/// <summary>
/// Create Quadrilateral.
/// </summary>
/// <param name="a">Lenth of side a.</param>
/// <param name="b">Lenth of side b.</param>
/// <param name="c">Lenth of side c.</param>
/// <param name="d">Lenth of side d.</param>
/// <returns>New quadrilateral.</returns>
public static Quadrilateral WithFourSides(double a, double b, double c, double d)
{
Checks.GreaterThanZero(a, nameof(a));
Checks.GreaterThanZero(b, nameof(b));
Checks.GreaterThanZero(c, nameof(c));
Checks.GreaterThanZero(d, nameof(d));
var quad = new Quadrilateral();
quad.SideA = a;
quad.SideB = b;
quad.SideC = c;
quad.SideD = d;
var e = Triangle.Right.Hypotenuse(c, d);
var ad1 = Converter.RadiansToDegrees(Math.Asin(c / e));
var cb1 = 90 - ad1;
var ad2 = Triangle.Angle(quad.SideA, e, quad.SideB);
var cb2 = Triangle.Angle(quad.SideB, e, quad.SideA);
quad.AngleAD = ad1 + ad2;
quad.AngleCB = cb1 + cb2;
quad.AngleBA = 270 - quad.AngleAD - quad.AngleCB;
return(quad);
}
/// <summary>
/// Create Quadrilateral.
/// </summary>
/// <param name="a">Lenth of side a.</param>
/// <param name="b">Lenth of side b.</param>
/// <param name="ad">AD angle in degrees.</param>
/// <param name="ba">BA angle in degrees.</param>
/// <returns>New quadrilateral.</returns>
public static Quadrilateral WithTwoSidesTwoAngles(double a, double b, double ad, double ba)
{
Checks.GreaterThanZero(a, nameof(a));
Checks.GreaterThanZero(b, nameof(b));
Checks.Between(ad, 0, 360, nameof(ad));
Checks.Between(ba, 0, 360, nameof(ba));
var quad = new Quadrilateral();
quad.SideA = a;
quad.SideB = b;
quad.AngleAD = ad;
quad.AngleBA = ba;
quad.AngleCB = 270 - quad.AngleAD - quad.AngleBA;
var bx = Triangle.Right.Opposite(quad.SideB, quad.AngleCB);
var by = Triangle.Right.Side(quad.SideB, bx);
var ay = Triangle.Right.Opposite(quad.SideA, quad.AngleAD);
quad.SideC = Quadrilateral.CalculateC(quad.AngleCB, ay, by);
var ax = Triangle.Right.Side(quad.SideA, ay);
quad.SideD = Quadrilateral.CalculateD(quad.AngleAD, ax, bx);
return(quad);
}
/// <summary>
/// Calculates hypotenuse of right triangle from sides using Pythagorean theorem.
/// https://en.wikipedia.org/wiki/Pythagorean_theorem.
/// </summary>
/// <param name="sideA">Opposite side length.</param>
/// <param name="sideB">Side length.</param>
/// <returns>Hypotenuse length.</returns>
public static double Hypotenuse(double sideA, double sideB)
{
Checks.GreaterThanZero(sideA, nameof(sideA));
Checks.GreaterThanZero(sideB, nameof(sideB));
var hypotenuse = Math.Sqrt(sideA * sideA + sideB * sideB);
return(hypotenuse);
}
/// <summary>
/// Calculates side of right triangle from hypotenuse and side using Pythagorean theorem.
/// https://en.wikipedia.org/wiki/Pythagorean_theorem.
/// </summary>
/// <param name="hypotenuse">Hypotenuse length.</param>
/// <param name="side">Adjacent side length.</param>
/// <returns>Another side length.</returns>
public static double Side(double hypotenuse, double side)
{
Checks.GreaterThanZero(hypotenuse, nameof(hypotenuse));
Checks.GreaterThanZero(side, nameof(side));
var anotherSide = Math.Sqrt(hypotenuse * hypotenuse - side * side);
return(anotherSide);
}
/// <summary>
/// Calculate angle from hypotenuse and opposite.
/// </summary>
/// <param name="hypotenuse">Hypotenuse length.</param>
/// <param name="opposite">Opposite length.</param>
/// <returns>Angle in degrees.</returns>
public static double Angle(double hypotenuse, double opposite)
{
Checks.GreaterThanZero(hypotenuse, nameof(hypotenuse));
Checks.GreaterThanZero(hypotenuse, nameof(opposite));
var angle = Converter.RadiansToDegrees(Math.Asin(hypotenuse / opposite));
return(angle);
}
/// <summary>
/// Calculate opposite from hypotenuse and angle.
