As Javi just pointed out, the names (create, cast) for the decorator functions are rather confusing since, for example, create is actually initializing the particle (and creating the decorator is just a side effect and there are many other ways to create a decorator).
I would propose that they change to Decorator::setup_particle for create since it sets up the required attributes on the particle and Decorator::decorator instead of cast, since it actually decorates the particle.
While these changes would touch a lot of code, they could be easily done, both in svn and your code via sed since "::create(" is probably always for a decorator in c++ (and ".create(" in python). I would check a shell script into tools to aid the update.
Comments? Better names?