//// temporary Coordinates to materialize points from the CoordinateSequence
//private readonly Coordinate _p0 = new Coordinate();
//private readonly Coordinate _p1 = new Coordinate();
//private readonly Coordinate _q0 = new Coordinate();
//private readonly Coordinate _q1 = new Coordinate();
private double ComputeLineLineDistance(FacetSequence facetSeq)
{
// both linear - compute minimum segment-segment distance
var minDistance = Double.MaxValue;
var p0 = new Coordinate();
var p1 = new Coordinate();
var q0 = new Coordinate();
var q1 = new Coordinate();
for (int i = _start; i < _end - 1; i++)
{
for (int j = facetSeq._start; j < facetSeq._end - 1; j++)
{
_pts.GetCoordinate(i, p0);
_pts.GetCoordinate(i + 1, p1);
facetSeq._pts.GetCoordinate(j, q0);
facetSeq._pts.GetCoordinate(j + 1, q1);
double dist = DistanceComputer.SegmentToSegment(p0, p1, q0, q1);
if (dist == 0.0)
{
return(0.0);
}
if (dist < minDistance)
{
minDistance = dist;
}
}
}
return(minDistance);
}
/// <summary>
///
/// </summary>
/// <param name="line0"></param>
/// <param name="line1"></param>
/// <param name="locGeom"></param>
private void ComputeMinDistance(ILineString line0, ILineString line1, GeometryLocation[] locGeom)
{
if (line0.EnvelopeInternal.Distance(line1.EnvelopeInternal) > _minDistance)
{
return;
}
var coord0 = line0.Coordinates;
var coord1 = line1.Coordinates;
// brute force approach!
for (int i = 0; i < coord0.Length - 1; i++)
{
for (int j = 0; j < coord1.Length - 1; j++)
{
double dist = DistanceComputer.SegmentToSegment(
coord0[i], coord0[i + 1],
coord1[j], coord1[j + 1]);
if (dist < _minDistance)
{
_minDistance = dist;
var seg0 = new LineSegment(coord0[i], coord0[i + 1]);
var seg1 = new LineSegment(coord1[j], coord1[j + 1]);
var closestPt = seg0.ClosestPoints(seg1);
locGeom[0] = new GeometryLocation(line0, i, closestPt[0]);
locGeom[1] = new GeometryLocation(line1, j, closestPt[1]);
}
if (_minDistance <= _terminateDistance)
{
return;
}
}
}
}
private double ComputeDistanceLineLine(FacetSequence facetSeq, GeometryLocation[] locs)
{
// both linear - compute minimum segment-segment distance
double minDistance = double.MaxValue;
for (int i = _start; i < _end - 1; i++)
{
var p0 = _pts.GetCoordinate(i);
var p1 = _pts.GetCoordinate(i + 1);
for (int j = facetSeq._start; j < facetSeq._end - 1; j++)
{
var q0 = facetSeq._pts.GetCoordinate(j);
var q1 = facetSeq._pts.GetCoordinate(j + 1);
double dist = DistanceComputer.SegmentToSegment(p0, p1, q0, q1);
if (dist < minDistance)
{
minDistance = dist;
if (locs != null)
{
UpdateNearestLocationsLineLine(i, p0, p1, facetSeq, j, q0, q1, locs);
}
if (minDistance <= 0)
{
return(minDistance);
}
}
}
}
return(minDistance);
}
/// <summary>
///
/// </summary>
/// <param name="line0"></param>
/// <param name="line1"></param>
/// <param name="locGeom"></param>
private void ComputeMinDistance(LineString line0, LineString line1, GeometryLocation[] locGeom)
{
if (line0.EnvelopeInternal.Distance(line1.EnvelopeInternal) > _minDistance)
{
return;
}
var coord0 = line0.Coordinates;
var coord1 = line1.Coordinates;
// brute force approach!
for (int i = 0; i < coord0.Length - 1; i++)
{
// short-circuit if line segment is far from line
var segEnv0 = new Envelope(coord0[i], coord0[i + 1]);
if (segEnv0.Distance(line1.EnvelopeInternal) > _minDistance)
{
continue;
}
for (int j = 0; j < coord1.Length - 1; j++)
{
// short-circuit if line segments are far apart
var segEnv1 = new Envelope(coord1[j], coord1[j + 1]);
if (segEnv0.Distance(segEnv1) > _minDistance)
{
continue;
}
double dist = DistanceComputer.SegmentToSegment(
coord0[i], coord0[i + 1],
coord1[j], coord1[j + 1]);
if (dist < _minDistance)
{
_minDistance = dist;
var seg0 = new LineSegment(coord0[i], coord0[i + 1]);
var seg1 = new LineSegment(coord1[j], coord1[j + 1]);
var closestPt = seg0.ClosestPoints(seg1);
locGeom[0] = new GeometryLocation(line0, i, closestPt[0]);
locGeom[1] = new GeometryLocation(line1, j, closestPt[1]);
}
if (_minDistance <= _terminateDistance)
{
return;
}
}
}
}
public void TestRandomDisjointCollinearSegments()
{
int n = 1000000;
int failCount = 0;
for (int i = 0; i < n; i++)
{
//System.out.println(i);
var seg = RandomDisjointCollinearSegments();
if (0 == DistanceComputer.SegmentToSegment(seg[0], seg[1], seg[2], seg[3]))
{
/*
* System.out.println("FAILED! - "
+ WKTWriter.toLineString(seg[0], seg[1]) + " - "
+ WKTWriter.toLineString(seg[2], seg[3]));
*/
failCount++;
}
}
Console.WriteLine("# failed = " + failCount + " out of " + n);
}
/// <summary>
/// Computes the distance between this line segment and another one.
/// </summary>
/// <param name="ls"></param>
/// <returns></returns>
public double Distance(LineSegment ls)
{
return(DistanceComputer.SegmentToSegment(_p0, _p1, ls._p0, ls._p1));
}
public void TestDistanceLineLineDisjointCollinear()
{
Assert.AreEqual(1.999699, DistanceComputer.SegmentToSegment(
new Coordinate(0, 0), new Coordinate(9.9, 1.4),
new Coordinate(11.88, 1.68), new Coordinate(21.78, 3.08)), 0.000001);
}