public interface IPlottableBasic user-level interface to send generic graphic data to a plotter. It coworks with IPlottableRegion::plot(IPlottable). The IPlottable is a generic entry point to send graphical data to a plotter. The "type()" is intended for the plotting region to query the technology that is used in a received IPlottable. For example, someone can send an Inventor, java3D or HepREP scene graph to a plotting region. The plotting region, according to the concrete implementation of its graphic system, can accept or not the request. According the technology, the IPlottingRegion cast to a concrete Plottable object. It is the responsability of the concrete implementations (of a IPlottable and a IPlottingRegion) to establish a concrete protocol for passing graphical data. Note that someone can use the IGenericFactory system to create concrete IPlottables.