1. A computerized method of analyzing data for use in creating a mask that prints a desired pattern of features via a photolithographic process, comprising: obtaining data representative of a number of polygons that define a desired pattern of features to be printed via a photolithographic process; adding data representing one or more subresolution assist features (SRAFs) to the data that defines one or more of the printing features; fragmenting the data to define printing feature edge fragments and SRAF edge fragments; mapping one or more SRAF edge segments to a printing feature edge fragment; determining OPC corrections for the printing feature edge fragments to improve its edge placement error; and determining OPC corrections for one or more of the mapped SRAF edge segments to improve a second printing/imaging characteristic of the mapped printing feature edge fragment.