public static void simplifyDPStep(NFP points, int first, int last, double?sqTolerance, NFP simplified)
{
var maxSqDist = sqTolerance;
var index = -1;
var marked = false;
for (var i = first + 1; i < last; i++)
{
var sqDist = getSqSegDist(points[i], points[first], points[last]);
if (sqDist > maxSqDist)
{
index = i;
maxSqDist = sqDist;
}
}
if (maxSqDist > sqTolerance || marked)
{
if (index - first > 1)
{
simplifyDPStep(points, first, index, sqTolerance, simplified);
}
simplified.push(points[index]);
if (last - index > 1)
{
simplifyDPStep(points, index, last, sqTolerance, simplified);
}
}
}
// simplification using Ramer-Douglas-Peucker algorithm
public static NFP simplifyDouglasPeucker(NFP points, double?sqTolerance)
{
var last = points.Length - 1;
var simplified = new NFP();
simplified.AddPoint(points[0]);
simplifyDPStep(points, 0, last, sqTolerance, simplified);
simplified.push(points[last]);
return(simplified);
}