private static LineString linearZInterpolation ( LineString lineString ) { double startz = lineString . getStartPoint ( ) . getCoordinate ( ) . z ; double endz = lineString . getEndPoint ( ) . getCoordinate ( ) . z ; if ( Double . isNaN ( startz ) || Double . isNaN ( endz ) ) { return lineString ; } else { double length = lineString . getLength ( ) ; lineString . apply ( new LinearZInterpolationFilter ( startz , endz , length ) ) ; return lineString ; } }
Interpolate a linestring according the start and the end coordinates z value . If the start or the end z is NaN return the input linestring