In the DrawStuff examples, there is a function setTransform that tranforms the rotation matrix and position vector from ODE format to openGl format. My question is, why do we need to do it? If ode's format is column-major and openGl is also column major, why do we need to transform 0 4 8 12 0 1 2 12 1 5 9 13 into 4 5 6 13 2 6 10 14 8 9 10 14 3 7 11 15 3 7 11 15 ?