/// https://keisan.casio.com/exec/system/1273849674.
/// </summary>
/// <param name="hypotenuse">Hypotenuse length.</param>
/// <param name="angle">Angle in degrees.</param>
/// <returns>Opposite length.</returns>
public static double Base(double hypotenuse, double angle)
{
Checks.GreaterThanZero(hypotenuse, nameof(hypotenuse));
Checks.Between(angle, -360, 360, nameof(angle));
var baseSide = hypotenuse * Math.Cos(Converter.DegreesToRadians(angle));
return(baseSide);
}
/// <summary>
/// Calculate opposite from hypotenuse and angle.
/// https://keisan.casio.com/exec/system/1273849674.
/// </summary>
/// <param name="hypotenuse">Hypotenuse length.</param>
/// <param name="angle">Angle in degrees.</param>
/// <returns>Opposite length.</returns>
public static double Opposite(double hypotenuse, double angle)
{
Checks.GreaterThanZero(hypotenuse, nameof(hypotenuse));
Checks.Between(angle, -360, 360, nameof(angle));
var opposite = hypotenuse * Math.Sin(Converter.DegreesToRadians(angle));
return(opposite);
}
/// <summary>
/// Calculates opposite side when angle and two sides are known.
/// </summary>
/// <param name="sideA">Side length.</param>
/// <param name="sideB">Side length.</param>
/// <param name="angle">Angle in degrees.</param>
/// <returns>Opposite side to an angle length.</returns>
public static double Opposite(double sideA, double sideB, double angle)
{
Checks.GreaterThanZero(sideA, nameof(sideA));
Checks.GreaterThanZero(sideB, nameof(sideB));
Checks.Between(angle, 0, 180, nameof(angle));
var opposite = Math.Sqrt(sideA * sideA + sideB * sideB - 2 * sideA * sideB * Math.Cos(Converter.DegreesToRadians(angle)));
return(opposite);
}
/// <summary>
/// Calculates angle when all sides are known.
/// </summary>
/// <param name="sideA">Side length.</param>
/// <param name="sideB">Side length.</param>
/// <param name="opposite">Opposite side to an angle length.</param>
/// <returns>Angle in degrees.</returns>
public static double Angle(double sideA, double sideB, double opposite)
{
Checks.GreaterThanZero(sideA, nameof(sideA));
Checks.GreaterThanZero(sideB, nameof(sideB));
Checks.GreaterThanZero(opposite, nameof(opposite));
var radians = Math.Acos((sideA * sideA + sideB * sideB - opposite * opposite) / (2 * sideA * sideB));
var angle = Converter.RadiansToDegrees(radians);
return(angle);
}
/// <summary>
/// Calculate d side.
/// </summary>
/// <param name="ad">AD angle in degrees.</param>
/// <param name="ax">Lenth of side a_x.</param>
/// <param name="bx">Lenth of side b_x.</param>
/// <returns></returns>
private static double CalculateD(double ad, double ax, double bx)
{
Checks.Between(ad, -90, 180, nameof(ad));
Checks.GreaterThanZero(ax, nameof(ax));
Checks.GreaterThanZero(bx, nameof(bx));
if (ad < 90)
{
var d = bx + ax;
return(Math.Abs(d));
}
else if (ad == 90)
{
var d = bx;
return(Math.Abs(d));
}
else // alpha > 90
{
var d = bx - ax;
return(Math.Abs(d));
}
}
/// <summary>
/// Calculate c side.
/// </summary>
/// <param name="cb">CB angle in degrees.</param>
/// <param name="ay">Lenth of side a_y.</param>
/// <param name="by">Lenth of side b_y.</param>
/// <returns></returns>
private static double CalculateC(double cb, double ay, double by)
{
Checks.Between(cb, -90, 180, nameof(cb));
Checks.GreaterThanZero(ay, nameof(ay));
Checks.GreaterThanZero(by, nameof(by));
if (cb < 90)
{
var c = ay + by;
return(Math.Abs(c));
}
else if (cb == 90)
{
var c = ay;
return(Math.Abs(c));
}
else // beta > 90
{
var c = ay - by;
return(Math.Abs(c));
}
}