The GRASPweb software
is widely used in the structural biology community. It is mainly
useful for generating contact surfaces of macromolecules (proteins, nucleic
acids) with associated biophysical properties such as electrostatic potentials.
This software takes advantage of SGI platforms capabilities for displaying.
However for publication purposes one may want to produce high-quality pictures,
e.g. featuring projected shadows, object texturing, and so on. Although GRASP
does not (yet) provide direct support for any external rendering softwares, the
molecular surfaces it generates can be saved in binary files for later use.
POV-Rayweb is a famous,
powerful and freely available software that renders photorealistic
pictures on numerous architectures. It actually has become a real standard in
many different fields, so that more and more softwares provide support for
it. The POV-Ray syntax is text-based, that means portable and convenient in
most cases. Unfortunately this is not efficient when parsing huge objects.
For instance, molecular surface may be described as meshes consisting of
thousands of triangles with their own textures. Furthermore, POV-Ray does not
provide a built-in feature to do color interpolation within triangles, a
feature that is commonly used to smooth different colors on the surface.
While some scripts like the TRIMAP.MCR macro from
the Chris Colefax's POV-Ray Include Files Pageweb allow to do color (or even texture) interpolation,
they usually requires huge amounts of memory.