NURBS means "Non-Uniform Rational B-Splines". In short, NURBS can be used to build rounded faces by transfering only very few data. A mathematical formula is used to construct the faces.
NurbsSurface (and other Nurbs objects) are part of the
ISO/IEC14772-1:1997/Amd. 1:2002(E) VRML standard. Some VRML97 browsers like
cc3d or cortona already have the NurbsSurface Node available, while most
other browsers
do not support it yet.
White_dune support the VRML Amendment 1 NurbsSurface, but this would be useless
for other browsers.
For the Cosmo Player browser (at least the version 2.1.5 on IRIX and
and the version 2.1.1 on M$Windows), it is possible to use
a NurbsSurface PROTO written in
javascript to make use of the NurbsSurface node (texCoord not supported yet).
To view NurbsSurface nodes with the Cosmo Player browser
you need to include this EXTERNPROTO declaration
in your VRML file (e.g. by using File -> import in white_dune).
Other Browsers with NurbsSurface support will fall back to their
own (very much faster) implementation.
Click here (and be patient till
the accounting is ready) if you have the Cosmo Player browser
(at least the version 2.1.5 on IRIX or version 2.1.1 on M$Windows work)
to see a example of the usage of the NurbsSurface EXTERNPROTO.