/// <summary>
/// Finds the nearest point to the requested location that is within the tolerance radius.
/// </summary>
/// <param name="ProjectedRadius">The tolerance radius in projected units used to search for the nearest point that can be snapped to. </param>
/// <param name="x">x coordinate in projected map units</param>
/// <param name="y">y coordinate in projected map units</param>
/// <param name="BestPoint">A PointD class with the location of the nearest point to snap to if there is are any within the tolerance, null if no points are found.</param>
/// <returns>Returns true if there is a point to snap to.</returns>
public bool CanSnap(double ProjectedRadius, double x, double y, ref System.Collections.ArrayList BestPoints)
{
PointD BestPoint = null;
System.Collections.IDictionaryEnumerator ie = m_lists.GetEnumerator();
while (ie.MoveNext())
{
int snaplayeridx = (int)ie.Key;
if (((System.Collections.SortedList)m_lists[snaplayeridx]).Count == 0)
{
continue;
}
try
{
double val = (x - ProjectedRadius);
int first = FindFirst(((System.Collections.SortedList)m_lists[snaplayeridx]), val);
double bestX = x + ProjectedRadius, bestY = y + ProjectedRadius;
double curX;
if (first == -1)
{
System.Diagnostics.Debug.WriteLine("Could not find any points to snap to");
return(false);
}
curX = (double)((System.Collections.SortedList)m_lists[snaplayeridx]).GetKey(first);
while (curX < (x + ProjectedRadius))
{
if (Math.Abs(curX - x) < Math.Abs(bestX - x))
{ // the current x is closer to the x value than the previous best
// now we think we have a new best x, try to find a better y value
System.Collections.SortedList tList = (System.Collections.SortedList)((System.Collections.SortedList)m_lists[snaplayeridx]).GetByIndex(first);
for (int j = 0; j < tList.Count; j++)
{
double curY = (double)tList.GetKey(j);
if (Math.Abs(curY - y) < Math.Abs(bestY - y))
{ // the current y is closer to the y value than the previous best
BestPoint = new PointD(curX, curY);
if (BestPoints == null)
{
BestPoints = new System.Collections.ArrayList();
}
BestPoints.AddRange((System.Collections.ArrayList)tList.GetByIndex(j));
// only reset the bestX and bestY when both are better than the previous.
bestX = curX;
bestY = curY;
}
}
}
first++;
if (first < ((System.Collections.SortedList)m_lists[snaplayeridx]).Count)
{
curX = (double)((System.Collections.SortedList)m_lists[snaplayeridx]).GetKey(first);
}
else
{
break;
}
}
}
catch (System.Exception ex)
{
errCnt++;
System.Diagnostics.Debug.WriteLine(errCnt + " " + ex.Message);
}
}
if (BestPoints == null)
{
return(false);
}
else
{
return(true);
}
}
/// <summary>
/// Finds the nearest point to the requested location that is within the tolerance radius.
/// </summary>
/// <param name="ProjectedRadius">The tolerance radius in projected units used to search for the nearest point that can be snapped to.</param>
/// <param name="x">x coordinate in projected map units</param>
/// <param name="y">y coordinate in projected map units</param>
/// <param name="curShape">The shape that is currently being created. Points from this shape are also checked.</param>
/// <param name="BestPoint">A PointD class with the location of the nearest point to snap to if there is are any within the tolerance, null if no points are found.</param>
/// <returns>Returns true if there is a point to snap to.</returns>
public bool CanSnap(double ProjectedRadius, double x, double y, ShapeClass curShape, ref System.Collections.ArrayList BestPoints)
{
System.Collections.IDictionaryEnumerator ie = m_lists.GetEnumerator();
PointD myBest = null;
System.Collections.ArrayList myBestPoints = null;
while (ie.MoveNext())
{
int snaplayeridx = (int)ie.Key;
// find any points that are within the tolerance in curShape.
for (int i = 0; i < curShape.NumPoints; i++)
{
PointD pt = curShape[i];
double d = pt.Dist(x, y);
if (d < ProjectedRadius)
{
if (myBest != null)
{
if (d < myBest.Dist(x, y))
{
myBest = pt;
}
}
else
{
myBest = pt;
}
}
}
if (myBest != null)
{
SnapData d = new SnapData(-1, -1, myBest);
myBestPoints = new System.Collections.ArrayList();
myBestPoints.Add(d);
}
if (CanSnap(ProjectedRadius, x, y, ref BestPoints))
{ // work with that best point.
if (myBest != null)
{
PointD tPoint = ((SnapData)BestPoints[0]).point;
if (myBest.Dist(x, y) < tPoint.Dist(x, y))
{
if (BestPoints == null)
{
BestPoints = new System.Collections.ArrayList();
}
BestPoints.AddRange(myBestPoints);
}
}
}
else
{
if (myBestPoints != null)
{
if (BestPoints == null)
{
BestPoints = new System.Collections.ArrayList();
}
BestPoints.AddRange(myBestPoints);
}
}
}
if (BestPoints == null)
{
return(false);
}
else
{
return(true);
}
}
