/**
* Calculates whether the measures in the CoordinateSequence are monotone
* and strict monotone. The strict parameter indicates whether the
* determination should apply the definition of "strict monotonicity" or
* non-strict.
*
* @see #IsMonotone()
* @see #isStrictMonotone()
*/
private void DetermineMonotone()
{
this.monotone = true;
this.strictMonotone = true;
if (!this.IsEmpty)
{
double[] m = this.GetMeasures();
// short circuit if the first value is NaN
if (Double.IsNaN(m[0]))
{
this.monotone = false;
this.strictMonotone = false;
}
else
{
int result = 0;
int prevResult = 0;
for (int i = 1; i < m.Length && this.monotone; i++)
{
result = DoubleComparator.Compare(m[i - 1], m[i]);
this.monotone = !(result * prevResult < 0 || Double.IsNaN(m[i]));
this.strictMonotone &= this.monotone && result != 0;
prevResult = result;
}
}
}
// if not monotone, then certainly not strictly monotone
Debug.Assert(!(this.strictMonotone && !this.monotone));
}
public bool Equals3DWithMeasure(Coordinate other)
{
bool result = this.Equals3D(other);
if (result)
{
MCoordinate mc = ConvertCoordinate(other);
result = (DoubleComparator.Compare(M, mc.M) == 0);
}
return(result);
}
public MLineString UnionM(MLineString l)
{
if (!this.monotone || !l.monotone)
{
throw new ApplicationException("MGeometryException.OPERATION_REQUIRES_MONOTONE");
}
Coordinate[] linecoar = l.Coordinates;
if (l.GetMeasureDirection() == MGeometryType.Decreasing)
{
CoordinateArrays.Reverse(linecoar);
}
Coordinate[] thiscoar = this.Coordinates;
if (this.GetMeasureDirection() == MGeometryType.Decreasing)
{
CoordinateArrays.Reverse(thiscoar);
}
// either the last coordinate in thiscoar Equals the first in linecoar;
// or the last in linecoar Equals the first in thiscoar;
MCoordinate lasttco = (MCoordinate)thiscoar[thiscoar.Length - 1];
MCoordinate firsttco = (MCoordinate)thiscoar[0];
MCoordinate lastlco = (MCoordinate)linecoar[linecoar.Length - 1];
MCoordinate firstlco = (MCoordinate)linecoar[0];
MCoordinate[] newcoar = new MCoordinate[thiscoar.Length
+ linecoar.Length - 1];
if (lasttco.Equals2D(firstlco) &&
DoubleComparator.Equals(lasttco.M, firstlco.M))
{
Array.Copy(thiscoar, 0, newcoar, 0, thiscoar.Length);
Array.Copy(linecoar, 1, newcoar, thiscoar.Length,
linecoar.Length - 1);
}
else if (lastlco.Equals2D(firsttco) &&
DoubleComparator.Equals(lastlco.M, firsttco.M))
{
Array.Copy(linecoar, 0, newcoar, 0, linecoar.Length);
Array.Copy(thiscoar, 1, newcoar, linecoar.Length,
thiscoar.Length - 1);
}
else
{
throw new ApplicationException("MGeometryException.UNIONM_ON_DISJOINT_MLINESTRINGS");
}
ICoordinateSequence mcs = this.Factory.CoordinateSequenceFactory.Create(newcoar);
MLineString returnmlinestring = new MLineString(mcs, this.Factory);
Debug.Assert(returnmlinestring.IsMonotone(false), "new UnionM-ed MLineString is not monotone");
return(returnmlinestring);
}
/**
* Assigns the first coordinate in the CoordinateSequence to the
* <code>beginMeasure</code> and the last coordinate in the
* CoordinateSequence to the <code>endMeasure</code>. Measure values for
* intermediate coordinates are then interpolated proportionally based on
* their 2d offset of the overall 2d length of the LineString.
* <p>
* If the beginMeasure and endMeasure values are equal it is assumed that
* all intermediate coordinates shall be the same value.
