSegment segment)
{
if (Intersects(segment))
{
return(0);
}
var nearestPointInPlane = ContainingPlane.NearestPoint(segment);
if (IsInside(nearestPointInPlane))
{
return(ContainingPlane.Distance(segment));
}
var line1 = new LineSegment(Points[0], Points[1]);
var line2 = new LineSegment(Points[1], Points[2]);
var line3 = new LineSegment(Points[2], Points[0]);
double p1 = segment.DistanceSquared(line1);
double p2 = segment.DistanceSquared(line2);
double p3 = segment.DistanceSquared(line3);
double minDistance2 = UtilityFunctions.Min(p1, p2, p3);
return(Math.Sqrt(minDistance2));
}
/// <summary>
/// Whether a given line segment intersects the triangle
/// </summary>
public bool Intersects(LineSegment segment)
{
if (!ContainingPlane.Intersects(segment))
{
return(false);
}
var point = ContainingPlane.Intersection(segment.UnderlyingLine);
return(IsInside(point));
}
/// <summary>
/// Returns whether a point known to be in the containing plane lies inside the triangle
/// </summary>
private bool IsInside(Point point)
{
var rotatedPoint = ContainingPlane.TransformTo2D(point);
return(RotatedTriangle.Inside(rotatedPoint));
}
