public Point2D GetPointByOffset(double offset, bool isFromPoint1)
{
Point2D from = isFromPoint1 ? Point1 : Point2;
Point2D to = isFromPoint1 ? Point2 : Point1;
AbscissaDirection abscissaDirection = from.X.IsLessThanOrApproximatelyEqualTo(to.X) ? AbscissaDirection.LeftToRight : AbscissaDirection.RightToLeft;
OrdinateDirection ordinateDirection = from.Y.IsLessThanOrApproximatelyEqualTo(to.Y) ? OrdinateDirection.BottomToTop : OrdinateDirection.TopToBottom;
var point = LineEquation.GetPointByOffset(from, offset, abscissaDirection, ordinateDirection);
if (point is null)
{
throw new InvalidOperationException($"Cannot get point on line segment {this} by offset {offset}");
}
return(point.Value);
}
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)));
}
private void SetAxesDirections()
{
dynamic xLeft = default(dynamic);
dynamic yBottom = default(dynamic);
dynamic xRight = default(dynamic);
dynamic yTop = default(dynamic);
sheet.GetDrawingArea(ref xLeft, ref yBottom, ref xRight, ref yTop);
if (yTop < yBottom)
ordinateDirection = OrdinateDirection.TopToBottom;
else
ordinateDirection = OrdinateDirection.BottomToTop;
if (xLeft < xRight)
abscissaDirection = AbscissaDirection.LeftToRight;
else
abscissaDirection = AbscissaDirection.RightToLeft;
}
