I have constructed a twisted ribbon where the two sides are nicely distinguished by setting front and back colors to yellow and blue, respectively. This works fine with software rendering, while hardware renders the ribbon all in yellow (maybe Mesa or OpenGL have no notion of a two-sided surface??), which doesn't really bother me. What bothers me however is that I would like to export the ribbon to VRML, convert the .wrl file with vrml2pov and render it with Povray using textures, complex lighting, etc. But both, my VRML viewers and Povray just show the ribbon in yellow, so I suppose the VRML file has already lost the second color (or the two-sidedness).
My question is thus: Is there a way to export the ribbon two-sided, with different colors to VRML? If not, I suppose I will have to add a second, slightly shifted ribbon of the other color. What is the easiest way of doing so, as I have to shift the second ribbon in a varying direction (the normal of the ribbon)? W o l f g a n g D o b l e r -- ------------------------------------------------------------------------- | Wolfgang Dobler Phone: ++49/(0)761/3198-224 | | Kiepenheuer Institute for Solar Physics Fax: ++49/(0)761/3198-111 | | Schöneckstraße 6 | | D-79104 Freiburg E-Mail: [EMAIL PROTECTED] | | Germany http://www.kis.uni-freiburg.de/~dobler/ | -------------------------------------------------------------------------
