The povmesh library allows you to export toxiclibs mesh objects as PovRAY mesh2 objects. This is the preferred way of exporting mesh objects as the mesh2 object more closely matches the way vertices are handled in PovRAY. For other processing sketches there is used to be a povwriter library, which allowed instant preview (I might resurrect it yet).
Thanks to Dan Shiffman you can now download toxiclibs librarye from procerssing ide
You will for the foreseeable future have to build this library yourself, currently ant build but I will update to maven shortly.