public Point2D GetPointByDistance(double x, double distance, AbscissaDirection direction)
{
if (distance.IsApproximately(0.0))
{
return(new Point2D(x, CalculateY(x)));
}
if (distance.IsLessThanOrApproximatelyEqualTo(0.0))
{
distance = Math.Abs(distance);
direction = direction == AbscissaDirection.LeftToRight ? AbscissaDirection.RightToLeft : AbscissaDirection.LeftToRight;
}
var xDistance = Math.Sqrt(distance.Square() / (Slope.Square() + 1));
var x1 = x - xDistance;
var x2 = x + xDistance;
var pointX = direction == AbscissaDirection.LeftToRight
? (x1.IsGreaterThanOrApproximatelyEqualTo(x) ? x1 : x2)
: (x1.IsLessThanOrApproximatelyEqualTo(x) ? x1 : x2);
return(new Point2D(pointX, CalculateY(pointX)));
}