public override bool LogicalToLayerCoordinatesAndDirection(Logical3D r0, Logical3D r1, double t, out double ax, out double ay, out double adx, out double ady)
{
LogicalToLayerCoordinates(Logical3D.Interpolate(r0, r1, t), out ax, out ay);
LogicalToLayerCoordinates(r0, out var x0, out var y0);
LogicalToLayerCoordinates(r1, out var x1, out var y1);
adx = x1 - x0;
ady = y1 - y0;
return(true);
}
/// <summary>
/// Converts logical coordinates along an isoline to layer coordinates and returns the direction of the isoline at this point.
/// </summary>
/// <param name="r0">Logical starting point of the isoline.</param>
/// <param name="r1">Logical end point of the isoline.</param>
/// <param name="t">Parameter between 0 and 1 that determines the point on the isoline.
/// A value of 0 denotes the starting point of the isoline, a value of 1 the end point. The logical
/// coordinates are linear interpolated between starting point and end point.</param>
/// <param name="direction">Logical direction vector.</param>
/// <param name="normalizeddirection">Returns the normalized direction vector,i.e. a vector of norm 1, that
/// goes in the logical direction provided by the previous argument. </param>
/// <returns>The location (in layer coordinates) of the isoline point.</returns>
public virtual PointF GetNormalizedDirection(
Logical3D r0, Logical3D r1,
double t,
Logical3D direction,
out PointF normalizeddirection)
{
double ax, ay, adx, ady;
Logical3D rn0 = Logical3D.Interpolate(r0, r1, t);
Logical3D rn1 = rn0 + direction;
this.LogicalToLayerCoordinatesAndDirection(rn0, rn1, 0, out ax, out ay, out adx, out ady);
double hypot = Calc.RMath.Hypot(adx, ady);
if (0 == hypot)
{
// then we look a little bit displaced - we might be at the midpoint where the directions are undefined
double displT = t;
if (displT < 0.5)
{
displT += 1E-6;
}
else
{
displT -= 1E-6;
}
Logical3D displR = Logical3D.Interpolate(r0, r1, displT);
Logical3D displD = displR + direction;
double dummyx, dummyy;
LogicalToLayerCoordinatesAndDirection(displR, displD, 0, out dummyx, out dummyy, out adx, out ady);
hypot = Calc.RMath.Hypot(adx, ady);
}
// Normalize the vector
if (hypot > 0)
{
adx /= hypot;
ady /= hypot;
}
normalizeddirection = new PointF((float)adx, (float)ady);
return(new PointF((float)ax, (float)ay));
}
/// <summary>
/// Converts logical coordinates along an isoline to layer coordinates and returns the direction of the isoline at this point.
/// </summary>
/// <param name="r0">Logical starting point of the isoline.</param>
/// <param name="r1">Logical end point of the isoline.</param>
/// <param name="t">Parameter between 0 and 1 that determines the point on the isoline.
/// A value of 0 denotes the starting point of the isoline, a value of 1 the end point. The logical
/// coordinates are linear interpolated between starting point and end point.</param>
/// <param name="direction">Logical direction vector.</param>
/// <param name="normalizeddirection">Returns the normalized direction vector,i.e. a vector of norm 1, that
/// goes in the logical direction provided by the previous argument. </param>
/// <returns>The location (in layer coordinates) of the isoline point.</returns>
public virtual PointD3D GetPositionAndNormalizedDirection(
Logical3D r0, Logical3D r1,
double t,
Logical3D direction,
out VectorD3D normalizeddirection)
{
var rn0 = Logical3D.Interpolate(r0, r1, t);
Logical3D rn1 = rn0 + direction;
LogicalToLayerCoordinatesAndDirection(rn0, rn1, 0, out var pos, out var dir);
double hypot = dir.Length;
if (0 == hypot)
{
// then we look a little bit displaced - we might be at the midpoint where the directions are undefined
double displT = t;
if (displT < 0.5)
{
displT += 1E-6;
}
else
{
displT -= 1E-6;
}
var displR = Logical3D.Interpolate(r0, r1, displT);
Logical3D displD = displR + direction;
LogicalToLayerCoordinatesAndDirection(displR, displD, 0, out var dummyx, out dir);
hypot = dir.Length;
}
// Normalize the vector
if (hypot > 0)
{
dir /= hypot;
}
normalizeddirection = dir;
return(pos);
}
