A two-dimensional "crystal" in direct space, and its reciprocal latticeP. Fraundorf, Bernard J. Feldman, W. Garver, M. Freeman, D. Proctor (2013) "Microwave Bragg-diffraction zone-axis-pattern analysis", arXiv:1307.7663 .. Note that the reciprocal-lattice or g-vectors (e.g. "a"* and "b"*) are parallel to the "d-spacing gaps", but not to the direct-lattice vectors (e.g. "a" and "b"). Also note the "shape transform" of the crystal convolving each of the "diffraction spots" in the panel at right. The pattern for this lattice in integer-pixel terms was simply "a" ∝ {2, -1, 0} & "b" ∝ {1, 4, 0}.