/// <summary>
/// Remove the segs in the section of the line.
/// </summary>
/// <param name="line"></param>
/// <param name="start"></param>
/// <param name="end"></param>
private void Remove(TaggedLineString line, int start, int end)
{
for (int i = start; i < end; i++)
{
TaggedLineSegment seg = line.GetSegment(i);
_inputIndex.Remove(seg);
}
}
private void SimplifySection(int i, int j, int depth)
{
depth += 1;
int[] sectionIndex = new int[2];
if ((i + 1) == j)
{
LineSegment newSeg = _line.GetSegment(i);
_line.AddToResult(newSeg);
// leave this segment in the input index, for efficiency
return;
}
bool isValidToSimplify = true;
/**
* Following logic ensures that there is enough points in the output line.
* If there is already more points than the minimum, there's nothing to check.
* Otherwise, if in the worst case there wouldn't be enough points,
* don't flatten this segment (which avoids the worst case scenario)
*/
if (_line.ResultSize < _line.MinimumSize)
{
int worstCaseSize = depth + 1;
if (worstCaseSize < _line.MinimumSize)
{
isValidToSimplify = false;
}
}
double[] distance = new double[1];
int furthestPtIndex = FindFurthestPoint(_linePts, i, j, distance);
// flattening must be less than distanceTolerance
if (distance[0] > _distanceTolerance)
{
isValidToSimplify = false;
}
// test if flattened section would cause intersection
LineSegment candidateSeg = new LineSegment();
candidateSeg.P0 = _linePts[i];
candidateSeg.P1 = _linePts[j];
sectionIndex[0] = i;
sectionIndex[1] = j;
if (HasBadIntersection(_line, sectionIndex, candidateSeg))
{
isValidToSimplify = false;
}
if (isValidToSimplify)
{
LineSegment newSeg = Flatten(i, j);
_line.AddToResult(newSeg);
return;
}
SimplifySection(i, furthestPtIndex, depth);
SimplifySection(furthestPtIndex, j, depth);
}
