/// <summary>
/// Devuelve el ángulo (en grados) entre v1 y v2.
/// <para>Ambos vectores se normalizan y quedan modificados.</para>
/// <para>Si uno de los vectores o los dos valen cero, devuelve 90º.</para>
/// <para>El ángulo devuelto varia entre 0 y 180 grados</para>
/// </summary>
/// <param name="v1"></param>
/// <param name="v2"></param>
/// <returns></returns>
public static double Angle(Vector3F v1, Vector3F v2)
{
v1.Normalize();
v2.Normalize();
var rdot = v1.Dot(v2);
var result = Math.Acos(rdot);
return(MathHelp.DegreesFromRadians((float)result));
}
/// <summary>
/// Construct a plane from 3 coplanar points.
/// </summary>
/// <param name="point0">First point.</param>
/// <param name="point1">Second point.</param>
/// <param name="point2">Third point.</param>
public Plane(Vector3F point0, Vector3F point1, Vector3F point2)
{
Normal = new Vector3F();
var edge1 = point1 - point0;
var edge2 = point2 - point0;
Vector3F.Cross(edge1, edge2, ref Normal);
Normal.Normalize();
D = -Normal.Dot(point0);
}
/// <summary>
/// This is a pseudodistance. The sign of the return value is
/// positive if the point is on the positive side of the plane,
/// negative if the point is on the negative side, and zero if the
/// point is on the plane.
/// The absolute value of the return value is the true distance only
/// when the plane normal is a unit length vector.
/// </summary>
/// <param name="point"></param>
/// <returns></returns>
public float GetDistance(Vector3F point)
{
return(Normal.Dot(point) + D);
}
public Plane(Vector3F normal, Vector3F point)
{
Normal = normal;
D = -normal.Dot(point);
}