*
* @param beginMeasure
* Measure value for first coordinate
* @param endMeasure
* Measure value for last coordinate
*/
public void Interpolate(double beginMeasure, double endMeasure)
{
if (this.IsEmpty)
{
return;
}
// interpolate with first vertex = beginMeasure; last vertex =
// endMeasure
Coordinate[] coordinates = this.Coordinates;
double length = this.Length;
double mLength = endMeasure - beginMeasure;
double d = 0;
bool continuous = DoubleComparator.Equals(beginMeasure, endMeasure);
double m = beginMeasure;
MCoordinate prevCoord = MCoordinate.ConvertCoordinate(coordinates[0]);
prevCoord.M = m;
MCoordinate curCoord;
for (int i = 1; i < coordinates.Length; i++)
{
curCoord = MCoordinate.ConvertCoordinate(coordinates[i]);
if (continuous)
{
curCoord.M = beginMeasure;
}
else
{
d += curCoord.Distance(prevCoord);
m = beginMeasure + (d / length) * mLength;
curCoord.M = m;
prevCoord = curCoord;
}
}
this.GeometryChanged();
Debug.Assert(this.IsMonotone(false), "interpolate function should always leave IMGeometry monotone");
}
/*
* (non-Javadoc)
*
* @see org.hibernatespatial.mgeom.IMGeometry#GetCoordinatesBetween(double,double)
*/
public ICoordinateSequence[] GetCoordinatesBetween(double fromM, double toM)
{
if (!this.IsMonotone(false))
{
throw new ApplicationException("MGeometryException.OPERATION_REQUIRES_MONOTONE");
}
if (this.IsEmpty || !this.IsMonotone(false))
{
return(new MCoordinateSequence[0]);
}
else
{
double[] mval = this.GetMeasures();
// determin upper and lower boundaries for the MLineString Measures
double lb = Math.Min(mval[0], mval[mval.Length - 1]);
double up = Math.Max(mval[0], mval[mval.Length - 1]);
// set fromM and toM to maximal/minimal values when they exceed
// lowerbound-upperbound
fromM = Math.Max(lb, Math.Min(fromM, up));
toM = Math.Max(lb, Math.Min(toM, up));
// if at this point the fromM and toM are equal, then return an
// empty MCoordinateSequence
if (DoubleComparator.Equals(fromM, toM))
{
return(new MCoordinateSequence[0]);
}
MCoordinate[] mcoords = (MCoordinate[])this.Coordinates;
// ensure that we traverse the coordinate array in ascending M-order
if (GetMeasureDirection() == MGeometryType.Decreasing)
{
CoordinateArrays.Reverse(mcoords);
}
double minM = Math.Min(fromM, toM);
double maxM = Math.Max(fromM, toM);
List <MCoordinate> mcolist = new List <MCoordinate>();
for (int i = 0; i < mcoords.Length; i++)
{
if (mcolist.Count == 0 && mcoords[i].M >= minM)
{
MCoordinate mco2 = mcoords[i];
if (DoubleComparator.Equals(mcoords[i].M, minM))
{
mcolist.Add(mco2);
}
else
{
MCoordinate mco1 = mcoords[i - 1];
double r = (minM - mco1.M) / (mco2.M - mco1.M);
Debug.Assert(DoubleComparator.Equals(mco1.M + r * (mco2.M - mco1.M), minM), "Error on assumption on r");
MCoordinate mc = new MCoordinate(
mco1.X + r * (mco2.X - mco1.X),
mco1.Y + r * (mco2.Y - mco1.Y),
mco1.Z + r * (mco2.Z - mco1.Z),
minM);
mcolist.Add(mc);
}
}
else if (mcoords[i].M >= minM && mcoords[i].M <= maxM)
{
mcolist.Add(mcoords[i]);
if (DoubleComparator.Equals(mcoords[i].M, maxM))
{
break;
}
}
else if (mcoords[i].M > maxM)
{
// mcoords[i] > Math.max(fromM, toM
Debug.Assert(i > 0, "mistaken assumption");
MCoordinate mco2 = mcoords[i];
MCoordinate mco1 = mcoords[i - 1];
double r = (maxM - mco1.M) / (mco2.M - mco1.M);
MCoordinate mc = new MCoordinate(
mco1.X + r * (mco2.X - mco1.X),
mco1.Y + r * (mco2.Y - mco1.Y),
mco1.Z + r * (mco2.Z - mco1.Z),
maxM
);
mcolist.Add(mc);
break;
}
}
// copy over, but only to the length of numPnts
MCoordinate[] h = new MCoordinate[mcolist.Count];
for (int i = 0; i < mcolist.Count; i++)
{
h[i] = (MCoordinate)mcolist[i];
}
if (!DoubleComparator.Equals(minM, fromM))
{
CoordinateArrays.Reverse(h);
}
MCoordinateSequence mc2 = new MCoordinateSequence(h);
return(new MCoordinateSequence[] { mc2 });
}
}
