Optical wave data for a semiconductor device design is divided into regions (102). First wavefront engineering is performed on the wave data of each region, accounting for just the wave data of each region. The optical wave date of each region is normalized based on the first wavefront engineering (106). Second wavefront engineering is performed on the wave data of each region, based at least on the wave data of each region as normalized (108). The second wavefront engineering takes into account the wave data of each region and a guard band around each region including the wave data of the neighboring regions of each region. The second wavefront engineering can be sequentially performed in parallel by organizing the regions into groups (110).