Epilog with 3 dimensional graphics primitives

*To*: mathgroup at smc.vnet.net*Subject*: [mg83672] Epilog with 3 dimensional graphics primitives*From*: Barrow <GRseminar at gmail.com>*Date*: Wed, 28 Nov 2007 05:27:18 -0500 (EST)

Dear all, I wanna plot a torus on which shows the definition of parameters. That is, there is a torus ((R+r*Cos[u])Cos[v],(R +r*Sin[u])*Sin[v],r*Sin[u]), I wanna show the definitions of u and v. So I have to draw some circles, lines on the torus. My idea is: ParametricPlot3D[{(5 + 2 Cos[u]) Cos[v], (5 + 2 Cos[u]) Sin[v], 2 Sin[u]}, {u,0,2Pi},{v,0,2Pi}, Epilog->{Line and Circle here}] There are two problems. The first is that, I tried to put in the Epilog above some 3D graphics primitive, e.g. Point[{0,0,0}]. But it doesn't work! It seems that only 2D graphics primitives can be put inside the Epilog. The second problem is that, I wanna show the definitions of u and v, so the torus should be "transparent" in some section to show the lines and circles (i.e. to show the definitions of u and v), how can I do that? i.e. to make some portion of the torus being transparent? Thank you all! Sincerely Barrow