Hello This is my first post, and I hope I'm not in the wrong forum. I'm a CG artist working for the film and animation industry. I'm currently programming (in my spare time) a free tool for animator, that give the ability to edit the animation curves directly in 3d in a bi-directional way. You can see a short demo here: vimeo.com/20538565 It's working quite fine, but now I would like to push it forward and give the ability to display and edit the curve's tangents! Unfortunately I just can't get it...Currently, I'm evaluating the global I have three bezier curves, one for each axis of a cartesian 3d space, that represents a translation in time. I need to convert the tangent handles ( P1 and P2 for a 4 point bezier curve) X,Y values of each axis into 3D positions that will give me the ability to rebuild a curve in 3D. I hope my explanations are not too confuse. Kind regards.