Randy, thanks for your tips. Randall Hopper writes: > |Is there a way to export the ribbon two-sided, with > |different colors to VRML? > > I'm not sure but I think VRML's in the same boat. You could repeat > geometry with different colors using backface culling (solid TRUE), but > it's a hack.
I don't understand what you mean with `solid TRUE'. Does this refer to DX (I can find neither `solid' in this sense, nor even the term `backface culling' in the docs) or to VRML? Please bear with my ignorance, as I am hardly familiar with VRML and just use it to eventually import DX objects into Povray. > It's unfortunate DX doesn't have a more useful export route for renderable > fields than VRML (which many tools can write but few tools can read) like > 3D Studio or OpenFlight. We occasionally wish for that around here too. > However, PolyTrans now allegedly parses VRML very well, so that may be a > good route if the VRML exporter is beefed up a bit (however, I haven't > tried Polytrans' VRML support personally). > > An alternative might be to check out Richard Gillilan's RIB export module > for DX: > > ftp://ftp.tc.cornell.edu/pub/Data.Explorer/by_discipline/chemistry > > You could use BMRT for your ray tracing, or PRMan or another Renderman > renderer if global illumination isn't a requirement. > This isn't to imply that no other RIB renderers besides BMRT support > global illumination. See: > > http://www.dotcsw.com/links.html > http://www.exluna.com/products/links.html I am probably too conservative to switch renderers, now that I can do a few basic things in this one (Povray). For my application, I have solved the problem by a macro that draws the Ribbon twice, displacing it once with RubberSheet. [I have no clue what field the RubberSheet deforms here, but it works; I suppose one could also shift the ribbon with Compute, using the FaceNormals to get the direction.] This has the additional advantage that I also get the two different colors in hardware rendering, but of course it uses twice as much resources and is a kind of kludge. W o l f g a n g
