I have some models moving around a sphere using glRotate() and glTranslate() which all works how I want. Now I need to add collision detection. Each model has a bounding box and bounding sphere associated with it. How do I keep track of each models' position and apply that to the bounding box and bounding sphere so that I can test for collisions? I am using Java on Android, with the libGDX framework on OpenGL ES 1.1.