public static double get_Distance(IndexPoint p1, IndexPoint p2)
{
if (p1 == null || p2 == null)
return double.NaN;
return get_Distance(p1.X, p1.Y, p2.X, p2.Y);
}
public void AddPoint(IndexPoint pt)
{
string cell = this.get_GridCell(pt.X, pt.Y);
this._points.Add(pt);
ArrayList theCellContents;
if (this._index.ContainsKey(cell) == false)
{
theCellContents = new ArrayList();
theCellContents.Add(this._points.Count - 1);
this._index.Add(cell, theCellContents);
}
else
{
theCellContents = (ArrayList)this._index[cell];
theCellContents.Add(this._points.Count - 1);
}
}
public ArrayList PointPairsWithinLimits(double lowLimit, double highLimit)
{
if (lowLimit >= highLimit)
return null;
ArrayList theReturn = new ArrayList();
for (int theIndex = 0; theIndex < this._points.Count; theIndex++)
{
IndexPoint thePoint = (IndexPoint)this._points[theIndex];
ArrayList theCells = this.get_GridCells(
thePoint.X - highLimit,
thePoint.Y - highLimit,
thePoint.X + highLimit,
thePoint.Y + highLimit);
foreach (object cell in theCells)
{
ArrayList theCellContents = (ArrayList)this._index[cell];
if (theCellContents != null)
{
for (int j = 0; j < theCellContents.Count; j++)
{
int theOtherIndex = (int)theCellContents[j];
// If theIndex is equal to theOtherIndex, it's the same point
// If theIndex is less than theOtherIndex, it's already been done
if (theOtherIndex > theIndex)
{
IndexPoint theOtherPoint = (IndexPoint)this._points[theOtherIndex];
double distance = get_Distance(thePoint, theOtherPoint);
if (lowLimit <= distance && distance <= highLimit)
{
// If the two points are from the same error feature (likely),
// check that they are at least two vertexes apart
bool bSpurious = false;
if (thePoint.SourceFeatureID == theOtherPoint.SourceFeatureID)
{
if (Math.Abs(thePoint.SourcePointIndex - theOtherPoint.SourcePointIndex) < 3)
{
bSpurious = true;
}
else
{
// The only case that we will accept is if theOtherPoint is closer to
// thePoint than the point immediately before it. i.e. the line has
// looped back and is approaching the original point
IndexPoint thePreviousPoint = (IndexPoint)this._points[theOtherIndex - 1];
double previousDistance = get_Distance(thePoint, thePreviousPoint);
if (previousDistance < distance)
{
bSpurious = true;
}
}
}
if (bSpurious == false)
{
/* Format of the result is IndexPoint[6]
* [0] - thePoint
* [1] - theOtherPoint
* [2] - point preceding thePoint in source feature shape
* [3] - point following thePoint in source feature shape
* [4] - point preceding theOtherPoint in source feature shape
* [5] - point following theOtherPoint in source feature shape
*/
IndexPoint[] thePair = new IndexPoint[6];
thePair[0] = thePoint;
thePair[1] = theOtherPoint;
if (theIndex > 0 && ((IndexPoint)this._points[theIndex-1]).SourceFeatureID == thePoint.SourceFeatureID)
thePair[2] = (IndexPoint)this._points[theIndex-1];
if (theIndex < this._points.Count - 1 && ((IndexPoint)this._points[theIndex+1]).SourceFeatureID == thePoint.SourceFeatureID)
thePair[3] = (IndexPoint)this._points[theIndex+1];
if (theOtherIndex > 0 && ((IndexPoint)this._points[theOtherIndex-1]).SourceFeatureID == theOtherPoint.SourceFeatureID)
thePair[4] = (IndexPoint)this._points[theOtherIndex-1];
if (theOtherIndex < this._points.Count - 1 && ((IndexPoint)this._points[theOtherIndex+1]).SourceFeatureID == theOtherPoint.SourceFeatureID)
thePair[5] = (IndexPoint)this._points[theOtherIndex+1];
theReturn.Add(thePair);
}
}
}
}
}
}
}
return theReturn;
}