public static double AngleBetweenVectors(this IMathVector v0, IMathVector v1)
{
if (((double[])v0.ArrayData).Length == ((double[])v1.ArrayData).Length)
{
var sign = Math.Sign(((IMathVector)(v0.Cross(v1))).ArrayData.CastArray <double>()[2]);
var ret = Math.Acos(v0.Dot(v1) / (v0.GetLength() * v1.GetLength()));
return(sign * ret);
}
throw new Exception("Vectors must have the same dimension!");
}
public IMathTransform GetTransformBetweenVectorsAroundPoint(
double[] vec1, double[] vec2, double[] pt)
{
IMathVector mathVec1 = m_MathUtils.CreateVector(vec1) as IMathVector;
IMathVector mathVec2 = m_MathUtils.CreateVector(vec2) as IMathVector;
IMathVector crossVec = mathVec1.Cross(mathVec2) as IMathVector;
double dot = mathVec1.Dot(mathVec2);
double vec1Len = mathVec1.GetLength();
double vec2Len = mathVec2.GetLength();
double angle = Math.Acos(dot / vec1Len * vec2Len);
IMathPoint mathPt = m_MathUtils.CreatePoint(pt) as IMathPoint;
return(m_MathUtils.CreateTransformRotateAxis(mathPt, crossVec, angle) as IMathTransform);
}
public TransformationMaxtrix GetTransformBetweenVectorsAroundPoint(
Vector firstVector, Vector secondVector, Point point)
{
IMathVector mathVec1 = (m_MathUtils.CreateVector(firstVector.ToArray()) as IMathVector).Normalise();
IMathVector mathVec2 = (m_MathUtils.CreateVector(secondVector.ToArray()) as IMathVector).Normalise();
IMathVector crossVec = (mathVec1.Cross(mathVec2) as IMathVector).Normalise();
double dot = mathVec1.Dot(mathVec2);
double vec1Len = mathVec1.GetLength();
double vec2Len = mathVec2.GetLength();
double angle = System.Math.Acos(dot / vec1Len * vec2Len);
IMathPoint mathPt = m_MathUtils.CreatePoint(point.ToArray()) as IMathPoint;
var mathTransform = m_MathUtils.CreateTransformRotateAxis(mathPt, crossVec, angle) as IMathTransform;
return(mathTransform.ToTransformationMaxtrix());
}
/// <summary>
/// a X b => 投影到 b
/// gives the multiplier for b which would be the projection of a on b
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static double Project(this IMathVector a, IMathVector b)
{
return(a.Dot(b) / (b.Dot(b)));
}
private double GetAngle(IMathVector vec1, IMathVector vec2)
{
return(Math.Acos(vec1.Dot(vec2) / (vec1.GetLength() * vec2.GetLength())));
}
/// <summary>
/// gives the multiplier for b which would be the projection of a on b
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static double Project(this IMathVector a, IMathVector b)
{
return a.Dot(b)/(b.Dot(b));
}
public static double GetAngle(this IMathVector vec1, IMathVector vec2)
{
return(Math.Acos(vec1.Dot(vec2) / (vec1.GetLength() * vec2.GetLength())));
}