Drawing The Geoms
At the end of the SimLoop function, after advancing the simulation one step and then deleting the contact joints, we called a function called DrawGeom. This function serves as a generic rendering routine for all types of geoms, using a different rendering function for each class of geom. In keeping with the examples that came with the ODE library, the DrawGeom function takes four parameters. The first is the geom's ID, then its position vector, rotation matrix and lastly a flag used to toggle the rendering of the geoms axis aligned bounding box.