private static bool intersectPolyline(RectangleF rect, Path path)
{
Node prev = null;
foreach(object i in path.content)
{
if(i is Node)
{
Node curr = (Node)i;
if(rect.Contains((float)(curr.lon), (float)curr.lat))
return true;
if(prev!= null)
{
Line2D line = new Line2D(new PointD(prev.lon, prev.lat), new PointD(curr.lon, curr.lat));
if(line.intersects(rect))
return true;
}
prev = curr;
}
}
return false;
}
private static List<Point> douglasPeucker(List<Point> pts, double dist)
{
int n = pts.Count;
if (n <= 2)
return pts;
Line2D line = new Line2D(pts[0].point, pts[pts.Count - 1].point);
double maxDist = Double.NegativeInfinity;
int best = -1;
for (int i = 1; i < n - 1; i++)
{
double temp = line.ptLineDist(pts[i].point);
if (maxDist < temp)
{
maxDist = temp;
best = i;
}
}
List<Point> result = new List<Point>();
if (maxDist < dist)
{
result.Add(pts[0]);
result.Add(pts[pts.Count - 1]);
return result;
}
List<Point> part1 = new List<Point>();
for (int i = 0; i <= best; i++)
{
part1.Add(pts[i]);
}
result.AddRange(douglasPeucker(part1, dist));
result.Remove(result[result.Count - 1]);
List<Point> part2 = new List<Point>();
for (int i = best; i < n; i++)
{
part2.Add(pts[i]);
}
result.AddRange(douglasPeucker(part2, dist));
return result;
}