public static double GetSpin(this System.Windows.Media.Media3D.Matrix3D matrix)
{
// get the rotatoin about the Z`` axis: angle between localX and tiltedX
Vector3D localX = matrix.Transform(new System.Windows.Media.Media3D.Vector3D(1, 0, 0));
Matrix3D tiltMatrix = new System.Windows.Media.Media3D.Matrix3D()
.SetOrientation(matrix.GetOrientation())
.SetTilt(matrix.GetTilt());
Vector3D tiltedX = tiltMatrix.Transform(new System.Windows.Media.Media3D.Vector3D(1, 0, 0));
double multiplier = 1.0;
Vector3D zcross = Vector3D.CrossProduct(tiltedX, localX);
if (zcross.Z < 0)
{
multiplier = -1.0;
}
return(System.Windows.Media.Media3D.Vector3D.AngleBetween(localX, tiltedX) * multiplier);
}
public static System.Windows.Media.Media3D.Matrix3D SetOrientation(this System.Windows.Media.Media3D.Matrix3D matrix, double orientationDegrees)
{
Vector3D translation = new System.Windows.Media.Media3D.Vector3D(matrix.OffsetX, matrix.OffsetY, matrix.OffsetZ);
// backoff translation
matrix.Translate(new System.Windows.Media.Media3D.Vector3D(-translation.X, -translation.Y, -translation.Z));
// back off any existing Z rotation
matrix.Rotate(new System.Windows.Media.Media3D.Quaternion(new System.Windows.Media.Media3D.Vector3D(0, 0, 1), matrix.GetOrientation() * -1.0));
matrix.Rotate(new System.Windows.Media.Media3D.Quaternion(new System.Windows.Media.Media3D.Vector3D(0, 0, 1), orientationDegrees));
// add back translation
matrix.Translate(translation);
return(matrix);
}
public static double GetTilt(this System.Windows.Media.Media3D.Matrix3D matrix)
{
// get the rotation about the X` local axis
Vector3D localX = matrix.Transform(new System.Windows.Media.Media3D.Vector3D(1, 0, 0));
Vector3D localY = matrix.Transform(new System.Windows.Media.Media3D.Vector3D(0, 1, 0));
Matrix3D orientMatrix = new System.Windows.Media.Media3D.Matrix3D().SetOrientation(matrix.GetOrientation());
Vector3D orientedY = orientMatrix.Transform(new System.Windows.Media.Media3D.Vector3D(0, 1, 0));
double multiplier = 1.0;
Vector3D xcross = Vector3D.CrossProduct(orientedY, localY);
double xangle = Vector3D.AngleBetween(localX, xcross);
if (xangle > 90.0)
{
multiplier = -1.0;
}
//if(xcross.X < 0.0) { multiplier = -1.0; }
// rotation about the X' axis = angle between localY and orientedY
double angle = System.Windows.Media.Media3D.Vector3D.AngleBetween(localY, orientedY) * multiplier;
return(angle);
}
