public double DistanceTo(Segment3d s)
{
if (this.Center.ProjectionTo(s.ToLine).BelongsTo(s))
{
return(this.DistanceTo(s.ToLine));
}
else
{
return(Min(this.DistanceTo(s.P1), this.DistanceTo(s.P2)));
}
}
/// <summary>
/// Return Axis Aligned Bounding Box (AABB) in given coordinate system.
/// </summary>
public Box3d BoundingBox(Coord3d coord = null)
{
coord = (coord == null) ? Coord3d.GlobalCS : coord;
Line3d l1 = new Line3d(coord.Origin, coord.Xaxis);
Line3d l2 = new Line3d(coord.Origin, coord.Yaxis);
Line3d l3 = new Line3d(coord.Origin, coord.Zaxis);
Segment3d s1 = this.ProjectionTo(l1);
Segment3d s2 = this.ProjectionTo(l2);
Segment3d s3 = this.ProjectionTo(l3);
return(new Box3d(_point, s1.Length, s2.Length, s3.Length, coord));
}
/// <summary>
/// Return Axis Aligned Bounding Box (AABB) in given coordinate system.
/// </summary>
public Box3d BoundingBox(Coord3d coord = null)
{
coord = (coord == null) ? Coord3d.GlobalCS : coord;
Line3d l1 = new Line3d(coord.Origin, coord.Xaxis);
Line3d l2 = new Line3d(coord.Origin, coord.Yaxis);
Line3d l3 = new Line3d(coord.Origin, coord.Zaxis);
double px, py, pz, lx, ly, lz;
Segment3d s = this.ProjectionTo(l1);
px = (0.5 * (s.P1 + s.P2)).ConvertTo(coord).X;
lx = s.Length;
s = this.ProjectionTo(l2);
py = (0.5 * (s.P1 + s.P2)).ConvertTo(coord).Y;
ly = s.Length;
s = this.ProjectionTo(l3);
pz = (0.5 * (s.P1 + s.P2)).ConvertTo(coord).Z;
lz = s.Length;
return(new Box3d(new Point3d(px, py, pz, coord), lx, ly, lz, coord));
}
/// <summary>
/// Determines whether two objects are equal.
/// </summary>
public override bool Equals(object obj)
{
if (obj == null || (!object.ReferenceEquals(this.GetType(), obj.GetType())))
{
return(false);
}
Segment3d s = (Segment3d)obj;
if (GeometRi3D.UseAbsoluteTolerance)
{
return((this.P1 == s.P1 && this.P2 == s.P2) | (this.P1 == s.P2 && this.P2 == s.P1));
}
else
{
double tol = GeometRi3D.Tolerance;
GeometRi3D.Tolerance = tol * this.Length;
GeometRi3D.UseAbsoluteTolerance = true;
bool result = (this.P1 == s.P1 && this.P2 == s.P2) | (this.P1 == s.P2 && this.P2 == s.P1);
GeometRi3D.UseAbsoluteTolerance = false;
GeometRi3D.Tolerance = tol;
return(result);
}
}
/// <summary>
/// Shortest distance between line and segment
/// </summary>
public double DistanceTo(Segment3d s)
{
return(s.DistanceTo(this));
}
/// <summary>
/// Returns shortest distance between two segments
/// </summary>
public double DistanceTo(Segment3d s)
{
// Algorithm by Dan Sunday
// http://geomalgorithms.com/a07-_distance.html
double small = GeometRi3D.Tolerance;
Vector3d u = this.ToVector;
Vector3d v = s.ToVector;
Vector3d w = new Vector3d(s.P1, this.P1);
double a = u * u;
double b = u * v;
double c = v * v;
double d = u * w;
double e = v * w;
double DD = a * c - b * b;
double sc = 0;
double sN = 0;
double sD = 0;
double tc = 0;
double tN = 0;
double tD = 0;
sD = DD;
tD = DD;
if (DD < small)
{
// the lines are almost parallel, force using point Me.P1 to prevent possible division by 0.0 later
sN = 0.0;
sD = 1.0;
tN = e;
tD = c;
}
else
{
// get the closest points on the infinite lines
sN = (b * e - c * d);
tN = (a * e - b * d);
if ((sN < 0.0))
{
// sc < 0 => the s=0 edge Is visible
sN = 0.0;
tN = e;
tD = c;
}
else if ((sN > sD))
{
// sc > 1 => the s=1 edge Is visible
sN = sD;
tN = e + b;
tD = c;
}
}
if ((tN < 0.0))
{
// tc < 0 => the t=0 edge Is visible
tN = 0.0;
// recompute sc for this edge
if ((-d < 0.0))
{
sN = 0.0;
}
else if ((-d > a))
{
sN = sD;
}
else
{
sN = -d;
sD = a;
}
}
else if ((tN > tD))
{
// tc > 1 => the t=1 edge Is visible
tN = tD;
// recompute sc for this edge
if (((-d + b) < 0.0))
{
sN = 0;
}
else if (((-d + b) > a))
{
sN = sD;
}
else
{
sN = (-d + b);
sD = a;
}
}
// finally do the division to get sc And tc
sc = Abs(sN) < small ? 0.0 : sN / sD;
tc = Abs(tN) < small ? 0.0 : tN / tD;
// get the difference of the two closest points
Vector3d dP = w + (sc * u) - (tc * v);
// = S1(sc) - S2(tc)
return(dP.Norm);
}
