Currently processing 2.0 does not support beginRaw(), endRaw() and PGraphics3D has disappeared, that inspired me to look at alternative methods of exporting to PovRAY. I found that I could modify both toxiclibscore and hemesh libraries to export meshes from these libraries as PovRAY mesh2 objects. Here is an example of what I achieved with the hemesh library.
The beauty of this approach is that the export function is no longer dependent on the processing renderer (as was the case with my povwriter library) however it is a pity that I needed to customise the code to match each library. A major advantage of this method, is that the mesh2 format is well matched to the PovRAY internals, so that rendering is quicker and much better than as a union of triangles (as is the case with my povwriter library). The advantage of my original povwriter library (like dxf export) was that it could be applied to virtually any 3D sketch.
You can see my development process on my blog starting here.