internal virtual int Find_prev_non_degenerate(com.epl.geometry.SegmentIterator segIter, int index)
{
segIter.ResetToVertex(index, -1);
while (segIter.HasPreviousSegment())
{
com.epl.geometry.Segment segment = segIter.PreviousSegment();
double length = segment.CalculateLength2D();
if (length != 0)
{
return(segIter.GetStartPointIndex());
}
}
return(-1);
}