Blitz3D C++ geometry code

Flying Willy, See the matrix class. My guess is that this is the quat to euler rotation matrix conversion. (as below - the matrix itself is defined as the three vectors, i,j,k)

Sweenie, I do not use C++ (seems I am going to have to make the effort - if only to make sense of this sort of stuff) but maybe the code is using this to implicitly cast a quat to a matrix?

  	Matrix( const Quat &q ){
		float xx=q.v.x*q.v.x,yy=q.v.y*q.v.y,zz=q.v.z*q.v.z;
		float xy=q.v.x*q.v.y,xz=q.v.x*q.v.z,yz=q.v.y*q.v.z;
		float wx=q.w*q.v.x,wy=q.w*q.v.y,wz=q.w*q.v.z;
		i=Vector( 1-2*(yy+zz),2*(xy-wz),2*(xz+wy) ),
		j=Vector( 2*(xy+wz),1-2*(xx+zz),2*(yz-wx) ),
		k=Vector( 2*(xz-wy),2*(yz+wx),1-2*(xx+yy) );
        }

There is also some stuff on the code archives dealing with quats. Not tested though, I have never used them directly.