1. A method of providing printability analysis for a defect on a physical mask, the method comprising: using a mask inspection system, generating a simulated wafer image of the physical mask; generating a simulated wafer image of a reference mask, the reference mask corresponding to a defect-free physical mask; identifying a first feature proximate to the defect on the simulated wafer image of the physical mask; identifying a second feature on the simulated wafer image of the reference mask, the second feature corresponding to the first feature; computing critical dimension deviations including the first and second features to provide the printability analysis; identifying a first plurality of features proximate to the defect on the simulated wafer image of the physical mask; identifying a second plurality of features on the simulated wafer image of the reference mask, the second plurality of features corresponding to the first plurality of features; and calculating a plurality of relative critical dimension deviations for the first and second plurality of features.