Note that firstly it always returns the positive real quaternion (positive w)
Note also that it will sometimes slightly differ from the results of the other methods because it assumes that the input matrix really is a rotation matrix - if it isn't, e.g. because of rounding error, then the output quaternion will be very slightly different. For example, the test matrix
0 1 0 0
1 0 0 0
0 0 0.999999 0
0 0 0 1
will return 0.707107 0.707107 0.0005033 0.0005033
whereas the previous methods return 0.707107 0.707107 0.0 0.0
However, since quaternions are rotations, the meaning of how to convert a matrix that isn't a rotation is a little unclear..."
change of ' ' to GUIEventAdapter::KEY_Space, fix to url in Matrix_implementation.cpp.
Syntax fixes by Robert Osfield to above submission fix inconsistencies with normal
OSG coding style.
matrixd. It was returning the values of the diagonal
of the matrix, which only returns the scale if there
is not a rotation. I fixed this by returning the
length of the vectors that form the basis.
I also added a function to orthonormalize the
rotation component of the matrix. I seem to always run
into situations where non uniform (or even uniform)
scale complicate my calculations, and I thought other
members of the community could use this function as
well."