All possible ratios between two notes from 2-tuplet to 8-tuplet feel. The green line represents a straight feel (1:1), and the vertical grey lines represent regular swing (1:2 and 2:1). The red lines represent the limits (1:∞ and ∞:1). The left side of the graph shows “short-long” swings while the right one shows “long-short” swings. The area between 1:2 and 2:1 represents the “soft swing” zone, outside of that is “hard swing”.
(Click to enlarge.)