/// <summary>
/// Copy constructor.
/// </summary>
/// <param name="v">A SpatialVector from which to copy</param>
public SpatialVector(SpatialVector v){
_x = v._x;
_y = v._y;
_z = v._z;
_ra = v._ra;
_dec = v._dec;
_okRaDec = v._okRaDec;
_okXYZ = v._okXYZ;
}
/// <summary>
/// Test whether or not point described by vector v is inside
/// this halfspace
/// </summary>
/// <param name="v">A point</param>
/// <returns>true if the specified point described by v is inside this halfspace</returns>
public bool contains(SpatialVector v) {
// v is inside the halfspace, if the angle between v and
// the direction vector is smaller than the cone half-angle.
// Note that _D = cos(half-angle)
//
return (v.dot(_SV) >= _D);
}
/// <summary>
/// Make a halfspace with parameters (V, D)
///
/// It is not necessary that the directional vector, though normal
/// to the cutting plane, by definition, be a normal vector.
/// </summary>
/// <param name="v">The cutting plane's normal vector</param>
/// <param name="d">The distance of the cutting plane along the normal
/// vector's direction. Can be negative.</param>
public Halfspace(SpatialVector v, double d) {
init();
if (d < -1.0) _D = -1.0;
else if (d > 1.0) _D = 1.0;
else _D = d;
_SV.assign(v);
_SV.normalizeMeSafely();
if (_D < -SpatialVector.Epsilon) {
_sign = Sign.Negative;
} else if (_D >= SpatialVector.Epsilon) {
_sign = Sign.Positive;
} else {
_sign = Sign.Zero;
}
_hangle = Math.Acos(_D);
}
/// <summary>
/// Allocate some internal veriables
/// </summary>
private void init(){
_ID = HtmState.Instance.newhs; // a unique ID for this halfspace
_D = 0.0;
_SV = new SpatialVector(0.0, 0.0, 1.0);
_West = new SpatialVector();
_hangle = SpatialVector.Pi / 2.0;
_sign = Sign.Zero;
}
/// <summary>
/// Perform cross prodcut of this and another
/// vector. Operation writes result into this vector
/// </summary>
/// <param name="that">The other vector</param>
public void crossMe(SpatialVector that){
Cartesian a = that;
this.crossMe(a);
}
/// <summary>
/// Perform dot product between this and another
/// vector.
/// </summary>
/// <param name="that">The other vector</param>
/// <returns>The dot product</returns>
public double dot(SpatialVector that){
Cartesian a = this;
Cartesian b = that;
return a.dot(b);
}
/// <summary>
/// Perform cross prodcut of this and another
/// vector. Operation returns a new instance of a
/// Cartesian.
/// </summary>
/// <param name="that">The other vector</param>
/// <returns>A new Cartesian</returns>
public Cartesian cross(SpatialVector that){
Cartesian a = this;
Cartesian b = that;
return a.cross(b);
}
