public static System.Windows.Media.Media3D.Matrix3D SetTilt(
this System.Windows.Media.Media3D.Matrix3D matrix, double tilt)
{
Vector3D translation = new System.Windows.Media.Media3D.Vector3D(matrix.OffsetX, matrix.OffsetY, matrix.OffsetZ);
/*
* var orientation = matrix.GetOrientation();
* var spin = matrix.GetSpin();
*
* var newMatrix = new Matrix3D();
* newMatrix = newMatrix.RotateOTS(new Vector3D(orientation, tilt,spin));
* newMatrix.Translate(translation);
* return newMatrix;*/
// backoff translation
matrix.Translate(new System.Windows.Media.Media3D.Vector3D(-translation.X, -translation.Y, -translation.Z));
Vector3D localX = matrix.Transform(new System.Windows.Media.Media3D.Vector3D(1, 0, 0));
// backoff exiting tilt
matrix.Rotate(new System.Windows.Media.Media3D.Quaternion(localX, matrix.GetTilt() * -1.0));
matrix.Rotate(new System.Windows.Media.Media3D.Quaternion(localX, tilt));
// add back translation
matrix.Translate(translation);
return(matrix);
}
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);
}
