The diameter of the sphere in the 3D-SNFG representation is exactly 4 Å, and the other shapes are scaled around the sphere. This size for the sphere was chosen based on the cross-section of a monosaccharide ring, which is approximately 4 Å in one direction and 6 Å in another. Although we tested shapes at sizes 5 and 6 Å, the over-sized shapes became crowded and ultimately failed to communicate connectivity information.