Diffraction centered (red and blue)

Diffraction by a non-square array. The diffraction pattern shown is produced when the laser passes through the portion of the slide that is highlighted in red. What is the diffraction pattern of a rectangular array of dots? Of a parallelogram array of dots where the angle is not 90 degrees? Of a hexagonal array of dots? How are the orientations of the diffraction patterns related to the orientations of the arrays of dots? (Companion Experiment 4)