quatToMatrix

1 auto q = rquat.fromAngle( PI_2, vec3(0,0,1) );
2 
3 auto m = quatToMatrix(q);
4 auto r = mat3(0,-1, 0, 1, 0, 0, 0, 0, 1);
5 assert( eq_approx( m, r, 1e-7 ) );