Please make sure, you arrange your parameters like this:
Longitude 1, Latitude 1, Altitude 1 (optional), Longitude 2, Latitude 2, Altitude 2 (optional)
You can either specify 4 or 6 parameters
If you are using the default constructor with two dimensional positions (lng + lat only), please use the constructor like this:
BBox(lng1, lat1, lng2, lat2);
Takes a line, at a start point startPt, and a stop point stopPt
and returns a subsection of the line in-between those points.
The start & stop points don't need to fall exactly on the line.