1. A tetrahedralization filter of a three dimensional process/device simulation comprising: a receiver connectable to a data generator generating a non-conformal mixed-element mesh comprising elements subdividable into tetrahedra; a dynamic directory comprising a plurality of stored degree of freedom values for each subdividable element received from the data generator; a processor connected to the receiver and to the dynamic directory; and a three-dimensional process/device simulator, wherein an updated degree of freedom value replaces one of the plurality of stored degree of freedom values for a subdividable element neighboring an element being subdivided, and wherein the element subdivision is based on the degree of freedom values in the directory, with ordered subdivision beginning with subdivision of elements having a degree of freedom value lower than a predetermined degree of freedom threshold.